Tag Archives: registered design professional

What Size Posts Should I Use?

What Size Posts Does My Building Need and How Deep Should They Be?

Reader ANONYMOUS in BENTON writes:

“1. If my building has 16 posts and posts are 12 feet apart do I need 4×6’s or 6×6’s?
2. If the plan shows 16 feet above grade how much do I need underground?
3. If the posts are set 12 feet apart will two 2x12s glued together support a truss system with a total length of 36 feet?”

Mike the Pole Barn Guru responds:

While I appreciate your questions, we as a company and me as an individual do not provide free engineering services. In answer to your questions:

1) Without knowing the full dimensions of your building, including roof slope and overhangs (if any), if the columns will be adequately tied into a concrete floor, as well as your site’s snow load, design wind speed and exposure, seismic zone as well as the dead loads which will be carried by your building there is no possible way for me or any RDP (Registered Design Professional – engineer or architect) to be able to answer this.

2) The depth of the columns into the ground should be shown on your engineered building plans (you do mention you have plans). At a minimum the holes should be no less than 40″ deep and must extend below the frost line. Ultimately the depth and diameter will need to be determined by the RDP in consideration of the factors listed in (1) above, as well as designing for the ability to adequately prevent uplift.

3) Since I would use double trusses which bear directly upon the columns, there would be no need to use any other type of dimensional lumber to provide headers for a truss system. Again, this is where your RDP can design to adequately provide an engineered system to support the trusses.

My best advice, since I am guessing you are somewhat floundering in this, is to invest in a fully engineered post frame building kit package which includes plans sealed by a RDP and designed specifically for your building, at your site. It just isn’t worth trying to avoid the small expense into a proper design – especially when the lives of the occupants depend upon it.

Here are some other articles which pertain directly to this subject and should be read: http://www.hansenpolebuildings.com/2014/12/free-pole-barn-plans/ and http://www.hansenpolebuildings.com/2017/11/dont-engineering-fool/

 

 

 

 

Engineering Your Pole Building for Free

Please Let Me Engineer Your Post Frame Building For Free

Because I am not a Registered Design Professional, I can’t engineer your new post frame building for you. And, if I was, I most certainly would not be doing it for free. Typically an engineer should be compensated somewhere in the area of 8 to 12% of the value of the project, depending upon how involved they have to be with it, as well as if a visit (or visits) to the site are included.

Reader TERRY in FORT WAYNE had written and had his original request fly off into cyberspace, so he tried again:

“Mike, Thanks for getting back to me. That doesn’t surprise me!! Questions: 1) My barn will be 44’x32′ x15′ wall height with the trusses running the 44′ way. What size of holes do I need to bore for my post anchors? I’m not barring my post, pouring concrete to the top with 18″ tall “U” brackets made from 1/4″ plate and (4) jay hooks 18″ long on the bottom of brackets that will be in the concrete 18″s. Also what size header do I need on the truss support side if I install trusses every 24″ with plywood and shingles with A 16′ oh door opening .( Wanted to match my existing garage roof.) I will be tying the new barn to the existing garage on one end. If not a good idea what header to use with trusses at 8′ and wood purlin and metal roof? Let me know if you need any more info. Thanks for your help. Dirt is clay and figured at 3-4K in my area.

If you have any questions please call.

Thanks.”

Mike the Pole Barn Guru replies:
You are asking questions of me which should be directed to the RDP (Registered Design Professional – architect or engineer) who designed your building and provided the plans. These will include the foundation design as well as any truss carriers.

Some commentary – there are wet set brackets made specifically for post frame buildings. I would recommend you invest in them rather than trying to fabricate (or have fabricated) your own, unless they were designed by your RDP and inspected by him or her after production. For Clay soils, the Building Code allows a value of only 1500 psf – any greater values should be used only if an onsite soils test has been done by a registered engineer, else you are at risk of settling issues. See Table 1806.2 https://codes.iccsafe.org/public/document/IBC2015/chapter-18-soils-and-foundations.

If you are not too deep into your project and do not have an RDP involved, I would strongly encourage you to deal with a post frame building kit supplier who can provide engineer sealed plans and calculations for your building, along with the materials to assemble it and complete instructions.


 

 

Building Your Own Gambrel Barn Wood Roof Trusses

Gambrel style rooflines are often enticing, they offer the feeling (however not the reality) of getting added space for free. Building your own gambrel barn trusses might appear on the surface like a way to make this even a greater savings.

This was prompted by an inquiry from reader DON in WAYNE. Don writes:

“I am building a 24 ft. wide x 40 ft. length barn. I am going to build a gambrel truss with 2×8 and with 4 ft. wide gussets. How far apart should I space them using purlins and should I use 2×4 or 2×6 purlins. I was thinking of going 4’ wide with the trusses and using 2×4 spaced 2 ft. wide for the purlins.”

Mistake number one is even considering building your own trusses, on site, unless you are constructing them from drawings designed and sealed by a Registered Design Professional (RDP – licensed architect or engineer). Chances are way too good (100% guaranteed) you are dooming your building (and possibly its occupants) to failure. In all seriousness, prefabricated steel connector plated wood trusses are the only way to go – you will save money in the long run and you will be able to sleep soundly at night.

Your second mistake is in trying to be your own building engineer. If it was my own building (depending upon the design wind and snow loads), I would probably be using a single truss on each endwall and double (two ply) trusses every ten feet, bearing directly upon the columns. In my humble opinion this will give you the safest end resultant as the trusses can be notched into the columns and not possibly slide down the columns (or have a questionable connection to a header or truss carrier). You can then utilize 2×6 (or 2×8 depending upon loads) roof purlins on edge to support the roofing.

Your idea of using 2×4 (I am guessing flat over the tops of the trusses) every two feet and spanning four feet will not work unless you have the availability of lumber graded higher than the Standard and Construction material from your local lumber yard.

To avoid making crucial mistakes, which could waste your hard earned money, I would recommend you invest in a fully engineered post frame building kit package.

 

 

Hansen Pole Buildings is Number One

We Are Number One

 Hopefully you can survive the obnoxious YouTube commercial at the beginning: https://www.youtube.com/watch?v=04854XqcfCY.

Unlike the champions in Queen’s iconic 1977 hit “We Are The Champions”, Hansen Pole Buildings has merely won, from BUILD Magazine, their “Award for Outstanding Pole Barn Kits – USA” for 2018. It isn’t the world, however we like to believe we are the champions.

Whilet it is all fun to be recognized by the outside world, the true satisfaction comes from the kind words we receive from our clients, as well as the photos of their lovely workmanship. The pride of ownership of a project well done is overwhelming and we thank our clients for their unsurpassed kindness as well as the terrific photos.

About Hansen BuildingsHansen Pole Buildings does not rest upon our laurels, however. We are constantly working with RDPs (Registered Design Professionals – architects and engineers), as well as our valued vendors to develop new and better systems which deliver even greater value and long term successful performance to our clients. Our IT team is diligently adding to our Instant Pricing™ program to increase functionality, provide more custom and intricate options, as well as to decrease the window of time from order to delivery through automation.

It also is not as though we feel we alone are brilliant. The custom post frame building kit packages we provide are the result of hundreds of thousands of completed buildings, with input from D-I-Yers and builders all across the country.  Have a product, concept or idea which might make us and our buildings better? Don’t be shy about sharing – we love hearing from you!

In the meantime, please continue (or begin for the newcomers) enjoying reading both these blog articles as well as Monday’s “Ask the Pole Barn Guru” column, as I strive to entertain and inform.

Every member of the Hansen Pole Buildings’ team strives for one thing – to deliver “The Ultimate Post Frame Building Experience”™!

