Today the Pole Barn Guru answers reader questions about moisture control, insulating a building with a ridge vent, and a solution for replacing posts that have rotted out.
DEAR POLE BARN GURU: Thanks for the abundance of technical information you provide your readers. Like many of them, I inherited a pole barn with the same ceiling sweating, heat, cold issues and need a post construction solution. The slab sweats only in some places. I have a typical wood post with 2×4 horizontal purlins, wood truss and purlin roof, and metal skin walls and roof. My goals are, #1 stop the moisture inside, #2 insulate for moderate comfort (no codes to comply with and I can heat with a wood stove and abundance of wood) , and #3 if I can afford it, skin the walls with T-111 or other wood for an attractive look inside. I did not see any suggestions about double-faced radiant barriers in your other articles. Do you think expanded polystyrene cut to fit in the 1.5 inch cavities to flush with purlins, and then add the radiant barrier (bubble type) stapled over that directly to purlins would be appropriate and not trap moisture? If so, should I allow and air space between the polystyrene and radiant barrier? Many thanks, Mr. Retired…finally! JOHN in CHEROKEE VILLAGE
DEAR JOHN: Thank you for your kind words. If your slab sweats at all, it is likely there is no vapor barrier under it and it would behoove you to apply a sealant. 1.5″ expanded polystyrene (EPS) boards cut to fit tightly and with all seams tightly sealed would give you some degree of insulation (roughly R-7.5 other than at girt and purlin locations). You could add unfaced rock wool batts to increase insulation. Radiant barriers provide next to no insulation value and only function if seams can be perfectly sealed, we’ve actually opted to no longer offer them to our clients.
Unless you want to heat area in triangle of trusses, you may want to consider insulating at ceiling level, then vent dead attic space above.
DEAR POLE BARN GURU: Hello Mike. I came across your website while trying to learn more about what to do with the ridge vents in a pole barn when you plan on insulating it with closed cell foam. My wife and I purchased a property that has a 36w x 48L unconditioned pole barn with 8 skylights, a couple of ridge vents and (2) sets of huge doors on each end. While we know this will never be a tight building, we need to insulate it for our pets (10) dogs and (11) cats, and for a hangout area for us to spend time with them rather than inside our home.
We have a high-end American Standard heat pump split system that will condition the entire space.
Would you be able to give me any advice on what you recommend I do regarding the existing ridge vents? I’m not sure if I should insulate around them and leave them as they are…open. Or, should I temporarily trim out around them and seal them for the time being?
Any information you could provide me on this topic would be greatly appreciated. ROGER in HOUSTON
DEAR ROGER: With those large sliding doors, your investing in closed cell spray foam may be for naught. If your expectation is to be able to control any sort of heat loss/gain you should consider replacing them with insulated steel sectional overhead doors.
On to your question – seal off ridge vents and spray foam across skylights (or, even better) replace them with steel roofing before insulating.
DEAR POLE BARN GURU: What are my options on repairing 32×40 all 6×6 posts are rotted off ground level. Floating slab, perma colum, helical peir, or strongway sleeve. CHAD in GREAT BEND
DEAR CHAD: I would repair one column at a time. Temporarily support roof system being supported by a column. Cut column off above point of decay. Excavate embedded portion of column and remove – hole being dug to be at least below frost line. Insure bottom of hole is firmly compacted. Place a sonotube in hole, attach an ICC approved wet set bracket to bottom of column and backfill with premix concrete. Compact granulated fill around sonotube in six inch lifts. Repeat at each column.
DEAR POLE BARN GURU: As a prospective customer, doing as much research and educating myself your site and information has been a wonderful tool. Through my educational journey the most confusing area is with post construction being set in concrete. Your blog has answered many questions and worked to dispel myths about rotting wood. But, there is a product or system (Perma Column Cast Concrete pole bottoms) that seems to be the ticket to eliminate any concern about rot, Valid or not. What are your thoughts on this approach? Any insights are very much appreciated. BRIAN in POULSBO 
DEAR POLE BARN GURU: Are any of your barndominiums classified as a single family dwellings? JOHN in EAST CANTON 
DEAR DANIEL: Your premature decay of fence posts has nothing to do with how fast lumber grows – it is them not being pressure preservative treated to UC-4B levels. All of our fully engineered post frame (pole barn) buildings utilize this level of pressure treating and it performs admirably. If you are yet concerned, there are options available such as plastic column sleeves, or pouring piers with wet set brackets to keep columns out of ground entirely.
