Reader KIMBERLY in LINDEN writes:
“We are building a 52x40x10 post frame home in East Texas. The entire thing will be living space. I have been researching as much as possible on the best way to insulate a post frame home with metal siding and roof. The information is overwhelming and you get a completely different answer depending on who you talk to. I know not to skimp on insulation, but the consensus on most “barndominium” FaceBook groups is that spray foam is the only way to go. I have reservations about that, because it may be a superior way to insulate, but it depends almost exclusively on who is doing the actual foam application. On top of that you need to spend more money on your HVAC system to add the proper ventilation/air exchange.
I want a well insulated home that is specific to the type of building material and location we live in. To me, “not skimping” on insulation doesn’t mean that it has to be the most expensive insulation either.
I also know the insulation world is constantly changing and evolving, but what would your recommendation be to insulate our home in East Texas?
Thank you so much for your time!”
Mike the Pole Barn Guru responds:
Your insulation requirements will vary depending upon where you are in East Texas. Climates zone 1 (closest to Gulf) require R-30 ceilings, R-13 walls. Zone 2 requires ceilings to be R-49 and zone 3 (farthest north) goes to R-20 walls. You can look up you county’s climate zone here: https://codes.iccsafe.org/content/IECC2021P1/chapter-3-re-general-requirements#IECC2021P1_RE_Ch03_SecR301. I will cheat for you and tell you Cass County is Climate zone 3A.
For sake of discussion we will assume you have a dead attic space and will be insulating directly above a finished ceiling. I would ventilate your dead attic space at the eave (air intake) and the ridge (air exhaust). Make provisions for preventing condensation on the underside of roof steel by having some sort of a thermal break. My personal preference is by using an Integral Condensation Control (https://www.hansenpolebuildings.com/2020/09/integral-condensation-control-2/). You will want to order roof trusses with raised heels (https://www.hansenpolebuildings.com/2012/07/raised-heel-trusses/), so you can get full insulation depth from wall-to-wall with blown in fiberglass. Heel height should be R value of insulation divided by three and add two inches so you can achieve adequate airflow above insulation.
Should you want to condition your attic – delete ventilation, raised heels and the Integral Condensation Control. I would apply closed cell spray foam two inches to the underside of roof steel, then add open cell spray foam to desired R value.
For walls – best results will be from two inches of closed cell sprayed to inside of wall steel, then fill balance of wall cavity with either open cell spray foam, or unfaced batts (ideally stone wool https://www.hansenpolebuildings.com/2013/03/roxul-insulation/). You could also use BIBs to fill (https://www.hansenpolebuildings.com/2011/11/bibs/). Do not place a Weather Resistant Barrier (WRB) under wall steel or a vapor barrier on inside of wall.
As an alternative to spray foam, you can use a WRB between framing and wall steel, then BIBs with an interior vapor barrier or faced batt insulation.
Energy costs are not going to go down, so I would encourage you to err towards more insulation rather than less – and (since most heat loss is upward) invest more into added ceiling insulation than walls.
In warmer, humid climates like yours, your HVAC system should include an Energy Recovery Ventilator (ERV) regardless of what your choice of insulation systems ends up being.
Without a well-sealed high qualify Weather Resistant Barrier (building wrap) between framing and siding, humidity inside wall will follow along with exterior relative humidity to a large extent.
Nice to see jurisdictions enforcing IECC (International Energy Conservation Code) requirements, as it will result in more energy efficient structures. In Ouray County, you are in Climate Zone 6B. This requires ceiling R-49, wood frame walls of R-20 plus R-5 (or R-13 plus R-10) where second value is continuous insulation and slab edges to have R-10 four feet deep.
Using two inches of closed cell spray foam directly inside steel siding panels not only air seals exterior walls, as it is an effective vapor barrier, but also provides approximately a R-14 level of insulation. Effective applications also require installing form fitted inside closure strips at top and bottom of every wall steel panel – including window and door openings. Closure strips keep spray foam in your walls rather than oozing out and keeps small crawling and flying critters out.
When placing under slab vapor barriers, run up inside of pressure preservative treated splash planks and sealing to top and around columns. Install seal gasket under pressure treated base plate (mud sill) and caulk inside edge to concrete slab.

DEAR KURT: Thank you for your investment in a new Hansen Pole Building – be sure to send me lots of progress photos during construction (and of course ones when it is all complete).
DEAR GREG: Any possible movement would come from either inadequately compacted or loose soil below column footings, inadequate footing diameter, or frost heave. To prevent frost heave, columns footings should be placed at frost depth or deeper and perimeter of slab should be insulated vertically with rigid insulation. In your climate zone, this would entail a four foot ‘tall’ R-10 insulation board. Install on inside face of pressure preservative treated splash plank, with top of insulation even with top of concrete slab. As an alternative, you can insulate slab perimeter per Frost-Protected Shallow Foundation requirements found here (note, slab edge does not have to be thickened or have a stem wall):
DEAR POLE BARN GURU: Hello Guru! We were wondering if the USDA Rural Development program allows for the construction of a pole barn home? KIRSTYN in LANSDALE
Engineered post frame (pole barn) houses rely upon their skin (usually steel roofing and siding) being properly installed to provide diaphragms. When material is placed between horizontal wall girts and steel siding to create a vented rain screen assembly, it defeats your building’s structural integrity, unless structural sheathing is applied to wall girts.
For walls – best results will be from two inches of closed cell sprayed to inside of wall steel, then fill balance of wall cavity with either open cell spray foam, or unfaced batts (ideally stone wool
DEAR TIM: Back in my post frame building contractor days we built many a building in and around Medical Lake.
DEAR ANA MARIA: Well, you have reached out to where you should be, as Hansen Pole Buildings specializes in post frame homes (barndominiums and shouses).
My recommendation would be to place a well-sealed WRB (Weather Resistant Barrier) between all wall framing and siding. Use commercial style bookshelf girts to create an insulation cavity
Thank you very much for your kind words. My goal is to see to it people avoid making crucial mistakes so they end up with buildings best meeting their wants and needs, and be as ideal as possible – even if they are not Hansen Pole Buildings.
This myth is created and propagated by post frame kit suppliers and post frame builders who do not understand there is a solution – and a very cost effective one (in both labor and materials).


DEAR JOSEPH: From Hansen Pole Buildings’ Construction Manual, Chapter 2:
DEAR PAUL: I am guessing you are talking about concrete poured for a footing pad under the columns. 
The purpose of a vapor barrier is to stop warm, moist, indoor air from infiltrating fiber-type insulation (think fiberglass or cellulose) during cold weather and condensing. Visible moisture or frost on the inside of a vapor barrier is either caused by a leaky vapor barrier or moisture migrating into the wall cavity from the outside. Leaky siding can cause this, and it often happens in basements that are apparently leak free. Vapor barriers are essential for any kind of insulation that air can pass through. Never do the really foolish act of slashing a vapor barrier that you find has moisture behind it or forgetting to install a vapor barrier in the first place. Today’s best vapor barriers prevent moisture from moving into wall cavities while also letting trapped moisture escape.
Once a ceiling has been installed, blow in attic insulation.