 

How Not to do a Post Frame Sheer Wall

How Not to Do a Post Frame Shear Wall

Reader DAVID in MIDDLETON writes:

“Hi we are currently building a 40/72 pole barn. We are wrapping the bottom 4 feet in OSB for sheer strength along with sheeting the roof with osb. We want to insulate the walls and put a drop ceiling in the pole barn to fully insulate it later this year. What do we need to do now for ventilation while we are building it to make sure we don’t have condensation issues later.”

Whilst friend David is writing about one issue, he is throwing out a bone as to why self-engineered post frame buildings are not always the best route to go. David is well intentioned, however his design solution would result in added expense without added benefits.

Always (may I repeat Always) construct only post frame (pole) buildings which are designed by a RDP (Registered Design Professional – engineer or architect) specifically for your building upon your site. You will always get piece of mind and usually the RDP will save you more money than what you invested for their design work.  

Here is my response to David:

Before we get to discussing your question, a few words about your design.

Wrapping the bottom four feet in OSB is going to do little or nothing to improve wind sheer resistance. In order to be effective as a sheer wall, the OSB needs to run from the splash board up to either the eave girt on the sidewall or the bottom chord of the truss on the endwall. All panel edges need to be blocked with 2x material. The shear panels should be no less than a 1:4 ratio (one foot of shear panel width per four feet of height) and ideally 1:2. On the roof, make sure to use at least 30# felt between the OSB and steel roofing and locate the roof screws so as they go into the underlying purlins, not merely into OSB.

Back to the question at hand…..

Your building should have vented soffits, of at least 18 inches in width to provide an adequate air intake. Trusses should be fabricated with raised heels – ideally two inches higher than the thickness of the attic insulation. Take care not to block the airflow from the soffit with the attic insulation. Vent the ridge.

Pour the slab on grade only over a well sealed vapor barrier, otherwise excess moisture will enter the building from the ground beneath the building. Also, the slab will need to be sealed – not as good as the vapor barrier route, but it is better than doing nothing.

Completely fill the wall cavity with insulation. Unfaced batt insulation can be used, however BIBs will be a fair superior design solution. Read more about BIBs here: http://www.hansenpolebuildings.com/2011/11/bibs/.

Either choice of wall insulation requires a clear visqueen vapor barrier on the inside. Make certain to seal any seams, rips or tears. There should not be a vapor barrier between the ceiling framing and ceiling materials.

 

 

18 Foot Span Roof Purlins?

The Possibility of 18 Foot Span Roof Purlins?

Reader CHRIS writes:
“I have a building I want to build but I am not able to add the height I need on the side walls.  My plans are 24 deep by 30 wide with 8 foot walls.  Roof trusses would be 24 ft.  My problem comes from overhead power lines.  They are right in my way.  I really need 10 or more feet of ceiling.  The wall structure will be 2×4 residential style build with double top and bottom boards this should spread the weight out on the concrete well.

The span of the 1st section (north side), would need to be 18ft.   If I used a triple truss at 18 ft. and 2×8 purlins would I be able to get this to work.  I will be using a metal roof the 30 ft. wall will have a 16 ft. door and 9 ft. door Eve entry.  I know it’s not optimal.  But to get a lift inside the garage it will be a must to get this span.  Also my garage door will follow the roof line. In the 18 ft. area it will be hung from the purlins.  A winch will be used as an opener.  Also attached to the purlins but boxed to prevent movement.”

Mike the Pole Barn Guru writes:
In most jurisdictions you are not allowed to build under power lines – you need to be consulting with your local power company and your Building Official first. Even if it is allowed, you would be wise to have the lines relocated, or buried so as to not have a future issue. A live wire comes down on your nice new steel roof and poof!

Depending upon your roof load and wind load, it might be possible to span 18 feet between trusses with purlins, however they are probably going to need to be larger than 2×8. With the proper truss design, it might very well be able to carry the end of the purlins with a double truss.

What you are proposing is well outside of the prescriptive portions of the Building Codes, so whether stick framed or post frame (post frame will be far more economical) you should be utilizing the services of a RDP (Registered Design Professional – architect or engineer) in order to make sure you have a new building which is adequately designed to support the imposed loads.

Indiana Class 1 Building Must Have Posts on 4′ Centers?

Indiana Class 1 Building Must Have Posts on 4’ Centers?

Reader GARY in CONNERSVILLE writes: “I am going to build a 60 x 160 , 18′ ceiling height for a sawing operation at our plant. I am told being a class 1 building, employee occupied, that the side posts need to be on 4′ centers, however the architect says otherwise. Can you shed some light on this? Thanks”

Best place to start is with the Indiana Code definition of a Class 1 structure:

IC 22-12-1-4

“Class 1 structure”

Sec. 4. (a) “Class 1 structure” means any part of the following:

(1) A building or structure that is intended to be or is occupied or otherwise used in any part by any of the following:

(A) The public.

(B) Three (3) or more tenants.

(C) One (1) or more persons who act as the employees of another.

(2) A site improvement affecting access by persons with physical disabilities to a building or structure described in subdivision (1).

(3) Outdoor event equipment.

(4) Any class of buildings or structures that the commission determines by rules to affect a building or structure described in subdivision (1), except buildings or structures described in subsections (c) through (f).

(b) Subsection (a)(1) includes a structure that contains three (3) or more condominium units (as defined in IC 32-25-2-9) or other units that: (1) are intended to be or are used or leased by the owner of the unit; and (2) are not completely separated from each other by an unimproved space.

(c) Subsection (a)(1) does not include a building or structure that: (1) is intended to be or is used only for an agricultural purpose on the land where it is located; and (2) is not used for retail trade or is a stand used for retail sales of farm produce for eight (8) or less consecutive months in a calendar year.

(d) Subsection (a)(1) does not include a Class 2 structure.

(e) Subsection (a)(1) does not include a vehicular bridge.

(f) Subsection (a)(1) does not include a structure that is intended to be or is occupied solely to provide periodic maintenance or repair of: (1) the structure; or (2) mechanical or electrical equipment located within and affixed to the structure. As added by P.L.245-1987, SEC.1. Amended by P.L.223-1989, SEC.1; P.L.23-1993, SEC.149; P.L.2-2002, SEC.72; P.L.141-2003, SEC.2; P.L.92-2012, SEC.2; P.L.142-2013, SEC.2.

With the definition of an Indiana Class 1 building in hand, I went on a search to see if I could verify the, “I am told”. I don’t know who is telling you sidewall columns must be placed every four feet, as I cannot find a shred of evidence to back the statement up. In the case of Hansen Pole Buildings, we have provided numerous Class 1 post frame buildings across the state of Indiana, none of which had columns every four feet – in fact I know of at least one which had sidewall columns every 14 feet!

My vote is you are smart in having the involvement of a Registered Design Professional (RDP – architect or engineer) who is capable of wading through the mire and muck to weed out the supposition from the reality. The IBC (International Building Code) is not a prescriptive Code, it allows qualified designers to use sound engineering practice to design post frame buildings which will last a lifetime or more.

Top Plate

Top Plate (Truss Carrier) Size With Attic Trusses
Question from reader JEFFREY in STAPLETON:
“I’m building a gambrel pole barn 30ft x 50ft , these are attic trusses with a 16ft room sitting @ 2ft oc, will 10ft pole spacing with double 2×12 top plate be sufficient, any suggestions?”

 

Mike the Pole Barn responds:
My first suggestion is to invest in a fully engineered post frame building kit package. Again – “fully engineered” being the key phrase – this means the building is designed specifically for you, on your site, with your features (doors, windows, other openings, etc.). Engineered trusses do not make for an engineered building!

