Tag Archives: concrete piers

Insulation Options for an Idaho Barndominium

Insulation Options for an Idaho Mountain Post Frame Barndominium

Loyal reader LORISTON in NAMPA writes:

“We are in the initial phase of preparing for our residential post frame home and are excited to partner with Hansen Buildings when ready. Thank you for all the amazing information and supporting your clients. Question: I am targeting a highly efficient design, with >r-40 walls and >r-60 roof. There is a lot that I do not know and humble to learn from others. My mechanical engineering background helps. I would like your advice on a wall and roof design that meets my targeted R-values incorporating (from outside to inside) metal siding, >3/4″ rain screen, rock wool >2″ external insulation, Zip insulated r sheathing for WRB and thermal break/R-value increase, laminated Timber Tech glulam columns with bookshelf / commercial girts, closed cell spray foam internal insulation around 3″ thickness, fill remaining thickness from spray foam to inside edge column with insulation (recommendation would be helpful on type of insulation), internal insulation on inside of wall for thermal break if needed or helps, with final residential area having 5/8″ sheetrock and shop area having metal inside finish. We have not solved how to create a space for utilities on the outside wall as we would prefer to run them on inside of columns or thermal break insulation. We are contemplating internal framed 2×4 walls spaced away from post frame wall to create a space for utilities. No water will be run on external walls, only power, low voltage, gas, telephone as reference. Suggestion on how to run utilities with this highly efficient wall design would be appreciated. Roof is similar to wall, just horizontal with >r-60 performance, as we are targeting a conditioned attic space. Roof exception may be a second zip sheathing layer over the insulation (under rain screen/standing seam metal) but to be determined. Climate Zone 6 region in the Idaho mountains for reference. Post frame columns and wall will be on a full foundation wall with thickness based on wall design. Performance is priority over cost, targeting an air tight and efficient living space. Your experience and practical approach are greatly appreciated. Best regards and thank you.”

Mike the Pole Barn Guru writes:

Thank you for your very kind words, they are greatly appreciated.

Rather than add an expensive and structurally unnecessary concrete foundation wall, I would recommend embedded properly pressure preservative treated wall columns (as my first choice), columns above grade set into wet set brackets on concrete piers as my second. Either of these can be insulated using R-10 EPS (Extruded Polystyrene) insulation boards. I would run them on the inside of the splash plank, with the top even with the top of the slab, extending down two feet, then outward horizontally two feet.

In Climate Zone 6, I normally would not look towards spray foam as my go to choice, however conditioning your attic and your desire for air tightness come into play, so here goes:

Walls (out-to-in): Steel siding over 2×8 bookshelf girts; 4″ of closed cell spray foam applied directly to inside of wall steel and balance of cavity with either open cell spray foam or rock wool (rock wool being my preference). No internal vapor barrier or continuous interior insulation boards as we want walls to dry to interior, without trapping moisture in the wall cavity.

Roof (out-to-in): Standing seam steel over 30# felt or synthetic ice & water shield (second preferred) over 5/8″ CDX plywood. Zip sheeting is OSB and screws just do not hold well into OSB. We can specify 2×12 roof purlins in order to get a deep cavity for insulation. Closed cell spray foam 5-3/4″ (R-40) plus R23 rock wool (5-1/2″).

This combination will require mechanical removal of humidity.

My normal recommendations would be:

Walls (out-to-in): Steel siding over a Weather Resistant Barrier, over 2×8 bookshelf girts. Fill the cavity with two layers of R15 rock wool. Add R-10 EPS well-sealed on interior. This wall will now dry to the outside.

Roof (out-to-in): Through screwed steel with an Integral Condensation Control factory applied, or standing seam steel over 30# felt or synthetic ice & water shield (second preferred) over 5/8″ CDX plywood. Roof trusses with 22″ raised heels, vent eave and ridge. Blow in R-60 on top of ceiling. This eliminates the expense of heating/cooling a dead attic space.

In either instance, I would have no fears or concerns about running non-plumbing utilities within your wall insulation cavity.

Will My Minnesota Shouse Require Frost Footings?

Will My Minnesota Shouse Require Frost Footings?

Reader CHAD in JANESVILLE writes:

“I am planning on building a shouse or barndominium some may call. I am doing 5″ cement with a heated floor throughout. My hope was not to bury any poles but to anchor them on top of the slap. Do you recommend front footings or will I be same as long as I am heated?”

My lovely bride and I happen to live in a post frame shouse just four hours West of you (and you are welcome to come for a visit)! In our instance, we used embedded columns, as I fully believe they will outlive my grandchildren’s grandchildren (for reading on lifespan of properly pressure preservative treated wood https://www.hansenpolebuildings.com/2020/09/pressure-treated-post-frame-building-poles-rot/).