DEAR POLE BARN GURU: Concerning fastening house wrap, can you use button staples as recommended by house wrap companies? I didn’t know if the button would show through the tin. I don’t want to lose house wrap before tin would be up as we live in a very unpredictable and windy area but also don’t want button to show through tin if that’s a possibility. Thanks! ADAM in COLBY
DEAR POLE BARN GURU: Hello, I am building a pole barn for cattle in the north TX area ( primarily clay soil). I have augured my post holes and took a lot of time making sure I set the post square and plum. Unfortunately before the concrete truck couldn’t get to me the rain started and dint not stop. All of my post holes stayed full of water for about 1.5 weeks…. Since then I have pumped them out and we have had 2 weeks of high 90 degree days with full sun but the bottom of the holes are still muddy. My plan has been to let them dry out but I wonder if I need to pull the post, possibly auger out the mud and repack them. This option of starting all over gives me heart burn!!! My concern is that my post will sink and settle when I add the weight of concrete and all of the other building materials. I know you probably can’t say definitively but if you were in my shoes would you start all over or do you think it would be ok to just let them dry out and move on? Not sure if it matters but the post holes are 16″ in diameter and 52″ deep. Thanks for any advice! ANTHONY in SHERMAN 
DEAR POLE BARN GURU: Do you provide quotes for a Maintenance Garage in Salem, Missouri? DANIEL in ST. LOUIS 
DEAR POLE BARN GURU: My GF lives in In Indonesia and as you know, they are moving the Capitol. Because of rising water levels. I saw some rubber ” boots” that are supposed to protect against rot from water. They also sell concrete for building a ” pier”. Any advice? She has family there and does not want to leave. MATHEW in RENO 
DEAR MATT: In my humble opinion, this could be resolved by having clear markings on Pressure Preservative Treated wood to not leave any doubt as to what proper use is. I have stomped my feet on this very issue for years: 
DEAR JEFF: Assuming standard post frame building construction where top of concrete slab is 3-1/2″ above bottom of pressure preservative treated splash plank. From bottom of splash plank to bottom of sliding door header would need to be 13′ 4-3/4″ to allow for a 13 foot tall sliding door.
DEAR POLE BARN GURU: Hey I found you thru Hansen Buildings and had a question you might be able to answer just built a 24 x 16 pole barn and on the left and right added sheds but only half the building length what do I do with my gable trim that ends in the eave on the roof side of it just don’t know how to end it? JEREMY in SILETZ
DEAR POLE BARN GURU: 
DEAR POLE BARN GURU: We are in an area of 120 – 150 snow load in the mountains of MT and want to error on the 150 load side when building our shed. The shed plan is 30×70 (2 RV doors) on the 30 side) with a 15×70 enclosed lean to (car garage door on the 15 side) that will have a car garage, workshop and storage room. Can we do a pole building with this size of shed and snow load or do we have to go stick built? KIM in BIGFORK
DEAR POLE BARN GURU: 
Thanks. GREGG (a Hansen Pole Buildings’ Designer)
DEAR JASON: If yours is typical post frame (pole) building construction, your opening probably measures 12 feet from center of column to center of column, in which case you would be looking at needing a 12 foot width split sliding door. This would give you two door leafs just over six feet in width, enough to cover the opening, provide an overlap on each side and be able to be covered with two three foot widths of steel siding.
DEAR ABE: Do not use this insulation as you have intended, it will cause you nothing but grief. Not only will your post frame barn roof leak, but the diaphragm strength of your roof steel will be severely compromised, which could lead to a catastrophic failure. Tyvek and other building wraps are not condensation control barriers, they are moisture barriers. There are several possibilities – invest in roof steel with Condenstop or Dripstop preapplied, use a radiant reflective barrier between the purlins and roofing, or spray closed cell foam on after the roof is installed.