Suggestion number two: If you, for some unknown reason, feel a fully engineered post frame building kit package happens to not be for you (usually this happens when clients have the misguided thought they can buy materials at retail prices for less than the building suppliers can at wholesale) at the very least invest in the services of a Registered Design Professional (RDP – architect or engineer) who is capable of performing the proper design calculations to provide plans which will result in a structurally sound building.

As to your particular scenario, provided your building has no overhangs – those two 2×12 (provided they were #2 Douglas Fir – the strongest of the four most common framing lumber species) would only be able to carry somewhere around 25 pounds per square foot of load. This would be barely enough to carry the required roof load plus the weight of the trusses, to say nothing of the attic bonus room you intend to add.

A design solution might be to place a pair of attic trusses directly aligned with the sidewall columns. This would provide direct bearing from the truss to the column and would eliminate the need for truss carriers (aka a top plate). This would be a far more reliable system, as the true double trusses load share and reduce the possible incidence of a weak link in a single truss taking down the entire roof system.

The widely spaced trusses also allow greater freedom in locating stairs for access – trusses every two feet do not provide for an adequate space to get a three foot width stairs between the trusses.

Don’t Hire a Contractor Unless You Are Willing to Take a Risk

From The Dalles (Oregon) Chronicle December 26, 2017: “A theft report was filed Wednesday morning concerning a theft by deception when a woman reported she paid a contractor $30,000 to build a pole barn on her property by the end of October and no work has been completed.”
Most people assume when they hire a contractor to erect some or all of their new post frame (pole) building or pole barn, they are minimizing their risks.

Let’s define exactly what risk is:
Risk (according to the sum of all human knowledge Wikipedia) is the potential of gaining or losing something of value. Values (such as physical health, social status, emotional well-being, or financial wealth) can be gained or lost when taking risk resulting from a given action or inaction, foreseen or unforeseen (planned or not planned). Risk can also be defined as the intentional interaction with uncertainty.  Uncertainty is a potential, unpredictable, and uncontrollable outcome; risk is a consequence of action taken in spite of uncertainty.
Risk perception is the subjective judgment people make about the severity and probability of a risk, and may vary person to person. Any human endeavor carries some risk, but some are much riskier than others.

Now, gentle reader, please pay attention to, “risk perception is the subjective judgment”. Subjective judgments are made without clear analysis of objective facts.

Hiring a contractor is a game of chance, there is risk involved. Significant risk.

Numerous possible outcomes are the resultant of hiring a contractor. The ideal outcome is everything went perfect – the project was completed satisfactorily, the building successfully passed all Building Department inspections, it was built according to the engineer sealed plans, there were not cost over runs and it was built in a timely manner.

Back in the day (the 1990’s) I participated in a contract writing class for building contractors put on by the WBMA (Western Building Materials Association). The course was taught by an attorney. The attorney prefaced the discussions by saying if we (the contractors) had over 50% of our clients satisfied with our work, we are doing extremely well.

Let this sink in – 50% satisfaction as a benchmark for success as a building contractor?
So, what happens if the outcome is less than ideal?
The worst case is paying for a building and getting nothing.
Other less than fun outcomes include (in no particular order); Some or all of the building is completed and mechanics liens get filed on your property due to the contractor not paying his or her suppliers or the help. The building won’t pass inspection and/or was not built to the engineered specifications. The building has warranty issues the contractor will not or cannot fix. The building gets partially built and contractor absconds with more money than earned. The building collapses – killing you or a loved one.

Scared yet?
YOU SHOULD BE!

How to minimize risk:
Demand your building be constructed according to plans prepared by an RDP (Registered Design Professional – architect or engineer).

Invest in a complete building kit package per those plans, it avoids potential material liens and you can control the design.

Vet potential contractors fully, by following these steps: http://www.hansenpolebuildings.com/2013/07/contractor-6/.

Require a Performance Bond from the contractor you select: http://www.hansenpolebuildings.com/2012/07/contractor-bonding/.

How big a risk are you willing to take?

My Response: Why We Need Building Codes

My Response: Why We Need Building Codes

As promised, here is my response to the Coeur d’Alene Press article of December 5, 2017 (exactly as I wrote in the comments portion following the newspaper article regarding adoption of building codes):

I will first qualify myself – I attended the University of Idaho in architecture. I was a manager or owner in the prefabricated wood truss business for over 20 years. I’ve been a registered general contractor in four states, In 1987 I joined ICBO (they write the Codes) as well as ASAE (American Society of Agricultural Engineers) and was a sitting member on the committees which established the huge majority of the structural design criteria for post frame (pole) buildings. I have had the privilege of being involved in the structural design of nearly 20,000 buildings in every U.S. state. I am a contributing writer for Rural Builder magazine.

In my humble opinion – anyone who wants to “run bare” without Building Code minimum standards being applied to their new structures is out of their freaking mind.

The Building Codes are designed specifically to protect the safety and lives of those who occupy (or are in the vicinity of) structures. The Code requirements are ‘minimum’ standards, which are just scraping by – however something is better than nothing. For residential occupancies, the risk (under Code) is a once in every 50 year probability of the design loads for a given home to be exceeded! And yet there are some who would do away with even this minimal amount of protection.

I am not at all an advocate of governmental intervention, however only a fool acts as their own engineer. I deal, on a daily basis, with challenges posed from new building owners who have had under designed buildings constructed in jurisdictions which do not require structural plan reviews.

Mr. Tyler’s concern about homes having been built on unstable ground is not the fault of the Code, but the fault of the agencies which issued the permits. A geotechnical study should be done for the proposed site of any new structure – this allows the RDP (Registered Design Professional – architect or engineer) who designs the structure to have adequate information to be able to properly address foundation challenges, before they become foundation issues. The Code does not mandate engineered soils reports.

As to length of warranty provided by builders – an educated new building owner will look for a builder who offers an extended warranty. This, again, is not a function of the Code.

Having accurate information about snow loads is crucial to proper structural design. The 2015 edition of Ground Snow Loads for Idaho was produced by the Department of Civil Engineering at the University of Idaho. Based upon 31 more years of snowfall study than the previously used document – it appears Ground Snow Loads in Kootenai County should range from 43 to 100 psf (pounds per square foot) depending upon one’s location within the county.

Several factors go into calculation of Ps (sloped roof snow load) from Pg (ground snow load) including exposure to wind, is structure heated or not, importance of building, slope of roof and roofing material. In many instances the calculated Ps load is going to be higher than the currently accepted 40 psf. Will this add to construction costs? Yes. Will it help prevent failures and possible loss of life? Yes.

What is the value of even a single life?

Rather than throwing the baby out with the bath water, my advice is to require every single building to be designed per current Code to include plans which are sealed by a Registered Design Professional.

 

Put the Architect in Charge?

Put the Architect in Charge?
I spent several years paying off my college student loans from Architecture school, so I do have a profound respect for architects who have been able to make a living practicing their trade. This, however, does not mean I feel the intervention of an architect is appropriate in all situations and circumstances.
Case in point, from a copyrighted article in the Greenfield, MA “The Recorder” of November 29, 2017:
“BUCKLAND — Accepting the recommendations of the Highway Garage Building Committee, the Selectboard is asking Wilbraham, Vt., architect Roy S. Brown for a price proposal on the design and cost estimates for building a 5,000-square-foot town highway garage and a 5,000-square-foot pole barn to store equipment.
The town bought the 4.7-acre former Mayhew Steel property in March 2016, but needs a municipal garage that meets state building code. The plan includes demolishing most of the old Mayhew Steel complex.”
There is a strong possibility Hansen Pole Buildings could have saved the 1902 residents of Buckland, MA some of their tax dollars. At absolutely no charge to municipalities and governmental agencies which are looking at new structures which could or should be post frame buildings, we will provide both a free cost estimate, as well as engineer sealed plans and specifications which can be utilized when sending the project out for bid.
Why?
We happen to be taxpayers as well and we care deeply about the squandering of our contributions on government projects. If we can help to hold down the costs and provide for the public true value for their investment, we sleep well at night.
Do you know of a town, city, state or even federal need for a new building? If so, let us know whom to contact.
For more reading on this subject: http://www.hansenpolebuildings.com/2016/11/free-engineered-pole-building-plans/.

