Tag Archives: engineering

Top Chord Repair, Little Voices, and Building Use

Today the Pole Barn Guru tackles questions about repairing a rotted top chord of an existing truss, a little voice in a contractor’s head, and the use of an existing building on newly purchased parcel.

DEAR POLE BARN GURU: When we bought our property the pole barn on it already had a rotting roof with a hole in it. We are ready to re-roof it, are putting steel roof on it, and two of the truss’s top chords have rot we think they need to be replaced, is there a easy way to get the truss apart to fix this? We are fairly handy people but new to dealing with truss repair. Would appreciate any input. JILL in SOUTH LYON

DEAR JILL: You are good to address this issue now. There is no way to easily take apart a prefabricated wood roof truss when it is in place. Your best bet would be to contract with a Registered Professional Engineer in your area who can do a physical examination and provide an engineered repair.  This is just prudent as if there was to be a future building failure at a non-engineered fix, your insurance company could deny your claim.

If your building has purlins over top of trusses, it may be something as simple as adding another top chord to one or both sides of damaged trusses and bolting through.

 

DEAR POLE BARN GURU: My client has some old metal trusses. 1 1/4 angle iron top and bottom threads with 1” solid rod cross members 1” high and 28” long.

They are not plated and angled on one end to accommodate mating in the center for a 2/12 pitch roof. They appear maybe to be old single slope trusses or maybe floor trusses. Try angle out the last 4’ on both ends with the top chord and the bottom chord stops.

Anyway he wants to cut and weld clips in the middle to accommodate 2/12 pitch mating surface and on the wall end weld on clips to catch the post.

I’m okay up until he says he only has enough for 7 of these trusses to be made (14 total pieces). He is demanding we put these small trusses on 16’ centers. Use fresh cut true 2×6 milled lumber (ungraded).

No overlaps at the trusses just flush up the ends at each post. No end walls only sidewalks, 18’ high and no plans for lateral supports inside the Trusses running length of the building.

I haven’t built but a few barns all engineered so haven’t had any problems but worried about this red neck engineering. Also no center post clear span 40ft with 4’ overhang past the post. 7 post each side 16’ o/c truss span.

LEE in LIVINGSTON

DEAR LEE: Obviously a little voice inside of your head is telling you to run, do not walk, away from this as quickly as possible. I agree with your little voice. There are plenty of clients out there who want to do things correctly, if you do take this mess on and it fails – you are going to be hung out for it.

 

DEAR POLE BARN GURU: I have recently purchased a five acre parcel with a 40×40 post frame building on it the guy that we bought the property from had this building put up with the idea of making it his home. The trusses are built to have living areas upstairs, it is raw, posts, roof trusses, and metal siding but no plywood under the metal and the posts are back filled construction. I want to do a wood floor just not span forty feet instead do floor joists of twenty feet so my question is can I build from the raw state that it’s in like you would for a normal stick built home or would I need to pour a regular foundation first?. Thank you. JOEL in POCATELLO

stick frame building collapseDEAR JOEL: Hopefully your ‘guy’ bought a fully engineered building, designed for R-3 Occupancy Classification and Use, Risk Category II with deflection limits of L/240 or greater for walls and truss supported drywalled ceilings. All of these will be specified on this building’s engineered plans. If you do not have a set of them, your Building Department may have them on file.

If you are unable to ascertain these conditions, you should retain a Registered Professional Engineer to do an analysis of your building for structural adequacy for your intended use. He or she can also make a determination as to if column footings are adequate to be able to support weight of your raised wood floor. You should not have to go to an extreme, such as pouring a regular foundation.

You may want to reconsider your floor joist span as 20′ will take 2×12 #2 at 12 inches on center and will have an allowable deflection at center of 2/3 of an inch. By having interior supports closer together you can greatly reduce joist dimensions and deflection, increase joist spacing and have a much less costly floor.

 

 

 

Gothic Arch, Steel Board and Batten, and Engineering Services

This Monday the Pole Barn Guru discusses Gothic arches, steel board and batten, and engineering services.

DEAR POLE BARN GURU: I am going to build a 24×36 barn and have become infatuated with the Gothic arch roof line from looking at existing arch roofed barns in my area (one is amazing…built in 1911). Any thoughts on using laminated arches in conjunction with a pole barn? The walls would be 10′ tall with the arch reaching to 28′ tall. If the end poles (8′ spacing) were extended to reach the arch, they would need to be 25′ tall. Thanks. DUSTIN in LLOYDMINSTER

DEAR DUSTIN: My first experience with gothic arches were those built in the 1970’s by Red Waggoner in North Idaho. He used Construction Adhesive to glue 2x4s into arches (of course with no engineering). In West Central Minnesota, there are many of them – none of recent construction. In order to keep arch bases from spreading, they would need to be anchored directly to a concrete foundation, piers or somehow attached to a wall-to-wall floor. While they look neat, I am doubtful they would be a viable design solution combined with post frame.

