Tag Archives: pole barn truss spacing

Truss Spacing for Shingled Roofs

Roof truss spacing seems to be a topic with no consensus. Most Americans live in traditional stick framed houses, apartments or condominiums, where roof trusses (if they were utilized, rather than using dimensional lumber rafters) are most typically spaced every two feet.

Reader CHARLIE writes:

“Dear Hansen Pole Buildings, May I ask how far apart was the Truss placement in your “Re-roofing with Shingles” article? 

https://www.hansenpolebuildings.com/2012/01/re-roofing-with-shingles/

I’m considering a 24’x 36’ pole barn for a recording studio build but would need asphalt shingle type roof. I’m concerned that a suitable design would need additional rafters to meet the 7 lb/sq ft load requirement.

Most designs I have seen are showing the trusses 4’ OC. 

Respectfully, Charlie”

Mike the Pole Barn Guru writes:
In this particular article roof trusses were actually spaced with a pair every 12 feet – directly aligned with sidewall columns. This style of post frame construction affords several advantages:

Fewer holes to dig. There is nothing more deflating than getting down to digging one or two last column (pole) holes and hitting a rock larger than a Volkswagon Beetle! Minimization of holes to be dug reduces chances of underground surprises.

No need for truss carriers (structural headers) between columns in order to support trusses. Structural failures are almost always due to connection issues. Truss carriers rarely have adequate fasteners from header to columns and trusses themselves are rarely anchored sufficiently to them.

By far my most read article of all time has been on pole barn truss spacing: https://www.hansenpolebuildings.com/2011/06/pole-barn-truss-spacing/.

Asphalt shingles need to be installed over asphalt impregnated paper (felt) or ice and snow shield, most usually over OSB (Oriented Strand Board) or plywood. Weak link of this system is spanning ability of this underlying sheathing.

In order to be within spanning capabilities of common sheathing, dimensional lumber roof purlins, on edge, were joist hung between truss pairs, every two feet.

When you order a post frame (pole barn) kit from Hansen Pole Buildings with asphalt shingles, we automatically have our engineers design for this added load, as well as reducing deflection criteria so you end up with a nice, smooth roof. We also take into consideration Building Code requirements to account for a future overlaid reroof (even “lifetime” shingles will not last anywhere near a lifetime).


Considering a shingled roof due to how long they are warranted? You might want to read this article first: https://www.hansenpolebuildings.com/2015/03/shingle-warranties/.

Torn Between Two Lovers

In reader JEREMY from GOSHEN’s case, he is torn between two methods of post frame construction, rather than one hit wonder Mary MacGregor’s 1976 tune “Torn Between Two Lovers”. 

JEREMY wrote, “I’m torn between trusses on 4′ centers and what you do the double trusses every 10 or 12”.

Mike the Pole Barn Guru says:

It can be a tremendous pressure to build ‘just like everyone else does’. Because if everyone else is doing it a certain way, then it must be right. Right?

I can assure you trusses placed every four feet is merely how most builders in your area choose to assemble their buildings. In much of post frame construction’s world, engineers, architects and builders happen to place double trusses every 10 to 14 feet, with 12 feet happening to be most common. From a structural aspect, I prefer this wider spacing and doubled trusses. Every pair of trusses rests securely into a notch cut into columns. This physically makes it impossible for a truss to slide down a pole. Trusses are physically connected to each other face-to-face. This reduces risks of one single truss having a weak point, failing and pulling the rest of the roof down with it. With trusses ganged in this fashion, need for lateral bracing of truss chords and webs is reduced.

