A Case Study on Advantages of Post-Frame Residential Construction
Originally published by: Construction Magazine Network — October 8, 2014
The following article was produced and published by the source linked to above, who is solely responsible for its content. SBC Magazine is publishing this story to raise awareness of information publicly available online and does not verify the accuracy of the author’s claims. As a consequence, SBC cannot vouch for the validity of any facts, claims or opinions made in the article.
Residential post frame remains a modest part of the industry, but as with all things post frame, it continues to evolve. From secondary garages with living quarters to full-time residences, builders are finding converts among consumers who are looking to build their dream homes.
In the September issue of Rural Builder, we took a look at two post-frame residences that are the types of post frame that stand testament to its design flexibility. Both are post-frame homes built by and for post-frame builders.
Builders Josh Sweinhart; and Mike Momb, the writer behind our “Behind the Hammer” column, offers some market insight, construction tips, and first-hand experiences on residential post frame based on their own home-building projects.
You will notice that Mike’s article (below) frequently refers to his pole barn home. Before you cringe too hard at the term pole barn home, consider what I found online. Pinterest is a website where people post and peruse photos of their favorite things. I visited to see if there was any mention of post frame. Yes, there is, but it appears that the term pole barn home is more recognized among site users.
Doing a general search on the Internet yielded similar results. Professional building companies leaned towards post frame but consumer sites leaned towards pole barn.
And quite honestly, it makes sense. The average consumer understands the term pole barn and a pole barn home certainly offers intriguing possibilities. Some consumers are following that intrigue to discover the amazing possibilities of post frame.
So before you become too judgmental, just remember your Shakespeare: “a rose by any other name would smell as sweet.”
– By Sharon Thatcher, Editor, Rural Builder
Brave new world of the pole barn house
By Michael Momb for Rural Builder magazine
About a decade ago my bride took a phone call from a potential pole barn purchaser. The female caller identified herself and then said despairingly, “My husband wants me to live in a pole barn house…and I don’t want to live in a barn!”
The Momb’s dream home incorporates traditional gambrel style barn design with new post-frame construction.
Unfortunately the level of her panic told my wife this caller really had no clue as to what a pole building could “be”. My wife got off the phone, turned in her chair and stated to me “we need to build a barn.” Now I am more than happy to accommodate my lovely bride, but to have her suddenly declare she wanted to “build a barn” definitely got my attention.
As it turned out, she wanted to build a pole barn house. She wanted the traditional “barn style”, which is called a gambrel, and to finish it “just like a house”. To make a long story short – we did just that. The main part of the building is 48 x 60 feet with two 18 foot enclosed sheds. I dropped one of them back a bit from the front-end wall to create more of a residential “look” and make it more stylish.
Center of the downstairs houses vehicles, a huge hot tub, a vintage pickup and two huge boats. One of the side sheds is a deluxe office space, with custom cabinets and built-in desks.
Upstairs has a large bedroom and master bath walled off, with a circular stairway up to a loft for my wife’s sewing room. The living room is huge, with vaulted ceilings and room for a pool table, desk/office space plus a dining area. Both the bedroom and living room have gas fireplaces.
My wife calls her pole barn house her “home fit for a queen”. I do believe she just may be right!
I’ve noticed post frame building (the caller’s “pole barn”) becoming more popular over the past several years. Having personal experience, I can relay from the trenches.
The result of my wife’s conversation was we decided to use post frame construction to construct a building which could be used residentially. We also felt post frame offered advantages which no other form of construction could.
Here are the Good, the Bad and the Ugly of our over 8,000 square foot post-frame building:
- Even though I truly understand post-frame construction, I appreciate building departments which actually perform structural plan reviews and field inspections. Where this building is located, for the price of an average Domino’s Pizza order, one can obtain a building permit – with no inspections!
- We ordered triple glazed Low-E argon vinyl windows of various sizes, styles and dimensions, including a series of 10 which make an arch 24 feet wide and 12 feet tall. One of the selling points by the wholesaler was the lifetime warranty. Only after the windows began failing (including one which literally fell out of the vinyl) did I find the company had sold its vinyl line and my warranty was worthless.
- The HVAC system – it is also Good….until it needs to be serviced, as it is nearly impossible to find a contractor who is knowledgeable and will travel 90 miles south of Fargo.
- We had to get a variance because an accessory building in this particular jurisdiction was limited to a 10 foot eaves. My wife convinced them of just how impractical the limitation was, and they stamped her request as “approved”.
- At times building contractors tend to “go their own way” – and ours was no different. We ended up with stairs so steep they never would meet code, yet there would have been plenty of room for them to have been done right.
- The elevator. Yes, elevator. My wife told me she wasn’t going to hike up a 20 foot rise of stairs forever. The pneumatic elevator is a nifty idea, and it is fabulous when it runs. It does require some adjusting from time to time to keep it operating.
- The building is on an ideal site on a lot of over two acres. The land to the north is a State of South Dakota game refuge and to the south, one can see six miles up Lake Traverse to Browns Valley, Minn.