 

Affordable horse barnDEAR POLE BARN GURU: Is steel board and batten an option for pole barn construction? BRITTANY in MILLRY

DEAR BRITTANY: Steel board and batten siding is an option for post frame construction. It will be significantly more expensive than standard through screwed steel and should be installed only over a solid substrate such as 5/8″ CDX plywood.

 

DEAR POLE BARN GURU: Hi there, I am developing a plan for a 1.5 story small cabin and would like to build with a pole structure, with poles on cement pads or perma-columns and a wooden raised floor. I have been thoroughly enjoying your blog posts and thought I would write to ask about your services. I’m not looking for a kit or premade plans but could use some engineering guidance based on the basic design that I’ve put together for an ~18×20 structure. Do you guys offer that kind of service, with hourly rates or otherwise?

Thanks and I hope to hear from you soon! BEN in OAKLAND

DEAR BEN: Thank you very much for your kind words. Due to liability issues we are unable to offer this sort of service. You might try reaching out to one of our independent third-party engineers John Raby (john@raby-assoc.com) to determine if he would have an interest in assisting you.

 

Where Your Barndominium Dollars Go

Where Your Barndominium Dollars Go

Recently published by NAHB (National Association of Home Builders) was their 2019 Cost of Construction Survey. I will work from their ‘average numbers’ to breakdown costs so you can get a feel for where your barndominium, shouse or post frame home dollars go.

Please use this as a reference only, as chances are your barndominium, shouse or post frame home will be anything but average!

2019’s average home had 2594 square feet of finished space and a sales price of $485,128. Without lot costs, general contractor’s overhead and profit actual construction costs were $296,652 ($114 per square foot).

Construction Cost Breakdowns as Follows:

Site Work

Building Permit Fees                                                                                  $5,086

Impact Fees                                                                                                   3,865
Water & Sewer Fees                                                                                     4,319

Architecture, Engineering                                                                           4,335

Other                                                                                                                 719

                       Foundation

Excavation, Foundation, Concrete, Retaining walls and Backfill        $33,511

Other                                                                                                                1,338

                     Framing

Framing (including roof)                                                                            $40,612

Trusses (if not included above)                                                                     6,276

Sheathing (if not included above)                                                                 3,216

General Metal, Steel                                                                                           954

Other                                                                                                                     530

                       Exterior Finishes   

Exterior Wall Finish                                                                                   $19,319

Roofing                                                                                                          9,954

Windows and Doors (including garage door)                                       11,747

Other                                                                                                                671

                       Major Systems Rough-Ins       

Plumbing (except fixtures)                                                                        $14,745

Electrical (except fixtures)                                                                           13,798

HVAC                                                                                                               14,111    

Other                                                                                                                 1,013

                       Interior Finishes       

Insulation                                                                                                  $ 5,184

Drywall                                                                                                        10,634

Interior Trims, Doors and Mirrors                                                           10,605

Painting                                                                                                         8,254

Lighting                                                                                                         3,437

Cabinets, Countertops                                                                             13,540

Appliances                                                                                                    4,710

Plumbing Fixtures                                                                                       4,108

Fireplace                                                                                                       1,867

Other                                                                                                                923

                                              Final Steps

Landscaping                                                                                              $6,506

Outdoor Structures (deck, patio, porches)                                           3,547

Driveway                                                                                                     6,674

Clean Up                                                                                                     2,988

Other                                                                                                              402

Other                                                                                                      $11,156

Considering using post frame construction, rather than stick built and foundation costs will decrease by roughly $10,000 (https://www.hansenpolebuildings.com/2011/10/buildings-why-not-stick-frame-construction/).

Architecture, Engineering, Framing and Exterior Finishes for this average home run an astonishing (to me) $97,614. If labor runs 60% of material costs, this would put a material package at $58,300! At over $20 per square foot, this would be one very, very nice post frame barndominium!

Looking to stretch your barndominium dollars? Considering Doing-It-Yourself, you absolutely can do it!

Correct Pole Size, The Better Building Size, and Drip Edge Placement

The Pole Barn Guru assists with questions about pole size, the “right” sized building, and a picture is worth a thousand words.

DEAR POLE BARN GURU: I have a question on a pole barn.  I’m thinking of 50 by 60 and about 14ft high or so.  On the 4/4 poles, how far apart should they be.  Also on the headers, that are at the top and go all the way around, are they usually 2 by 8?  Thanks, JOE in BOWLING GREEN

DEAR JOE: Hopefully you trust me enough to believe I will steer you in a correct direction, because you are heading in a wrong one. Only one right way exists to get answers you seek, to order yourself a post frame building kit package with plans sealed by a registered design professional (RDP – engineer or architect) specifically for your building (not a generic photo copy). Done right – there will be no need to have headers all around your building, as double trusses should be placed directly to bear upon columns, insuring best possible structural connections. As to columns, they will need to be much larger than 4×4, regardless of how far apart they are spaced.