Now we do have a fair number of clients using wet set brackets, keeping their building columns above ground (https://www.hansenpolebuildings.com/2019/05/sturdi-wall-plus-concrete-brackets/).

These brackets need to be either placed into a continuous footing and foundation system, a thickened edge slab on grade or concrete piers. Any of these should extend below frost line, unless provisions are made to thermally isolate them from effects of frost.

The U.S. Department of Housing and Urban Development Office of Policy Development and Research has been so kind as to publish a plethora of information on Frost-Protected Shallow Foundations, (while not specific to post frame construction) would apply to any structural building system. Heat transfer truly doesn’t care how you put a structure together, just so long as thermal resistance issues are taken care of adequately.

Those who are considering Frost-Protected Shallow Foundations should peruse this information: https://www.huduser.gov/publications/pdf/fpsfguide.pdf, and utilize it to determine requirements for insulation R values, as well as depth vertical insulation boards should be placed and width of horizontal insulation extending out from your building.

Whatever your choice is, you should have structural plans sealed by a Registered Professional Engineer to verify system adequacy.

Unheated Post Frame Building Slabs on Grade

Are Unheated Post Frame Building Slabs on Grade Required to Be Frost Protected?

Reader BILL in CLAYTON writes:

“I’m in early planning for a post frame garage – just over 1000 sf but will reduce it if it solves a code problem for “private garages” in IBC. Ignoring that, where does the code permit a slab on ground floor in a post frame building to not be frost protected? Is it not a part of the “building and structure”? Obviously, the floor in most unheated post frame buildings with slabs are not frost protected. In IRC (which Hansen says does not apply to post frame) R301.1 says “Buildings and structures, and parts thereof…” shall be on a foundation and R403.1.4.1 “Except where otherwise protected from frost, foundation walls, piers and other permanent supports of buildings and structures shall be protected from frost by one or more of the following methods:…:” Is a slab on ground floor excluded from “foundation walls, piers and other permanent supports of buildings and structures”? The slab on the ground floor is not a part of the building and structure? Thank you!”

IRC R301.1.3 Engineered design.

“When a building of otherwise conventional construction contains structural elements exceeding the limits of Section R301 or otherwise not conforming to this code, these elements shall be designed in accordance with accepted engineering practice. The extent of such design need only demonstrate compliance of nonconventional elements with other applicable provisions and shall be compatible with the performance of the conventional framed system. Engineered design in accordance with the International Building Code is permitted for all buildings and structures, and parts thereof, included in the scope of this code.”

Unless your site is precluded from having a detached accessory building of over 1000 square feet – my recommendation is to erect the largest building you can afford and fit on your property. Whatever size you build, it will not be large enough. Being over 1000 square feet just means you have an S-2 rather than U classification building and is not going to affect structural design unless your Building Official deems your structure to be Risk Category II, rather than I.

Foundations of most post frame buildings are either embedded columns or columns anchored by approved wet set brackets to concrete piers. A slab on grade, in a post frame building with foundation as described, has no weight of building placed upon it, therefore is not a permanent support of structure.

With this said, Jefferson County is in Climate Zone 6A. As such I personally would follow International Energy Code Table R402.1.2 and place R-10 rigid insulation inside of my splash plank from top of slab (3-1/2″ up from bottom of splash plank) extending downward 48 inches. This can easily be done by trenching at time of construction and would be of benefit should building ever be heated (as most strictly non-agricultural buildings usually are at some point) and be a point in eventual resale.

Busting Post Frame Barndominium Myths

Busting Post Frame Barndominium Myths

Yep, I have been web surfing again and I came across a stick frame building contractor’s website who obviously either doesn’t understand fully engineered post frame construction, or just frankly doesn’t care to add it to his arsenal of design solutions. My comments are in italics.

MYTH #1. MOST BANKS WON’T OFFER CONSTRUCTION LOANS ON POST FRAME POLE BARN HOUSES.
Many lenders refrain from offering traditional mortgages for pole barn homes. For example, Freddie Mac and Fannie Mae will not offer these loans at all.
The small percentage of entities that do offer mortgages for pole barn homes will typically have much higher requirements, because they’ll be using internal money to finance it.
They’ll likely require a 30% down payment (and oftentimes, more than this).

In reality, a fully engineered post frame building is no different than any other wood frame steel roofed and sided home and any lender will approve a mortgage for one as long as you do not use terms like “barndominium”, “pole barn house”, “post frame house”, etc. Apply the K-I-S-S method (Keep It Simple Stupid) and refer to it only as being a fully engineered, custom designed, wood frame home with steel roofing and siding. Period and 100% factual.