All roof purlins are connected to truss sides with engineered steel hangers. Trusses on carriers (headers between columns) often have under designed connections – not enough fasteners from carrier to column and truss to carrier. Nailed connection between purlins flat across truss tops is also problematic and in most instances is inadequate to resist design wind uplift loads. (more about this subject here: https://www.hansenpolebuildings.com/2014/04/nationwide-2/) Most post frame buildings with columns every eight feet also have ‘barn’ style wall girts – placed wide face to wind on column faces. Other than in very low wind applications and sheltered sites are these adequate to meet minimal building code wind loads. To read why girts installed this way fail to meet Building Codes please read https://www.hansenpolebuildings.com/2012/03/girts/.

From an aspect of ease of construction – wider spacing means fewer holes to dig (worst part of any post frame building). It reduces the total number of pieces having to be handled by roughly 40%. It makes it possible to assemble entire bays of roof on the ground and lift or crank into place using winch boxes. Safety and speed are paramount to how I prefer to build, being able to do this much assembly on terra firma meets both of these requirements.

Blog Review by an Expert

I’m a seat of the pants journalist – my training was as editor of the Post Falls High School newspaper back in 1975! This blog is one of several finalists in the 2017 Best Construction Blog competition. In the event you have been entertained or have learned from my articles, your vote would be appreciated at: https://constructionmarketingideas.com/the-pole-barn-guru-blog-how-to-combine-business-and-technical-insights/ (scroll to bottom of page).

Mark Buckshon of www.constructionmarketingideas.com penned this review of my blog, which I will share with you:

The Pole Barn Guru blog: How to combine business and technical insights

By Mark Buckshon

March 8, 2017

 

The Pole Barn Guru blog

Mike Momb‘s Pole Barn Guru blog for Hansen Pole Buildings, LLC demonstrates how a business can combine marketing, technical support, and business insights into an effective blog.

This Minnesota-based business specializes in prefabricated kits for “pole buildings,” which can economically serve as barns, garages, storage sheds, and even homes. It just takes a few weeks from order to delivery — the website offers several standard models for shipping, and a custom-design ordering service.

Blog topics include follow-up customer service reports, technical question answers, and some business insights and history.  I especially enjoyed reading Momb’s description of how he got the business started in the early 80s just as the major Reaganomics recession at least temporarily virtually ground the housing business to a halt (when interest rates soared above 20 per cent).

This post describes how Mike Momb started the business from scratch.

With my final paycheck, I was able to pay our family bills current and had $50 left over. The local “free advertising” paper would allow me 3 weeks of credit, if I paid for the first week’s ad up front.  I decided I couldn’t do any worse than the people I had worked for, and right then decided I was going into the pole barn kit business. Now granted, I had no business location, no inventory, no truck, no anything….all I had was an ad in the local free newspaper!  The first week I sold three buildings, got down payments from the clients and… I was in business! One of my friends was in real estate and located six acres of highway frontage on Highway 99E just north of Canby, Oregon which could be rented reasonably.  Paying first and last month’s rent, I now had a place. The Chevrolet dealership had ordered a lumber delivery truck for the local yard, who had not taken delivery on it. With a small down, they got me financed on the balance and I could deliver. M&W Building Supply Company was a reality!

This entry has had more than 50,000 views to date. The top post (with more than 100,000 views) is Pole Barn Truss Spacing.

A recent post describes an interaction with a client concerned about the building’s capacity for load bearing and wind. in Panic Mode, We’ve All Been There, Momb provides clarity in explaining the standards and that the building will meet the requirements — but if the purchaser wants to pay more, the higher load factors could be accommodated for an upgrade fee. What I like here about this example is how he takes a real situation that may apply to others and demonstrates thoughtful and comprehensive research and knowledge in answering the questions.

Overall, this blog does what it should: I’m sure certain entries/posts have good search engine traction; leading potential clients to the company to begin the relationship. And if you already are a client, the blog reassures you of the business’s values, traditions, and service focus.

You can vote for The Pole Barn Guru blog and others of your choice on the ballot below. Voting concludes March 31.

The kindest of your vote here is greatly appreciated: https://constructionmarketingideas.com/the-pole-barn-guru-blog-how-to-combine-business-and-technical-insights/