DEAR POLE BARN GURU: I am trying to design a small hard apple cider production building. It does not need to have a retail portion; that is elsewhere at our farm; just a convenient 20×30 work room that can accommodate lots of washing/spraying down of equipment, temperature control, allow vehicle entry for loading/unloading, and some viewing windows for customers to see the process. Do you have some plans/designs/kit for such a building?

Thanks and kind regards, TOM in ROSE HILL

Hansen VisionDEAR TOM: You’ll want to make certain your proposed 20′ x 30′ area will be adequate for all of your needs. You may find increasing building footprint to say 24′ x 36′ to not be significantly more expensive of an investment, whilst providing 44% more space. With every building we provide being a custom design to best fit client needs, we can certainly provide exactly what you are looking for. A Hansen Pole Buildings’ Designer will be in contact with you shortly.

 

DEAR POLE BARN GURU: 14 foot side wall panels with 2×8 skirt, what is my measurement on the skirt either from top of skirt or bottom to install my rat guard, I will have a 12 inch overhang (eaveside) using fj channel. CARL in NEWAYGOl

DEAR CARL:

 

 

 

 

Dry Set Brackets on Foundation, Unfinished Jobs, and Engineering

Today the Pole Barn Guru discusses rebuilding on an existing concrete foundation with dry set brackets, unfinished work, and proper engineering.

DEAR POLE BARN GURU: I’ve recently torn down an old machine shed that still has very good 8″ wide by 24″ deep cement foundation walls that I’m thinking about using to erect a new pole barn/machine shed.  Only about 6″ out of the 24″ of the foundation wall is above ground.  Can I erect 4×6 or 6×6 posts to the existing foundation or should I use more of the stick framing techniques?

One additional question on this:  The previous machine shed had a sole plate on the foundation.  Would you normally use a sole plate in a situation like this as well or just attach directly to the concrete? What’s the advantage of using a sole plate?  If I were to use a sole plate and anchored it to the foundation, and then put the posts on top of the sole pate, how would you recommend attach them to the sole plate?

Thanks, MICHAEL

DEAR MICHAEL: Regardless of design solution chosen, it would prudent to have your existing foundation reviewed by a competent local engineer for adequacy. In many areas frost depths are deeper than your foundation, rendering it unable to be reused. Provided your concrete has sufficient depth and strength, a post frame building can easily be mounted to it using dry set anchors (https://www.hansenpolebuildings.com/2014/12/dry-set-column-anchors/).

Bracket manufacturer shows anchors mounted directly to concrete walls and I would imagine this achieves best possible connection without creation of additional hinge points due to sill plate thickness. Sill plate still in place upon top of existing concrete wall, then I would recommend it being cut away where brackets will be located.

DEAR POLE BARN GURU: I had contacted you before regarding a kit but decided I didn’t want to get into a project that big.  I contracted with a local builder from Idaho Falls, Idaho to build my building in Afton, Wyoming.  He seems to have disappeared after setting the posts and framing in the wall girts.  Since he builds very similar to your kits I thought I might inquire to see if you could sell me a partial kit.  What I have is 6×6 posts on 12 foot centers and as I already said, they are framed in with 2×6 girts.

contractors-workingI noticed on your web site you have some buildings in Wyoming.  Do you use vendors for regional distribution?  I can’t imagine shipping everything from MN. JOHN in AFTON

DEAR JOHN: I hate it when a builder pulls things like this it just makes our entire industry look bad. We’ll need specifics of dimensions and features to price balance of your building, as well as what materials you actually have delivered. We have distribution agreements with vendors all across country in order to maximize possible providers and minimize costs of shipping. Your Hansen Pole Buildings’ Designer will be reaching out to you shortly.

 

DEAR POLE BARN GURU: For the post on top of a foundation wall would you recommend 4″ x 6″ or 6″ x 6″ post and would they need to be treated?

Thanks, MICHAEL

DEAR MICHAEL: Second part of your question gets answered first, it would only need to be pressure preservative treated if wood was in contact with concrete. As most commonly available timber sizes are pressure preservative treated, you might very well find treated timbers to be both more readily available and more cost affordable.

As far as size of column – this should be determined by an engineer hired to design your building (or engineered plans provided by your post frame building kit provider). Post size will be influenced by heights of both walls and roof, design wind speeds and wind exposure, snow loads and many other variables. Please do not just take advice from some layperson when it comes to your building’s structural design, rely upon a registered design professional.