But won’t my lender send out engineers and inspectors who will “catch” me building a barndominium, shouse or post frame home? No. Your lender will be concerned about progress, not how you are getting there.

Before going to a lender you will need a place to build (land), blueprints (floor plans and elevations) and a budget (or contract subject to finance approval with a builder).

MYTH #2. THERE ARE NO FOOTERS IN POST FRAMES
Without having footers to protect the concrete slab from freezing, there is the potential that the concrete slab can move or heave around the edges in cold weather. In turn, this can shift interior walls, resulting in damage to drywall finishes and trim.
If you do go with post frame construction, you will have to add footers to stay in code compliance of the IRC. This will add that cost back into the total price of the home.

Your fully engineered post frame home is 100% Building Code Compliant and most typically has pressure preservative treated columns embedded in ground with both concrete footings and bottom collars. Alternatively your home can be mounted to steel brackets set in concrete piers.

Either of these are designed to extend to or below frost lines or are frost protected by use of insulation. Footers themselves do not protect a concrete slab from freezing and heaving, using rigid insulation around slab perimeters is required for either stick frame or post frame. With fully engineered post frame, there is no need to incorporate thickened slab edges or continuous concrete footings and foundations.

MYTH #3. POST FRAMES WILL HAVE LARGER SPANS IN THE ROOF TRUSSES
This is an issue because they’ll have to be filled in before you can hang the drywall.

If you hang drywall “as is,” it will all sag over time, causing structural damage (and a pain in your wallet). Adding this extra framing after the fact will add to the total price tag again.

Most cost effectively your fully engineered post frame building will have double trusses every 10 to 12 feet. If you desire to insulate at ceiling lines, ceiling joists are placed every two feet to adequately support drywall. This combination of double trusses and ceiling joists will still be less expensive than conventional stick framing’s trusses every two feet with structural headers required in walls. By widely spacing trusses, it allows for greater flexibility in locating doors and windows in exterior walls.

MYTH #4. EXTRA FRAMING BETWEEN THE POSTS WILL BE NEEDED
As opposed to traditional wall building, you’ll have to build the walls between the posts after you build on the post frames. This is an added cost to the post frame structure that has already been built.

We can tell this builder has never built (or probably seen) a fully engineered post frame building with bookshelf girts every two feet. All exterior wall framing is taken care of at initial installation, you get a deeper insulation cavity and a better surface to drywall. https://www.hansenpolebuildings.com/2019/09/11-reasons-post-frame-commercial-girted-walls-are-best-for-drywall/

MYTH #5. INSULATION COSTS ARE HIGHER
Your pole barn home will require more insulation on a post frame wall because the walls are thicker than the typical two-by-four construction. Therefore, the cost of insulation will be higher to fill this cavity.

Would you really want an electric bill based off of R-13 insulation in a two-by-four exterior wall? Engineered post frame construction allows for thicker insulation cavities – reducing your energy costs for your barndominium’s lifespan.

MYTH #6. POST FRAME CONSTRUCTION IS TYPICALLY NOT USED WITH BASEMENTS.
Post frame construction is not very conducive when building on a basement, as the basement walls will be made from poured concrete. Trying to adapt a post frame construction to a basement will end up with higher costs than traditional home building techniques. The bottom line: If you want a home with a basement, post frame construction is not the best choice.

Your fully engineered post frame home can easily be engineered to attach to a concrete basement foundation, ICFs or even incorporated into a Permanent Wood Foundation, at similar or lower costs than stick frame.

Concrete Piers, RV Carport, a Wedding Venue

This week the Pole Barn Guru answers questions about building with concrete piers, design of storage for an RV, and how wide a venue for weddings can be built.

DEAR POLE BARN GURU: I will start with the biggest question I have.
Can you design a Pole Barn building 40x60x14 Gable roof 5/12 to be on 10ft ground clearance concrete piers? Do your kits include subfloor for such as I described?
Please see attached picture as an example to Building.
We must be able to meet a 140mph hurricane rating.

I would really like your opinion on my question as you have given lots of good advice to others. RUSSELL in DEVERS

DEAR RUSSELL: Thank you for sending a photo.

I can only interpret your concrete piers as telling us you want to have your living area 10 feet above grade – a stilt house. If we are talking same language then yes, building could be mounted to concrete piers, however it would be far more economical to use properly pressure preservative treated wood columns. If you were to opt to go with concrete piers, our third party engineers could design them, and their attachment, however this would need to be contracted directly with our engineers by you. Wood column design would be included with your engineered building plans if wood columns were used.

