Tag Archives: building official

Dear Building Officials

Dear Building Officials

I have met (either in person, via phone or technology) more than just a few Building Officials, Inspectors and Plans Examiners over my nearly four decades of post frame buildings. I have even been privileged to be a guest speaker for several groups of these fine folks, regarding Code conforming post frame construction. My expert opinion – collectively folks who work in Building Departments most genuinely go above and beyond their call of duty to assist building owners in building safe structures.

Several members of Building Departments are either subscribed followers of this column, or regular readers of it via Linkedin posts. These are most likely ones who are providing excellent service to those venturing into their offices.

My most recent two articles covered questions we require our clients to ask of their building officials in regards to pre-construction of a new post frame building. With these answers in hand, we can assure our contracted Registered Professional Engineers have data necessary to design, meet or exceed structural requirements.

Unfortunately, there does not exist a central clearinghouse database for structural design criteria by jurisdiction. For builders and RDPs (Registered Design Professionals) who provide services over more than just limited geographical areas, this would be a tremendous tool.

Now I do have a “hero” building department and will give them kudos here. Kittitas County (Washington) Community Development Services provides a parcel-by-parcel load analysis covering their minimum design requirements (https://www.co.kittitas.wa.us/cds/building/cgdc-form.aspx).

Many building departments have posted climactic design requirements in their websites. When kept up to date, we find these to be quite handy. I would imagine RDPs appreciate availability of this information.

Recently, one of our clients in Wisconsin was facing a challenge – their Building Official would not provide them with minimum loading requirements for their proposed new building! Although rare, I have seen this occur before. In one instance, I had a Building Official refuse to provide accepted loading information. Instead they wanted us to submit engineer sealed plans and then they would tell us if what we had guessed for loading was correct or not!

Why this information was withheld baffles me. In some cases (especially where permits are issued without any sort of structural plan reviews) it could be a permit issuing authority just frankly does not know!

In my humble opinion, an expedient way to streamline permit acquisition processes would be to have readily available design criteria. For sake of public safety, I also feel all building plans not falling under prescriptive code requirements should be produced by a Registered Design Professional.

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.

The Case of the Termite Shields

When it comes to post frame building construction, I know a little bit about a lot of things. I get asked a lot of questions about how to solve post frame building challenges and do a pretty fair job of answering them. When I do not know an answer I feel confident in, I have no problems with doing the research or reaching out to an expert. Such was the “Case of The Termite Shields” (sound almost like a Sherlock Holmes story).

In this case, I went to “The Bug Doctor” Jerry Schappert of www.pestcemetery.com

Here was my question:

mr owl tootsie roll pop“We have a Building Official asking for a termite shield for a post frame (pole) building. The building utilizes pressure preservative treated columns embedded in the ground with a treated splash plank around the base of the walls. At the bottom of the steel wall siding is what is known as base trim, it is steel and extends outward from the splash plank 1-1/2″ with the outer edge being a downward bent lip. This should serve to function just like the steel termite shields we have viewed online. 4-5/8″ of the pressure preservative treated splash plank is visible below the base trim. There is a product called a plastiskirt which is vinyl and designed to wrap the splash plank. In your opinion, what would be the best design solution to protect the building from termites as well as to meet the requirements of the Building Code?”

The good doctor replied (in very short order I might note):

It sounds to me you’ve met the code already? What more does he or she want?  There are ‘pipe shields’ on the market but they are just basically what you describe. Pole barns here in Florida basically have very little code requirements and we are the termite capital of the world.  So without knowing what more the inspector is looking for I wouldn’t know how to answer.

Need a bug expert, try Jerry. Need a post frame building expert? I will give my best impression.

 

Don’t Build Without a Building Permit

ASK THE POLE BARN GURU is for everyone – those who own, or hope to own, a pole building, contractors as well as Building Officials. Here is a real life interaction with a Building Official:

“I have a customer erected pole barn 50 x 60 and very concerned with 50 foot span engineered trusses resting on 2 x 12 nailed to the sides of 4 x 6 posts at 8 foot o.c.