- The building uses geothermal wells as part of the HVAC system. A series of 275 foot deep wells are incorporated into it. Once past the sticker shock of the system, it is very cost effective. We were told it would take 24 hours to get the building up to temperature, however it is closer to four to six hours.
- Dale and Tom from Timber Technologies provided glu-laminated Titan Timbers as long as 50 feet in 4-ply 2 x 8 for the overall height of 44 feet above grade. After they were placed and concreted in we had some 60-mile per hour winds. The tops of the columns reminded me of watching the Tameracks near our Spokane, Wash., area home which bend in the wind, but never break.
- This building is gambrel (barn) style. The center portion has a 20-foot tall eaves, and is 48 feet wide. The roof pitch break is eight feet from each side horizontally and 16 feet vertically. The upper portion of the roof has a 6/12 roof slope. The center portion has clear span wood parallel chord floor trusses, which are 44 inches thick. From top of slab to ceiling in this 48 by 60 area is 16 feet. It was designed to be a one-half court basketball court. Above this are gambrel trusses with a 16 foot ceiling height – the inside slope of the gambrel is 12/12 which makes for some unique interior spaces.
- Truss fabricator WB Components and the engineers at Alpine Engineered Products were exceptional to work with. They never said no and always were looking for a better design solution.
- BIBS insulation is the bomb. I had used it in the walls of my garage shop in previous years. Besides affording a nice R-value, it fills all of the voids, making for a very quiet interior, even when the wind is howling outside.
- One of the keys to success is not in how we do the job right the first time, but how we take care of the mistakes. Each side of the gambrel portion of the building has an 18 foot wide side shed, with I-joist rafters. The rafters were ordered from the Home Depot in Fargo, who had a great price. The challenge: only after the builder had installed them did he realize they sent a smaller size than what was ordered and they needed to carry the load! Home Depot stepped up and provided enough additional I-joists to cut the spacing in half, at no additional charge!
A CLIENT’S EXPERIENCE
We have a client in Colorado who has been trying to get a permit to build since last fall. His building is similar to ours (a gambrel) with a smaller footprint of 2,880 square feet. Upstairs will be a 1,440 square foot living quarters. The downstairs is to be used strictly for the owner’s vehicles.
Should be easy, right?
I (as well as most of the post-frame industry) have had little direct involvement with residential post frame. Here the building official is giving me a free lesson:
“….. forwarded me your email to help explain to you what is going on with the barn with dwelling above as noted below in your email. The size/area of the overall structure kicks the entire structure into the 2012 IBC for review. As you know the R-3 fire area kicks the entire building into the sprinkler system requirements as noted in section 903.2.8 of the 2012 IBC. The character size/area and use of the barn/garage area within the structure lends itself to the S-2 classification except that it is private use and not commercial use.
Thus locally we have determined to leave such areas classified as Group U occupancies while having them meet the requirements of the S-2 occupancy. This being said, you need to look at footnote b of Table 508.4 in the 2012 IBC which states: The required separation from areas used only for private or pleasure vehicles shall be reduced by 1-hour but to not less than 1-hour.
Due to the possible mix of garage and barn type uses with these structures, the fuel loads in the unfortunate event of a fire can be extremely significant within the mixed barn/garage environment. Consider vehicles of varying types with fuel in their tanks, storage cans of fuel, paints, solvents of varying types, hay, straw, wood shavings or chips, etc… We would be well within the scope of the intent of the code to jump to an even higher hazard occupancy classification which would lead to not only a different type of sprinkler system but also maintaining a 2- to 3-hour separation between the occupancies within the structure. Locally we have decided to take the approach noted above in the first paragraph and allow the owners of such structures two options.
- Option 1 is to divide up the occupancy areas within the structure with a 2-hour Fire Wall (as described in section 706) such that in the eyes of the code, we have two separate structures. The dwelling area may then be constructed under the IRC instead of the IBC. If the barn or garage area with the dwelling area removed is still over 3,000 square feet it would still fall under the IBC for review and meet the requirements needed for that review. If the garage/barn area left over from subtracting out the dwelling area is less than 3,000 square feet, it too may be constructed under the 2012 IRC as an accessory structure. Again, once the true 2-hour Fire Wall exists the code will allow us to look at each one as a separate structure. The key here is it must be a true Fire Wall type separation and not a Fire Barrier. Considering horizontal firewall assemblies, there is some justification to make them 3-hour instead of 2-hour so that they serve their intended purpose in the best of ways. We have not gone to the 3-hour on horizontal firewall assemblies at this point.
- Option 2 is to fully sprinkle the structure and provide the “not less than 1-hour” fire separation between the occupancies concerned (see leading paragraph notes). The local Fire Department having jurisdiction would need to review the structure being sprinkled to decide which type of sprinkler system is needed for proper structure protection.“
Due to the versatility of post frame buildings, we will see some very complex structures, with entirely new challenges to be faced. It is a brave new world we are entering!