Our building kit packages include all structural members needed to enclose your building, so you would have a floor system and 3/4″ sheathing .

We have provided buildings with up to 170 mph design wind speeds with Exposure D.

 

DEAR POLE BARN GURU: Any ideas on how to value engineer this down? I’ve streamlined the layout of the house as simply as I can, any other suggestions?

Maybe make garage and RV shed a carport like instead of totally enclosed? Maybe no concrete floor, instead gravel floor? Suggest anything.

Trying to get a price on this now locally, but difficult to get replies.

Can you pass along and get a quote from Hansen? GINGER in STARKSVILLE

DEAR GINGER: Your interest in a new Hansen Pole Building is appreciated. As I have not been privy to your discussions with your Building Designer, Tom and have not seen your floor plan, I can’t really speak to it.

With a 16 foot eave height, your building is not tall enough for two floors, so I would suggest stepping down the roof line in your home.

Tom will be reaching out to you shortly.

 

DEAR POLE BARN GURU: Wanting to design a wedding venue, main area 40′ x 90′, with 15′ lean to’s. What is the maximum span for a pole barn with a loft. Trying not to have any support poles in the middle of barn. MIKE in VIRGINIA BEACH

DEAR MIKE: Our own post frame shouse (shop/house) happens to have a 48 foot clearspan floor and we could have gone to 60. Some of your clearspan ability will be based upon your use of this second floor. Keep in mind, if this is to be an area with general public use or staff, you will need to provide handicap accessibility (an elevator) to it.

 

 

 

Yet Another Case for Engineered Buildings

Yet Another Case for Engineered Buildings

(The six photos at https://www.hudsonvalley360.com/article/construction-resumes-following-barn-collapse are essential to this story)

In case you are wondering why I rail so loudly about building permit agricultural exemptions for buildings, these photos (look at bases of columns) should quell any wonderment. https://www.hansenpolebuildings.com/2011/12/exempt-agricultural-buildings/

From a September 2, 2019 article by Amanda Purcell at www.thedailymail.net  of Gallatin, NY:

“Construction will resume on a farm on Green Acres Road after the barn collapsed and injured a contractor two weeks ago.

A stop-work order was issued for Red Hook-based Bijou Contracting immediately after a barn collapse injured a contractor at 138 Green Acres Road on Aug. 16, according to documents obtained from the town.

A worker suffered non-life-threatening injuries and had to be airlifted to Albany Medical Center after he became trapped under the debris, New York State Police Sgt. Michael Comerford said Aug. 16.

Emergency crews were called to the scene at 9:55 a.m. The contractor, a man, was extricated from the debris by Northern Dutchess Paramedics before firefighters arrived on the scene, Livingston Fire Department Public Information Officer Dana Petty said.

Comerford declined to identify the man or state the extent and nature of his injuries out of concern for violating the Health Insurance Portability and Accountability Act.

Building Inspector and Zoning Code Enforcement Officer Jake Exline declined to comment on the incident, investigation or what might have caused the collapse, but documents obtained via a Freedom of Information Law request showed a stop-work order was issued to Bijou Contracting the same day as the collapse.

The underlying 7,200 square-foot barn structure was mostly complete at the time of the collapse, according to photos. Photos obtained via Freedom of Information Law request show debris toppled over two scissor lifts. Photos show cement footings were released from shallow halls as a result of the collapse.

“Any and all work is to be stopped pertaining to the construction of permitted pole barn,” according to the notice signed by the zoning officer Aug. 16. “All debris is to be cleaned up and removed from the property. All construction equipment used during the construction process is to be stood back up, and removed. Once the site is clean, we can have a meeting to discuss going forward.”

The building permit was not revoked by the town, and work is expected to continue after all the materials are cleared from the site. As an agriculture building, the structure’s plans were not subject to review by the Gallatin Town Planning Board.

The building permit for the 48-foot-by-150-foot pole barn on the 89-acre farm was issued July 2 by the town to property owner Alex Fridlyard. The project was estimated to cost $70,000.”

If a picture is worth a thousand words, then those of this building’s woeful inadequate concrete piers and mounting brackets speak volumes. With an engineered building, those concrete piers would probably have been two foot or more in diameter, four feet deep (to meet frostline requirements in this area) and columns would have been mounted to engineered brackets adequate to resist imparted forces. Hopefully someone learned from this experience. However my fear is history will be sadly repeated.

Don’t let a situation like this become your mistake – for a fully engineered post frame building call us (866)200-9657