Pole Barn Footings

Some things in life amaze me – magicians are one of them. I have no idea how the do what they do, but I am totally fascinated by them (you can read about my college experience with a magician here: http://www.hansenpolebuildings.com/2014/08/lumber-bending/). One of the other things which amaze me are how clients will invest tens (or hundreds) of thousands of dollars on a new post frame building, only to cheap out on the footings!

Anything of high quality requires a good foundation.  In post frame buildings, the measure of a good foundation’s investment is small in comparison to the overall picture.

Reader CHRISTINE from SPOKANE writes:

“We see all these posts about footings. It seems here they just pour concrete around post with no footings. Is that due to the nature of our rocky soil. Our posts are in the ground, no footing and ready for concrete, architect plans, say “bottom of all footings to bear on undisturbed ,native, inorganic soil 1′ min below grade. Extend all footings 4′ min below finish grade.” Did I assume wrong and he’s calling for an actual footing? TYIA! ASAP”

Dear Christine;

For years we designed our post frame buildings without a concrete footing below the columns, instead relying upon the concrete encasement around the posts to adequately bond to the pressure preservative treated column. The bond strength between concrete and wood is documented and more can be read about it here: http://www.hansenpolebuildings.com/2013/04/pole-barn-post-in-concrete/. There were some Plans Examiners who did not look kindly upon this as a design solution.

The Building Codes do specify the requirement for a concrete footing, and as such we moved several years ago to a design which placed eight inches thick of concrete below the column.

As an architect designed your building and placed his seal upon the plans, you are obligated to construct the building per his/her solution. There should be a detail on the plans which shows exactly what the architect had in mind. If there is not, request a clarification as this is something you paid for in your fee for the work.

Mike the Pole Barn Guru

Looking for a post frame building with a column embedment design which both makes sense and works structurally? If so, only consider a building which comes with plans done specifically for your building, on your site, and sealed by a Registered Professional Engineer.

Overhead Door Columns in Pole Barn Enclosure

No Columns for Overhead Doors

There are a few clients out there who leave parts of one or more walls open, with the idea of enclosing them at a later date. Most often this is done with the idea of being able to save money, however it is not always much of a money saver, especially if done wrong.

Here is just one example of why fully enclosed is a bargain compared to three sided: http://www.hansenpolebuildings.com/2014/03/three-sided-building/.

Reader NATHAN from MOUNT VERNON writes:

“I have an existing pole building that is 36 by 36 (12′ spacing on all columns) and is 16′ at the front, 20 at the next column back, 16 again at the second column and 12 at the rear of the structure. It is only sided on two sides (back 12′ wall and one side). I’m looking at finishing the building out with three 14ft doors on the front, but no columns were installed for this purpose. The concrete poured for the existing columns will prevent me from having proper footing if I put in new columns as in a new build. Can I bolt the new columns to the existing ones (Blocking and 5/8’s galvanized threaded rod) and have the bottom in a post base of suitable size and strength. As there is no concrete floor in the structure at this point I was also thinking of increasing the slap thickness in these areas and adding rebar. Your help is greatly appreciated Nathan.”

Nathan happens to be in a part of the country which requires Building Permits for most everything. At some point in time he is going to have to have a Registered Design Professional involved (RDP – architect or engineer) as his Building Official is going to want to see an engineer’s seal on the plans for the remodel.

There are numerous possibilities the RDP may take for a design solution. To keep in mind, these columns will be supporting no roof load, so it is merely a case of having them be adequate in size to resist wind loads, as well as the door itself.

While Nathan’s idea probably works, it might be easiest to mount the columns needed for the overhead doors into appropriately designed column brackets: http://www.hansenpolebuildings.com/2012/01/concrete-brackets/. A header can be run from one roof supporting column to the next to stabilize the top of the columns.

Before getting into a situation such as Nathan’s, research all of the options available. You might be able to enclose the building fully for little or no extra investment. As another alternative, financing is available which (with moderately reasonable credit) could allow some or all of your new building to be funded from a third party source with affordable monthly payments.

Check into your financing options today: http://www.hansenpolebuildings.com/financing/

 

What Type of Barns Do You Sell?

And my response to the question would be, “What type of barn would you like to invest in”?

Here is the full question asked by JOEL in THOMASVILLE:

About Hansen Buildings“What type of pole barns do you sell? (Truss on post or truss on band)
Also what’s the spacing on the trusses? 2 foot, 4 foot”

 

 

 

I will preface my answer with this sage (since I am nearly 60) advice – focus on the design solution, not on how the design solution is arrived at. Please feel free to reread the bolded words repeatedly, as this is the clue to getting the most post frame building for your investment.

Exactly what is the design solution?

The design solution is what meets your needs for functionality. It doesn’t much matter if your new building is free, how the trusses connect, or what their spacing is, if the building does not meet with your needs.

This is where “The Ultimate Post Frame Experience™” comes into play. Let the experts help to guide you towards a new building which will perform admirably for you, your descendants and future owners of your building for years. Simple things such as getting the right sized doors for the building and spacing them properly to avoid damage to vehicles and equipment; getting a height adequate for your needs if you plan upon multiple stories or need headroom for a vehicle lift.

The design solution is the “sizzle”.

Back to the question at hand……

The most important answer is no matter how it is put together structurally ONLY invest in a building where the plans exactly meet with what you are building and a wet sealed by a RDP (Registered Design Professional  – architect or engineer). If a highly trained professional with years of schooling and internship hasn’t done the structural design, then who did?

If I had my personal druthers, I would most typically recommend a building with widely spaced sidewall columns – most often 10 to 14 feet on center.

But isn’t this a long distance?

In the global scope of life – no.

What this DOES do is it minimizes the number of holes which need to be dug (digging holes is the least fun part of the job). It also allows for much easier addition of a sidewall door – think about it, if posts are say eight foot on center, it doesn’t allow for even an eight foot width overhead door (which eats SUV mirrors anyhow) to be added without cutting a column off!

In most cases, widely spaced columns, which directly support ganged (two or more) trusses connected face-to-face, is going to provide the greatest structural integrity, fewest individual parts to handle and be easiest and quickest to construct.
The Hansen Pole Buildings’ Instant Pricing™ program, does allow for all structural options to be checked – it will do single or double trusses directly bearing upon columns, or trusses paced upon truss carriers (truss on band) at either two or four foot on center. As the new post frame building owner – go for the design solution and allow the “how” to the experts!

ASCE Changes in 2017

ASCE/SEI 7 Minimum Design Loads for Buildings and Other Structures

The times, they keep a changing, and as they do Building Codes and Building Design becomes increasingly more complex. My long time readers have read my preaching about why all buildings should be designed by Registered Design Professionals (RDP – architects or engineers) to insure new construction meets with the requirements and provisions of the Code.

The 2016 edition of ASCE Minimum Design Loads and Associated Criteria for Buildings and Other Structures will be available in early 2017. This edition provides the most up-to-date and coordinated loading standard for structural design. Also with improved coordination and routine updates, ASCE 7-16 includes many significant changes.

