Tag Archives: stick frame building

Why Your New Barndominium Should Be Post Frame

Why Your New Barndominium Should Be Post Frame

For those who follow me – you know I am all about people loving their end results. As long as one has a fully engineered building they love, I couldn’t be more pleased, regardless of the structural system.

In My Humble Opinion – fully engineered post frame buildings are your best design solution in nearly every case. My exception would be if one desires a clearspan over 80′ or a very low slope roof – then I would recommend PEMB (red iron).

PEMBs do have some of their own unique challenges – a foundation engineer must be hired, they take lots of concrete and foundation bolts must be precision placed, Requires heavy lifting equipment to erect, when shell is done – have to frame a house inside. Thermal bridging is a concern and how does one hide those big steel frames?

But, what about stick frame?

Perhaps stick built construction’s biggest advantage is builders and tradespeople are very comfortable working in and around stick framing. All registered architects and most building inspectors are very familiar with stick framing. International Residential Code (IRC) provides a prescriptive ‘cook book’ to follow for adequate structural assembly, within certain limitations. These limitations include, but are not limited to, no story height of greater than 11 feet 7 inches (R301.3), no hurricane prone areas with a design wind speed of 130 mph or greater located south of Virginia, or 140 mph elsewhere (R301.2(5)B), and no ground snow loads over 70 psf (R301.2.3).

IRC802.10.2.1 further limits truss spans to a maximum of 36 feet and building lengths to 60 feet (measured perpendicular to truss span). Trussed roof slopes must be at least 3:12 and no greater than 12:12.

Want a 40’ x 72’ x 14’ shop/house barndominium? Sorry, outside of what IRC allows.

And because IRC tables cover up to a worst case scenario (given maximum design parameters), it creates overkill, wastefulness and redundant framing members. Translated to – it takes more pieces than might be necessary in a fully engineered structural system.

Fully engineered post frame buildings include foundation plans, PEMBs require one to hire another engineer to provide foundation design. Plan upon a grand or more just for PEMB foundation engineering and this can quickly escalate should a Geotechnical Engineer need to perform soils testing.

Post frame does not require precision placed anchor bolts, and requires no use of cutting torches or welding.

Post frame requires minimal concrete to resist settling, overturning and uplift. Any slabs on grade do not need to be thickened or have continuous footings/foundations.

Post frame can be erected D-I-Y without a need for heavy equipment (although I do appreciate a skid steer with an auger to dig holes). Any physically able bodied person, who can and will read step-by-step instructions can successfully erect their own beautiful post frame building.

Post frame has no highly conductive steel frames to thermally isolate and attempt to conceal.

Post frame is easily adaptable to more complex rooflines, and can be done in any combination of alphabet letter shapes. Fully engineered post frame can easily be erected over crawl spaces as well as full, partial or walkout basements.

When properly designed (with bookshelf wall girts), exterior walls are ready for wiring, insulation and interior finishes – no need to frame a home inside of a building shell.

Post frame provides deep wall insulation cavities and with raised heel trusses, any depth of attic insulation can be blown in above a finished ceiling.

Post frame can readily be done multi-story, with up to 40′ sidewalls and three stories (or 50′ and four stories with fire suppression sprinklers).

What Makes Some Buildings Better Than Others

I answer literally hundreds of building related questions every day. These questions come from many different sources – our staff, drafts people, engineers, architects, building officials, clients, builders and social media (just to name a few).

This question, posted in a Facebook group, is an exceptional one and I felt it necessary to share:

Pole Barn Guru Blog“What makes some buildings better than others? And at what point does it not matter? (Ex: building A frames with 2x4s. Building B uses 2x6s and building C uses 2x12s obviously B is better than A but C is overkill) Does the metal come down just to the thickness of it? Thicker is probably better but to what end? I’m talking straight materials not warranty or service of a company. Thank you.”

This answer actually has a remarkably simple answer. It all comes down to what loads a building is engineered for.

Period.

Not what some under educated person says makes it better, but what a highly trained Registered Professional Engineer is willing to stake their career upon by putting their name and seal on a set of plans.

You want a stronger building (whether post frame, weld up, PEMB, stick frame, etc.) then increase snow and/or wind design loads. 

It is seriously just this simple.

It does no good to have super thick siding and roofing, if the supporting frame is not able to carry equivalent loads.

I once had a client who was “concerned about snow loads” so wanted 2×8 roof purlins (when 2×6 would easily have carried the loads). I asked him what was going to hold those purlins up (a sky hook maybe) when his building’s trusses failed beneath them.

A building is a complete system.

When you hear a supplier or builder talking about how their bigger/stronger/thicker whatever makes their building best, think B.S., because they do not have a clue about structural design.

When you find the rare gem who advises you they are providing a fully engineered building and recommends above Code required minimum loads – stick to them like super glue, as this is truly a better design solution.

Here is just one example of when bigger isn’t always better: https://www.hansenpolebuildings.com/2014/08/lumber-bending/

I hired my first staff engineer roughly 35 years ago, Jenny Wong.  Jenny’s previous experience was as a design engineer for a nuclear power plant (seriously). Jenny knew absolutely nothing about post frame buildings, but was willing to totally trust me – provided I could find documentable proof from reliable sources. This one requirement alone shaped my professional career.

Ask me any post frame building questions, any time. If I cannot get you an answer, I will let you know. My answers will always be based upon factual evidence. If you find some method or component with an ability to make buildings better, without unduly penalizing new building owners financially please share it with me – I will perform due diligence to prove or disprove it and if it is truly beneficial, expect to see it in your next Hansen Pole Building.

Maximizing Sliding Door Heights

While post frame construction (in my humble opinion) gives the most value for construction dollars invested, there are just some cases where clients just are not aware. This reader wants to maximize the height of a sliding door opening on a stick frame building.

HOWARD in COEUR d’ALENE writes:

“Greetings, I am stick-building my own shop and would like to maximize the height of the door opening. I plan to have a load-bearing truss on the gable end to eliminate the need for a header. But if I use sliding barn doors such as you do on your buildings, will I still need a header for the door tracks? Could I gain more height by having the “header” designed into that end truss?

Thank you”

Dear Howard;

Just a heads up – if your shop is going to have a wall height of greater than 10 feet it is beyond the scope of the prescriptive portions of the Building Code and engineering will be required. You may want to consider post frame construction as it will be more affordable and easier to construct.

Moving forward…..sliding doors require a header, most usually 2×8, with a 2×6 track board mounted on the face to attach the track brackets to.

If you are using vertical steel siding, you will have to place 2×4 horizontally on the face of the studs to attach the siding. If this is your case, you can attach the 2×8 header to the face of the bottom chord of the end truss. Bottom of header and bottom of bottom chord can be at the same point. The limitation is you cannot run the door or the door opening within a couple of feet of the corner without it hitting either the end overhang (which I hope you have) or the rake trim.

With other sidings, the end truss can be held back 1-1/2 inches from the face of the stud wall. Add the 2×8 header across the face of the truss (as above) and then nail a 2×4 flat to the face of the end truss top chord to bring it out to flush. If using wood siding, you would need to add 2×4 vertical studs to the end truss face as well.

These solutions will allow for the clear height going through the door to be at the ceiling height of your building.

Mike the Pole Barn Gur