 

 

Wrapped the Wrong Way, Services, and Ceiling Liners

DEAR POLE BARN GURU: I bought a home that has a newer pole barn (40×56, laminated 6″x6″ posts 8′ o.c…. 12′ walls) and the entire barn is wrapped with bubble wrap between the metal and perlins / girts. Would it be acceptable to frame 2×4 walls, and place bat insulation in the stud spaces? I ask because the concern I have is having a vapor barrier (bubble wrap) on the outside of the wall rather than on the inside, as with standard construction. Wall construction would be like this; interior sheeting (drywall, plywood, and ribbed interior metal), paper backed fiberglass insulation between framed wall set between posts flush to the inside, bubble wrap, metal exterior sheeting. Thanks for any advice, as I can’t get a straight answer from local contractors. Sincerely, TRENT in LEXINGTON

DEAR TRENT: I will give you the straight answer, because I have no skin in the game. All I care about is you get the best possible building for your investment.

The answer is you need to either get the bubble wrap out of your walls, or poke numerous holes in it so moisture does not become trapped in the insulation cavity. Personally, I would remove the wall steel, one wall at a time. Pull out the radiant barrier, replace it with Tyvek or a similar performing building wrap, then put the siding back on. While it sounds daunting, it should actually go fairly quickly. I’d use BIBs insulation in the walls with a six ml clear visqueen vapor barrier on the inside of the framing.

DEAR POLE BARN GURU: Hello, this question seemed kind of answered in your FAQ, but I wanted to take a moment and ask anyways, as your website really seems to convey desire to work with the customer as well as a care for quality.  I’ve loved reading the Questions to the Guru!

Without getting into too much detail, I have acres of Loblolly Pine that I will be building an Event Center Barn out of. I’ve got a miller who’s working at some really great rates.

Ask The Pole Barn GuruI’m looking for an engineer to put all my thoughts on the barn together and stamp em so I can get going on the permit process.

Do you all provide JUST the engineering service, I wouldn’t be buying any material from you all, but I would of course supply all the information on the materials I’d like to use, look of it, etc.

If you all don’t, do you think one of your engineers might be interested in privately contracting it?

Again, I ask only because you all seem like a great organization.

Thanks for your time! JACOB in OJA

DEAR JACOB: Thank you very much for reaching out to us. Top quality is a high priority to us.

We and our engineers do not provide just engineering services, due to the inability to control the quality of materials which go into the completed project.

A concern about your choice of building materials – your Loblolly Pine should be both dried to a moisture content of 19% or less and be grade stamped in order to be used in an engineered building. You are probably ahead of the game to sell your timber and purchase the lumber with the proceeds of the sale.

DEAR POLE BARN GURU: Hello, when installing tin to the ceiling in a pole barn. Do you want to run the full length of the building? Or should you run left to right with your sheets of tin? The building is 60×120. RYAN in WYOMING

gymnasiumDEAR RYAN: It will depend upon how you are supporting the liner panels. In our typical buildings, with double trusses spaced usually every 12 feet, we place joists every four feet between the truss bottom chords and run the steel the width of the building. If your trusses are spaced every four feet, you could safely attach the steel to the bottom of them and run the length of the building. I have heard of cases where trusses have been spaced every eight to 10 feet and people have attached the liner length of the building to the bottom of the trusses with no other framing supports. Personally I feel the deflection of the steel between trusses would be unsightly.


 

Engineered Pole Barn

This is Why Pole Barns Should be Engineered

A line of strong thunderstorms moved through North Central Florida Saturday March 23, prompting severe thunderstorm warnings and a tornado warning.

The photograph is of the remains of a pole barn, which is suspected to have been hit by a tornado. No other structures in the area were destroyed, however there were reports of severe hail damage to the siding and windows of one manufactured home.

Luckily the eight horses who were housed in this barn survived.

fallen pole barnOf course I am not able to personally visit the site to examine the damage forensically, however I can make some observations, which leads me to suspect this particular destruction was as much due to poor design, as it was to having been hit by high winds. If it had been an engineered pole barn, my educated guess is the damage might have been been minimal, if not “fixable”.

Look first at the building columns – leaning every which way. They did not break off from the wind, but are in pretty much every direction other than being plumb. This tells me they did not have any concrete around the bases of the columns, which would have kept them upright.

The columns are notched on the outside – which is a sign there was once a truss carrier (a beam from column to column to support the trusses) in the notch. As no truss carriers are yet in place, the connection between the columns and the truss carriers was obviously inadequate to withstand the uplift forces.

Connections are always the weak link in any structure. Every once in a while, the History channel will show a segment on building failures – and it is nearly always the fault of under designed, or under sized connections.

While a properly engineered pole barn may not have survived the full onslaught of a direct hit from a tornado, the chances of damage being minimal would have been far greater had a registered design professional been involved, and his or her plans followed.

Don’t take unnecessary risks with valuable property and animals.  Seat-of-the-pants design is rarely adequate.