New seismic maps reflect the updated National Seismic Hazard Maps, including requirements for the region surrounding Las Vegas, Nevada, to address local concerns. The basis for the increase was developed and supported by the State of Nevada Geologist’s office.

New wind speed maps which result in reduced wind speeds for much of the country and clarify the special wind study zones, including new maps for Hawaii. Also new maps for Risk Category IV separate from Category III.

In my humble opinion, the wind speeds expressed in ASCE 7-10 were at times unrealistically high in comparison to actual historical measures. This resulted, in some cases, in added expense to new building owners – which they were not given a choice in accepting or declining.

New regional snow data generated by state Structural Engineers Associations in Colorado, Oregon, New Hampshire, Washington and other mountainous states, which is now directly referenced and eliminates many, older site-specific Case Study zones.

New provisions for performance fire design.

An entirely new chapter with tsunami design provisions, which is important to west coast states, Alaska and Hawaii.

Full coordination with referenced material standards within ASCE 7-16, to ensure they are the same as those which will be referenced by the upcoming 2018 International Codes.

Consistent with revisions to all editions of the ASCE 7 standard, some of the revisions will cause increases and some will cause decreases in the cost of construction for an overall project. In fact, the variability of the impacts on construction resulting from different hazards may be compounding or may negate the effects. The cost impact for each significant change to ASCE 7-16 has been considered.

Please keep in mind, all versions of ASCE 7 and the International Building Codes are establishing minimum requirements for structural design. It is this author’s recommendation to always err on the side of caution when selecting criteria for climactic loading. Often increases can be made in design loadings with little or no cost to the overall building project. Those contemplating a new post frame building are best to inquire as to the extra investment (if any) to design for greater loads.

When Buildings Fall Down

When Buildings Fall Down, People Can Die

Building PermitIt was a busy Friday morning in downtown Sioux Falls, South Dakota on December 2nd of this year. About 10:30 a.m. near the corner of East 10th Street and South Phillips Avenue, Boyd McPeek was inside the Coffea coffee shop, when the 1916 building across the street collapsed.

“I just happened to glance out the window and I saw the front door fall out and a cloud of dust,” McPeek said. According to McPeek, the collapse left the people in the coffee shop speechless. “It was kind of slow motion as the bricks were falling,” McPeek said.

Joe Batcheller, Executive Director of Downtown Sioux Falls, speculated the construction work weakened the nearly 100-year-old building, causing the collapse.

Sioux Falls City Building Services approved a limited building permit authorizing Hultgren Construction to remove interior finishes, such as furnishings, floor coverings, ceiling tiles, and an existing bar area. The city was awaiting structural engineering and architectural submittals from the builder before issuing authorization to begin any further work on the project, according to city officials.

Now, please keep in mind, the city had not authorized any structural changes, yet the contractor posted on their Facebook page, two days prior to the collapse, a photo showing a structural wall having been removed.

The building collapse resulted in the unfortunate (and probably avoidable) death of a workman who was inside the building at the time.

How does the collapse of a century old building impact your choice of whom should provide your new pole building?

The key phrase is the city was awaiting “structural engineering and architectural submittals”….. unless you personally happen to be a Registered Design Professional (RDP – engineer or architect), it truly is not prudent to design your own pole building. Nor should you entrust your life, or the lives of your friends or loved ones, to a building which has not been designed by a RDP.

If an engineer didn’t design it – then who did?

Do it Best

Do it Best®

I get a lot of people asking some great questions of the Pole Barn Guru. Some of which take some lengthy answers, in order to adequately make the point. Here is one which involves the thought of doing business through a Do it Best® store would add a level of security.

For your reading pleasure……

DEAR POLE BARN GURU: I have shopped for a pole barn for several months. I wanted a simple 30x40x10. I got several quotes and put a lot of thought into the project. I was concerned about “fly by night” builders. I wound up choosing a “doitbest” retailer, hoping that they would have the backing in case something went awry. The builder arrived yesterday to begin construction, I had to leave for work but my Dad came over to oversee the project. He noticed that when they set the poles, they did not use any concrete below or around them. The builder just backfilled the holes. My question is this; Is this an acceptable practice? They have not put the sheet metal on yet, should I stop the process until we discuss this? I am not an engineer or contractor, but it doesn’t seem like a good idea to have no concrete around or under the posts. Please advise? CHRIS IN CARTHAGE

DEAR CHRIS: If you shopped for several months and got several quotes, it sounds like you did put a fair amount of thought into your new pole barn (post frame building).

Do it Best® bills itself as the “World’s Largest Hardware Store”®. It is a cooperative which is owned by its approximately 3800 members, making it the only US-based full-line, full-service, member-owned distributor of lumber, hardware, and building materials products in the home improvement industry. Each store is independently owned, so dealing with a Do it Best® location gives you only what little protection can be afforded by the store you did business with. It is not like The Home Depot® or Lowes®, where every location is corporately owned and you are afforded the protection of a multi-billion dollar chain.

Regardless of the builders affiliation or lack thereof, it is important to do due diligence in thoroughly vetting them out. I’ve shared this many times in my articles, but apparently it has been under utilized: http://www.hansenpolebuildings.com/2013/07/contractor-6/

drilling-hole-150x150On to your question. Placing no concrete under or around the building columns is probably a recipe for disaster – no building of any sort is going to prove to be better than its foundation. Although it is possible to engineer a foundation without concrete, it would involve enough extra efforts (and usually some very deep holes) in order to make it work. The concrete in the holes serves numerous functions – it has to be able to adequately distribute the weight of the building and any imposed vertical loads (like snow and ice) into the soils beneath the building to keep it from settling. This is a prevalent problem with most post frame (pole) buildings, where either no concrete or an inadequate amount of concrete has been placed below the columns. Building codes require a minimum of a six inch thick footing. Having the concrete up the sides of the column, above the footing aids in prevention of uplift (your building being sucked away) as well as overturning, neither of which would be a pleasant experience.

Here is a recent instance of a new pole building owner with a similar experience to yours: http://www.hansenpolebuildings.com/2016/08/pole-barn-columns-settle/

In my humble opinion – you should stop the builder immediately and demand he provide an engineer’s certification of the adequacy of what he has done for a footing/backfill. He is not going to be able to do it, so the next step is to have him provide an engineered repair (which means it is wet sealed and signed by an engineer) and then make sure he actually does the work prescribed by the engineer.

I am going to guess the building which you have invested in is not an engineered building – where the plans have the “wet seal” and original signature of a RDP (Registered Design Professional – engineer or architect). This affords a new building owner the assurance someone who actually has the knowledge of structural design has verified the adequacy of the overall building design as well as the strength and load carrying capabilities of every member and connection. I also cannot imagine your building is somewhere structural building permits and site inspections occur – if it is, then get your local Building Official involved, as it is his or her responsibility to look out for the safety of those who are investing in new construction.

Good luck, and let me know how it turns out!

Will 4×6 Columns Carry the Load?

Another excellent question from a soon to be new post frame (pole building) owner.

Post-Holes-150x150DEAR POLE BARN GURU: The materials just arrived for my pole barn and construction is to start on Monday. The building will be 30×40 with attic trusses with an 8/12 pitch, 24 inches on center with a 1ft overhang (there is a total of 21 trusses). In the materials there was 4- 28ft 6x6s, and 14-18ft 4x6s. My question is will the 4×6’s be able to handle the load bearing of the attic trusses, or should they be 6×6’s as well? Thank you for your help. JIMMY IN PLYMOUTH

 DEAR JIMMY: I tried to look you up in our data base, but found you are not one of our clients, however, I am always happy to help anyone who takes the time to ask a question. At Hansen Pole Buildings, every member (columns and boards) in the building is checked via a sophisticated and proprietary software system to insure all components and connections are properly designed to support the loads which will be applied to them – prior to going to the engineer who reviews all of the work and verifies it is correct. Only then are your components ordered and scheduled for delivery.