Please respond, my email is xxxx and I can forward some photo graphs. I am the building code official here in xxxx, and this building was erected without a design drawing.”

 Mike the Pole Barn Guru response:

“Thank you for reaching out to me, I’d be happy to assist in any way possible. Any photos would be appreciated, as well as the sealed truss drawings.”

And back to The Pole Barn Guru from the Building Official:

“Thanks for the prompt reply.

Attached is the sketch used to construct this building (no stamp, this sketch was hand drawn by the sales rep supplying the trusses).

Also attached are the Truss Design Drawings.

Also attached are a few photos of the building and the truss support at the wall line.

Get a Building PermitMy concern is the structural integrity of the 2-2×12 (separate, not fastened together as a beam) nailed into the side of the 4 x 6 posts at 8 ft. o.c.

The shear stress on the nails thru the 2 x 12 into the posts seems to be the weak point of the load path.

 I would expect an LVL beam set into notches or on top of the posts to carry the load.

 In addition, I do not see any lateral bracing of the walls, other than the metal siding attached to the purlins.

 I am looking to get a feel if this design is close to being adequate or if there is a real problem here with weak framing.”

I’m on the road today, so won’t be able to get more complete answers to you as quickly as I would like.

One problem I am seeing right away, the roof trusses are designed to be placed 2′ o.c. but they are 4′ o.c.

It appears wall height is somewhere around 16′ – would this be a correct guess?

Just a quick opinion – this building has some serious problems. In the end – my recommendation is going to be for them to provide engineer sealed drawings (wet stamps and signatures) to verify the building as built (or with numerous corrections) is adequate to support the imposed loads.

More later ~ Mike the Pole Barn Guru

And here is my more detailed response:

Here is a more complete list of issues/potential issues with the pole building:

I’ve used the wind speed (Vult) of 110 mph as listed on the truss drawing. I feel this is in error and it should probably be 115 mph. I also assumed an eave height of 16′.

Sidewall column footings need to be a minimum of 30″ in diameter in order to support loads as listed on the truss drawings (assumes soil bearing capacity of 2000 psf) and should be a minimum of 6 inches thick.

Provision needs to be made to prevent column uplift.

The columns at 8′ on center appear to be three ply 2×6 glulams – depending upon the manufacturer, they may be adequate.

It appears the wall girts are 2×4. Spaced 24″ o.c., it would take 2×6 #2 to adequately support the wind loads given the Code requirements for deflection.

While they do not have to be fastened together, the (2) 2×12 truss carriers are inadequate to support the loads imposed by the trusses. A (4) ply 2×12 #2 SYP carrier would be adequate and would be stressed to 95.6%. A 1-3/4″ x 11-7/8″ 2800f LVL would also work. Connections are going to be an issue here – I ideally like to see the carriers notched into the columns, as then uplift becomes the force to be reckoned with. Each truss is placing 5200# of force on the middle of the 8′ truss carrier span.

Other than the front endwall, the walls (if adequately fastened with the correct size screws) will carry the shear loads without the need for further bracing. The front endwall must resist 3771# of shear force – which is impossible to do with diagonal braces – as enough fasteners cannot be placed in the ends of the braces to resist the imposed loads. Plywood or OSB shear walls should be added at the corners.

My real concern is with the trusses. The drawings submitted show the trusses spaced every 2′, yet they are installed every 4′. The truss drawings specify a 2x6x12″ 1650msr bearing block to be applied to each heel of each common truss, yet they do not appear in the photos provided. Truss drawings specify bottom chord bracing to be every 2’2″ in lieu of a ceiling as well as continuous lateral bracing on the longest diagonal truss web.

All doors should be verified for the ability to resist the applied wind loads, else the building will need to be treated as “partially enclosed”, which is just going to compound the issues.

In my humble opinion, the best bet is for the building owner to hire a registered professional engineer to design fixes for his building…and get a building permit.