With 18 foot long columns, I would surmise you have a 14 foot eave height. Not knowing all of your load conditions (roof and ground snow load, design wind speed and wind exposure) I can only rely upon judicious experience when I say it would be highly unlikely a 4×6 column would be adequate to carry the loads.

In many cases a 4×6 is stronger than a 6×6 (here is why: http://www.hansenpolebuildings.com/2014/08/lumber-bending/). The one place where the 4×6 falls down (hopefully not literally) is as the columns get longer from grade to truss, the 4×6 tends to want to buckle in the narrow direction.

My recommendation – ask your contractor (or the supplier of the pole barn kit package) to show you the engineer sealed plans for your building. This is your only assurance the structure will be adequately designed to withstand wind and snow loads. If they cannot provide the engineering, for whatever reason, I recommend you delay construction until an engineered design is provided. Keep in mind also, an engineer sealed roof truss drawings is NOT the engineering for your entire structure (far too many folks believe if the trusses are engineered, the building is as well).

Best of luck to you, and if you do not mind, please share the results of your questioning.

To my loyal readers – my educated guess is Jimmy is going to find out the building he has ordered was not designed by an engineer and the columns as delivered are under designed. I would encourage anyone who is going to invest their hard earned dollars into a new post frame building to demand it be designed specifically for your needs (not something which is generic and maybe close) by a Registered Design Profession (RDP – architect or engineer).

Here is a secret I have shared before:

http://www.hansenpolebuildings.com/2014/10/non-engineered-building/

Prefabricated Roof Trusses Part One

Prefabricated Roof Trusses – They can Make You or Break You

This article (written by yours truly) was published in the May 2016 Rural Builder magazine (http://media2.fwpublications.com.s3.amazonaws.com/CNM/RB_20160501e.pdf and begins on Page 26). Although the article is written towards post frame (pole) building contractors, it gives a perspective as to the challenges of ordering something as apparently simple as a set of prefabricated roof trusses:

I worked for, managed or owned roof truss manufacturing facilities from 1977 until 1999 – so we only ever had to operate under the pre-International Building Codes, which made our lives easy. Regardless of roof slope, exposure to wind, roofing material, whether a building was heated or unheated, the top chord live load (or roof snow load) was the same within any localized geographic region, with the exception of differences in snow load caused primarily by elevation changes.

When a client brought in a set of plans, we took on the responsibility to insure the quantity of trusses, roof and ceiling profiles, etc., were correct. We looked upon ourselves as being the experts – rather than the builder or building owner who was purchasing the trusses.

Walk in the door of a truss company today with a set of plans for a truss quote and the expectation is the purchaser has to be “in the know”, which I personally find counter intuitive, but it is the current reality.

As a broad generalization, today’s truss manufacturers are looking out for one entity, and it is not the person writing the check to pay for their product.

I am going to share some secrets which should both increase your bottom line as well as allow you to sleep soundly at night.

First – do not assume the truss company is going to do it right. It is better to take the more realistic position of, they will do it wrong. Wrong can result in an increase in the probability of a catastrophic failure, having to pay more than one should, or both.

Secondly – if you are shopping various vendors, the best price on the truss order might not be the best buy for your building.

A little sharing into how to make sure the trusses you order actually meet the required load conditions.

I am going to put in a plug here for Registered Design Professionals or RDPs. If you are constructing post frame buildings, or providing post frame building kit packages, and are not using originally RDP sealed plans, which are specific to the address where the building is being erected, you are seeing the light at the end of the tunnel and the light is a speeding train.

Maybe you have built or provided hundreds or even thousands of buildings and never had a failure. Trust me, the failure is going to come, and may have nothing to do with how the building was designed, but if an RDP did not design it you are placing yourself and your business at a tremendous risk.

On to important stuff, the Building Codes.

The IRC (International Residential Code) is a prescriptive code for stick frame buildings within limited parameters of snow and wind loads. It does not address post frame construction therefore all post frame buildings should be designed using the IBC (International Building Code).

The International Building Code (IBC) identifies the appropriate Ground Snow Load (Pg) to use on a building based upon its location. When jurisdictions adopt the IBC, they should also be designating the Pg value or values within their area of coverage. Some Building Officials are still rooted in the 1900’s and (contrary to the current Code) designate a Roof Snow Load, which often defies the Laws of Physics.

A case in point, not too many years ago, we provided the post frame building kit package for the Nature Center at the Cheyenne Mountain Zoo in Colorado Springs, Colorado. The Building Department gave the ground snow load as 27 psf (pounds per square foot), yet wanted 40 psf as the roof snow load. When our engineer called the Building Department to discuss this, the explanation given was, “The snow is just different here!”

Hmmm, ‘the snow is just different here’. Sounds pretty scientific. How about I give you some guidance as to what to really pay attention to, so your building is not only designed correctly to stay up but also how to save you some money. Sound good? Well, come back tomorrow to read Part II and get those answers… and a whole lot more.

Requirements by Building Departments

The Road to Hell is Paved with Good Intentions

Around about 1150 Saint Bernard of Clairvaux is thought to have originated the phrase. It is highly unlikely he had the prescriptive requirements provided by Building Departments for post frame (pole building) construction in mind at the time.

More powerful people than I have ranked and railed against prescriptive requirements for pole buildings. Here is my rant on the subject: http://www.hansenpolebuildings.com/2012/02/prescriptive-requirements/

The tremendous majority of Building Departments truly want to help good folks out. In the rush to use those good intentions information gets spread to the public, which in the wrong set of circumstances could prove to be dangerous, if not deadly.

Most often I have seen pole barn “handouts” from smaller Building Departments. This left me totally aghast when one of our clients shared with us this link: http://www.cbs.state.or.us/bcd/programs/ready_build_plans/2014/pole_bldg_2014-01_24X36.pdf

Here the Building Codes Division is providing a “Ready Build Plan” for a 24’ by 36’ post frame building with an eave height up to 14 feet. The plans are based upon the 2010 OSSC (Oregon Structural Specialty Code) which is substantially the 2009 IBC (International Building Code). As the State of Oregon adopted the 2014 OSSC July 1, 2014, hopefully these plans will be taken down and no longer be available to the public.

The plans do limit wind to 80 mph (miles per hour) as a fastest mile wind or 95 mph as a three second gust, which aligns with Table 1609.3.1 of the 2010 Code. http://publicecodes.cyberregs.com/icod/ibc/2009/icod_ibc_2009_16_sec009.htm

The 2012 and later Building Codes now utilize Vult for wind speeds and design.

Rather than pick apart these plans, I am going to focus on one item only, which is a fairly important one to post frame building owners, as we get asked frequently, “What size will my poles be”?

framed post frame These plans specify the bearing columns for the double trusses, spaced every 12 feet along the 36 foot sidewall as being PT 6×6 HF #2. For folks in the Eastern 2/3 of the United States, your treated columns are generally going to be Southern Pine. Southern Pine absorbs pressure preservative treating chemicals very well, it does not have to be incised. HF (HemFir aka Western Hemlock) not so much, it has to be incised, which reduces its bending strength by 20%!

Read more about incising here: http://www.hansenpolebuildings.com/2014/08/incising/

I entered the design parameters of the building plans, only I reduced the building eave height to 10’ from 14’. The resultant was it would take 6×8 HF #2 columns to support even this shorter building! (The 6×8 happened to be stressed to 71.9% of capacity – meaning a 6×6 would have been stressed to somewhere around 133%.

At 14 foot eave – 6×10 columns would be required!

Building Departments are well intentioned, but they, for the most part, do not have Registered Design Professionals (architects or engineers) on staff. Don’t put yourself or others at risk – I implore you, if you are going to construct a new pole building PLEASE do not utilize designs based upon prescriptive requirements because they ‘let you get by with it’. Build only from plans produced explicitly for you, upon your property, which were designed by a Registered Design Professional.

Adding Onto an Existing Building Endwall

Picture this…..

Your present pole (post frame) building is just not big enough. Whether through lack of planning on your part, or the previous owner – there just is not enough space.

So – just add onto the end of it. Simple, right?

Wrong.

Building EndwallAssuming the existing building endwall is fully enclosed, there is a very good chance the building was designed using what is called “diaphragm design”. If the existing building endwall steel (or structural sheathing) is removed, the entire building should now be reanalyzed by a registered design professional (RDP – engineer or architect) including the portion being added on.

This extra length can cause some unforeseen issues – shear intensity in the roof may be too great for the roof steel or sheathing, requiring some special design consideration in order to resolve.

The shear intensity also increases in the endwalls – not just the new endwall, but also the one on the opposite end of the building. This may necessitate having to reinforce one or both building endwalls with plywood or oriented strand board (OSB) sheathing in order to make them stiff enough to adequately transfer wind loads from the roof to the ground.

Special consideration needs to be given to the old endwall. Chances are the old corner columns are not sufficient in size to prevent failure due to wind loads. They may need to be reinforced or braced to prevent possible failures.

Trying to remove columns from the old endwall? Just because there is a truss on the end, does not mean it is designed for a clearspan. Often end trusses are designed to bear upon some or all of the endwall columns. If the existing building has dimensional lumber rafters as opposed to trusses, it further complicates matters.

What if there is an overhang on the existing building endwall?

If old and new portions of the building are the same width and eave height it could be possible to attach roof purlins from the addition to the fly rafter of the existing overhang with joist hangers.

No matter what the case – the more information which can be provided, the better. Plans for the existing building, as well as photos are always helpful, and be prepared to answer lots of other questions.

And – make sure to only add to an existing building endwall under the auspices of an RDP – a Registered Design Professional. The failure you save, may be yours!

How Should I Do Knee Braces?

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: Do you guys have any ideas or pictures on how one might want to finish off a pole building with knee braces? Thanks, GARY

DEAR GARY: Thank you very much for your question.

Our designs do not utilize knee braces, you can read why not here: http://www.hansenpolebuildings.com/blog/2012/01/post-frame-construction-knee-braces/

Your question is probably best addressed to the RDP (Registered Design Professional – engineer or architect) who originally designed the building, as they may have one or more of these issues with knee braces:

Not designed to support dead loads such as framing being placed between them to support a finished angled ceiling; having too much flexibility to support gypsum wallboard without cracking it; if adding a fairly rigid covering (such as OSB or plywood) making the assembly too stiff for the trusses to carry the imposed loads.

If you can stand the look – I’d suggest staining or painting the knee braces, as you will not negatively impact the structure.

Mike the Pole Barn Guru
DEAR POLE BARN GURU: Hello! What is a walk door? PAUL

DEAR PAUL: Also known as an entry or man door (or being politically correct a “person door”), is a pre-hung, hinged door allowing for access into or egress from a building by means of turning a lockset or pushing a “panic bar”. Most popular size is 36 inches in width by 6’8” in height. 48 inch and double doors offering a 72 inch width are also available as standard sizes.

Mike the Pole Barn Guru

DEAR POLE BARN GURU: I used too many screws in my siding on my Hansen Pole Barn. I need more to finish. Where can I purchase 1000 pearl gray 12x 1.5 screws? Dave

DEAR DAVE: It does happen every once in a while, however using too many is structurally better than not enough. Please contact Justine@HansenPoleBuildings.com and she will get your extra screws on the way!

Mike the Pole Barn Guru

Storage in Trusses

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday or Saturday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: My shop is in a 30×40 pole barn. I would like to put storage up in the trusses, and have some of the shelves that hang from the ceiling also (really there is no ceiling right now, just the trusses and roof). The trusses span the 30ft and I am worried about putting too much weight on them. I really would rather not have any supports in the middle of my floor…I was wondering if I could just sister up to the truss with some 2x6s or bigger to strengthen them…or should I just limit my upper storage? ONLY IN OHIO

DEAR ONLY: Unless specifically ordered for light storage loading, pole building trusses are rarely constructed so as to support any weight from their bottom chords other than limited electrical and lighting.

As you are considering “beefing up” the existing trusses, you should consult with the company which manufactured the trusses. There is typically a stamp on every truss with the truss company’s name on it. For a nominal fee, they can usually provide an engineered “repair” to upgrade your trusses.

In the event the truss company cannot be located, a Registered Design Professional (RDP – engineer or architect) should be hired to design a repair for you.

Only with one of these two solutions would I be able to recommend placing anything for storage in the truss system.

An alternative may be to build a raised “loft” floor in the building, at the level of, but not supported by the trusses. Again, this is a design best accomplished by a RDP.

DEAR POLE BARN GURU: Hello, I am contractor assembling one of your pole building kit packages.
Would you send me details for flashing the building please?
Need:
-Corner flashing.
-End capping the cut ends at top.
-Where do the corrugated foam strips reside?
-Roof panel overhang on the sides and ends.
-Door trim flashing

Thank you, WISHING IN WASHINGTON

DEAR WISHING: All of these are covered in depth in the Hansen Buildings Construction Guide which was provided to your client after purchase. If your client has not shared it with you, you should ask him for the big white binder which was sent to him. Every piece of trim has a diagram showing what it is along with the code used by the steel company. Detailed drawings show where each piece goes on the building.

The Great Purlins Caper

Here is the scene….

roof framing plansOur client has ordered a pole building kit package which is designed around sidewall columns spaced every 14’. For those who care, the building has a design roof snow load of 30 psf (pounds per square foot) and the actual roof dead load carried by the roof purlins (including the purlins themselves) is 1.626 psf. Our engineer designs a roof system with a pair of trusses at each sidewall column, and 2×8 #2 roof purlins joist hung between the trusses and placed 24 inches on center. The engineer prints off two sets of plans and supporting calculations, places his seal and signature on them, and sends them off to our client.

The client submits his plans and obtains a permit to build, which he proceeds to do.

Once under construction, the client sends this email to our office:

“My planning department made a notation on my plans that the roof purlins on the 14′ bays either need to be 16″ on center or use MSR 1450 rated lumber. The plans call out purlins 24″ on center and I don’t believe the wood I was shipped is rated MSR 1450. What is the resolution to this issue?”

The real issue, in my perhaps narrow mind, is a plans checker with perhaps limited ability to perform structural calculations, has made edits to an engineer sealed plan. Effectively, and probably unknowingly, this person has made themselves into the EOR (engineer of record) for this project, putting themselves and their Building Department into a potential position of liability should the building happen to fail structurally.

I wrote at length about this very issue earlier this year: http://www.hansenpolebuildings.com/blog/2013/07/building-official/

A couple of things to know about engineers (a broad generality of course) – their time does not come free, and they can get pretty bent out of shape when someone other than a Registered Design Professional questions their work.  After all, they spent considerable time and money getting their degree to be the “professional” assuming liability for every set of plans they seal.

In order to expedite a solution and keep the peace, I make a call to the plans checker. In the call I discover they have used 10 psf for the dead load on the roof purlins…..over six times the actual load! This sort of dead load would be much more appropriate for a building sheathed with OSB (oriented strand board) or plywood, with a shingled roof!

After a quick and happy conversation, the plans checker and I are now buddies, the crises is averted and the client is out building away on his building, using the plans as designed by the engineer.

Building Code: Things Which Make My Head Hurt

International Building CodeThe International Building Code (IBC) is the resultant of years of practical experience and sound engineering practice. The authors are a collective group of Building Officials and engineers, whose mission is to protect the safety of those who will be utilizing the structures built under the auspices of the Code. For practical purposes, every word, of every section of the Building Code has been scrutinized, analyzed, hashed over and rehashed to produce what can only be considered as a magnificent work. Even at this, amendments, additions and subtractions are proposed and made or rejected, providing an updated version every three years, which reflects changes which have come about from better science and research.

The Code also allows individual jurisdictions, to make local amendments to the Building Code. Oftentimes this is done without a sound engineering basis, or research to confirm the reasoning behind the amendment(s).

I am going to now pick upon a single permit issuing jurisdiction. This unnamed county has, as is their right, adopted the following:

15.16.060 Post Frame Structures (pole buildings).

A. Post frame structures over twelve hundred (1200) square feet in area shall be designed by a professional, licensed by the State of (Name Withheld) to design such buildings. The licensed professional shall affix his/her certification and signature to the design, including design drawings and details, specifications, and calculations. Any changes to the design, drawings, details, specifications, and calculations during review or construction shall be prepared and certified by the licensed professional designer of record and submitted for approval of the building official prior to incorporating such changes into the work. The minimum design criteria for post frame structures are as follows:

1. Minimum snow load is thirty-five (35) pounds per square foot (PSF). Reductions in live load/snow load are not permitted.

2. The minimum roof purlin dead load is 5 PSF.

3. The maximum total load deflection is:                       

 a. With ceiling: L/240

 b. Without ceiling: L/180

4. The maximum wall wind load deflection is L/120.

We recently had a plan review done, in this county, and the Plans Examiner/Building Inspector threw in this curve:

“Our standard design for accepting engineered plans for pole buildings over 1200 square feet, require that purlins/girts are spaced no more than 24” O.C.  Your plans call for girts spaced at 31 5/8” and purlins at 29 ¼”. “ 

After some discussion with the Plans Examiner the resultant was (as relayed from one of our owners):

They don’t have a 24” oc girt and purlin requirement – just the change to deflection that we looked at. His (building officials) reasoning was ‘experience’ – that engineers use code to under design buildings.

I will only address issues which I feel are either contrary to the Building Code, do not make sense from an engineering standpoint, or do not have a rationale under the Laws of Physics.

Minimum snow load. The Code addresses how to calculate Pf (flat roof snow load) and Ps (sloped roof snow load) based upon Pg (ground snow load) as well as factors such as Is (building importance), Ct (temperature factor – is building heated or not), Cs (sloped roof factor), and Ce (roof wind exposure factor).

Picking an arbitrary roof snow load, leads to the possibility of either gross over design (causing more cost to the building owner) or gross under design (leading to a possible failure).

As espoused by this jurisdiction, a roof for an Essential Facility (think fire station), which is unheated, has a 4/12 slope shingled roof, and is protected from the wind, would have the very same load as a heated storage building with an 8/12 pitch metal roof, which is exposed to the wind. Common sense says this is just not the case.

Minimum roof purlin dead load of 5 psf. The dead load should be set by the RDP (Registered Design Professional – architect or engineer) who designs the building to reflect the actual imposed loads. As 60% of the dead load is used to calculate the wind uplift forces on the building, an arbitrarily high dead load could result in the under design of the connections between purlins and trusses, as well as trusses and columns.  Potentially this could result in a design, by statute, which results in an overstress of these connections.

In reality 2×6 roof purlins at 24 inches on center, supporting a 29 gauge steel roof induce an actual dead load of about 1.5 psf (pounds per square foot). The 5 psf requirement is 333% higher than reality.

The Building Code allows for purlins supporting a light gauge steel roof to have a deflection of L/150, rather than the stiffer L/180. Deflection criteria have nothing to do with the structural integrity of the roof, merely esthetics under high loads.

The Code allows for wall girts supporting light gauge steel siding to have a deflection of L/90, rather than the stiffer L/120, as long as brittle finishes (such as plaster or drywall) are not being supported. Again deflection criteria have nothing to do with the structural integrity of the siding, merely esthetics under high loads.

Creating criteria which are counter to the majority of the jurisdictions in the country only creates confusion for RDPs, building providers and contractors, as well as increasing costs (without reciprocal benefits) to building owners. These criteria appear to be arbitrary and capricious in penalizing post frame construction against other forms of building construction.

If the feeling is the Building Code allows RDPs to under design buildings, then the jurisdiction should move the International Code Committee (along with providing rational proof as to why) to change the IBC. If snow load is their concern, the utilization of higher Pg values than have ever been historically seen (while not a reality), would allow for a uniformity of calculations by registered engineers.

Engineer – It Ain’t Amtrack

I once heard an anecdotal story about a man who had a choice to stand in one of two lines – for brains, or trains. He had always wanted to be an engineer, so he picked the line for trains….

OK, so it wasn’t necessarily funny.

If you’ve ever been involved with a commercial building, it was probably designed by a Registered Design Professional (an RDP – an architect or engineer). Ordered prefabricated wood roof trusses? Again, they were probably manufactured from designs created by a registered professional engineer (P.E.) or a structural engineer (S.E.).

In reality, virtually any structure was either designed by an RDP, or should have been.

Most architects subcontract the structural portion of their designs to an engineer. Engineers specialize in their ability to “run the numbers” to prove on paper why things will or will not perform in the real world.

An engineer is responsible for the analysis and design of the structure or framing system of a building or building component. While doing the building’s structural design, the engineer will take safety and performance into consideration.  For performance or serviceability this is the design for vibrations from machinery, floor vibration or deflection which could cause discomfort, or even building deflection or sway.  The occupants of a building might feel uncomfortable if the building sways or moves too much, especially on the upper stories.

An engineer’s qualifications can be verified.  The easiest thing to do is to check if the engineer has either a Professional Engineer (PE) license in civil engineering or their Structural Engineer (SE) license in the state which the project is being built.  Some states don’t offer a SE license so this is why there is a difference in the title.  While there is a nationally recognized test for engineers, there is no general licensing, it is state specific and each state has their own requirements to obtain and maintain registration.

Okay, so this is a general definition of the responsibilities of an engineer, how does it pertain to post frame buildings?  Pole buildings, for engineers, involve the same responsibilities and analysis as any other structure, but it all pertains to one specific material.  Very few RDPs are familiar with post frame construction and design pole buildings on a regular basis. If hiring an engineer to design a pole barn, look for one with extensive experience – hundreds of post frame buildings designed, not just five or ten.

Be wary of anyone (builder or company) who says “I’ve done pole buildings for 10 years,” but has no engineering background nor degree.  Does this mean he can verify the design he uses will be safe? Is it economical in design or did he just put a lot of lumber into it, many dollars of it which does nothing for the building and a lot for depleting your funds?  Does it have verifiable calculations to prove it will stand the test of time and nature?  Or does it mean buildings have been built over ten years and fortunately none of them have fallen down – yet?  Companies which supply complete pole building kit packages have ongoing relationships or employ engineers who have the expertise it takes to design safe and economical structures, which will perform admirably for generations.  Don’t be caught “un-insured”.  Make sure your building has an engineer’s stamp of approval on your building plans.