Tag Archives: UC-4B pressurem Preservative Treated columns

Rain Country, A High Water Table, and Door Options

This week the Pole Barn Guru answers reader questions about any added features for “rain country” like western Washington, use of UC-4B pressure preservative treated columns in a high water table area, and the options of a sliding door vs a sectional overhead door in an RV storage building.

DEAR POLE BARN GURU: Do many people build Hansen barndos in western Washington rain country and if so what added features. Are to be considered in heavy rain areas. DALE in WEST RICHLAND

DEAR DALE: Thank you for your interest in a new Hansen Pole Building. We have provided over 1000 fully engineered post frame buildings to our clients in Washington State, more than any other state!

There are some keys to success when building in any wet/damp climate.

Good site preparation is foremost. You want to have your concrete slab on grade to be poured on top of six to 12 inches of a properly compacted sub base, then add another two to six inches of sand or sandy gravel, before placing vapor barrier and any under slab insulation.

Building footprint should have a finished grade high enough to allow surrounding ground to be finish graded to slope away from building at no less than a 5% grade for 10 feet.

Building should have eave overhangs (12 to 24 inches) with gutters. Gutters should have drain exits at least 10 feet away from building.

Place a well-sealed Weather Resistant Barrier between wall girts and siding.


DEAR POLE BARN GURU: Going to build 2 pole barns on my property in Wewahitchka Florida about 15 miles from Mexico Beach. Water table on property is high and in a three foot post hole the water will seep and maintain 2 foot of water. Besides having a potential of hurricane winds what do you feel is best to withstand the water and winds over time for the supporting posts? Some I have read say wet set anchors are a pivot point not good for hurricane situations? Some posts in the ground not to weaken the post when blown by hurricane winds. Please inform best way and I am putting in for a quote from your company. ED in WEWAHITCHKA

DEAR ED: Embedded columns will be far more resistant to wind loads than bracket mounts.

If it was my own building(s), I would build up my site with compactable fill about two feet (compacted no less than every six inches) then sloped away from building no less than 5% for 10 feet or more. I’d then use columns embedded in ground.


DEAR POLE BARN GURU: I am exploring options for a garage for my 33ft 5th wheel RV. My RV is 12.5 ft tall, so looking at a 14 ft high door opening. Door Width will be 12 ft total. I’m looking at dual external sliding doors vs. a large and expensive rollup door. Is there a way to seal or insulate a sliding door setup? The only sliding door setups I am familiar with leave gaps at the sides, bottom, top. I have not decided if I will go metal kit, pole barn, or a traditional 2×4 and truss method for the structure. Thanks ROB in HERNDON

RV Storage BuildingDEAR ROB: After roughly 20,000 buildings, I have yet to have any client wish they would have installed sliding doors, rather than sectional steel overhead doors.

Your downsides of sliding doors are many. They will only seal tight enough to allow your neighbor’s cat to get in (not to mention the mice being chased by said cat). They cannot be effectively insulated. While electric openers are available, they are not for those who are faint of pocket book (read more about electric sliding door openers here: https://www.hansenpolebuildings.com/2017/04/propel-electric-door-openers/).

Most importantly, sliding doors are not wind load rated. This can become highly problematic. https://www.hansenpolebuildings.com/2014/12/wind-load-rated-garage-doors/



To Wrap Posts, Two-Story, Barndominium Conversion

In this Wednesday’s Ask the Guru, Mike answers reader questions about the use of bituthene to wrap the bottom of posts in addition to the treatment, the possibility of a two-story post frame building, and if one can convert an existing Hansen Building into a “barndominium” (residential unit).

DEAR POLE BARN GURU: Hi Mike, getting ready to build a pole barn and I have some bituthene I’ve been saving. The bottom of the posts are treated but I was going to wrap them in the bituthene as well to protect. Obviously this could potentially trap moisture in the post as well creating more problems than it solves. As long as the posts are dry do you see a problem with wrapping them? Thanks! TRAVIS in ELIZABETH

DEAR TRAVIS: Properly pressure preservative treated columns (UC-4B rated) should last in ground for your grandchildren’s grandchildren to be able to enjoy this building. Provided columns are dry (and kept dry during construction), wrapping them with a complete seal should not negatively impact their performance.


DEAR POLE BARN GURU: Do you have an two story options? I’m looking for a two-story barn kit that is approximately 40×60. Thanks. KRISTIN in JENISON

DEAR KRISTIN: We have provided a plethora of two-story buildings to our clients all across America. (Photos of a few of them are available here: https://www.hansenpolebuildings.com/gallery/homes/). We can provide up to three stories and 40 foot sidewalls (or four stories and 50 foot sidewalls with fire suppression sprinklers)


DEAR POLE BARN GURU: Good morning. I have a question about the project-11-1106. I now own this property and have two questions below.
1. Is this barn eligible for barndominium conversion? If so, do you have architects/engineers that you can recommend in the area?
2. If it stays as a barn, I’m planning to insulate it will Rockwool R23 comfortbatt. Do you have any recommendations how to properly get this done without causing any issues with moisture and I structure?
Thank you for making this “ask the guru” available. I will appreciate any guidance you can provide since you are more familiar with the structure of this barn/r, AMIE in OAK HARBOR

DEAR AMIE: Thank you for reaching out and for your kind words. This particular building was engineered to 2009 IBC requirements as a low-risk structure. In order to convert to a barndominium, it would need to be assessed and engineered to 2018 IRC with Washington State Amendments. If submission is on or after March 15, 2024 then 2021 Code would apply. We could work with this building’s original E.O.R. (Engineer of Record) in order to make this happen, however it may not be cost effective due to possible needed repairs to reach upgrade requirements. This would need to be done on a time basis, with an upfront nonrefundable retainer, as a fair amount of analysis will need to be done, as well as drafting and engineering costs.

In any case, adding of insulation and appropriate vapor barriers of any sort could result in excess humidity concerns and you should entertain involving an experienced HVAC provider to discuss mechanical dehumidification.

Trying to Add a Carport on a Social Security Budget Reader

Trying to Add a Carport on a Social Security Budget

Reader BRIAN in WHITE CLOUD writes: “I am planning (hopefully as funds exists) a free standing 24 x 24 x 8 sidewall carport that will butt up to the front of our existing garage. I am planning to use 6×6 treated posts sunk to 48″ deep on a pad. I will also place (2) 1/2″ x 12″ long re-rod through the bottom of each post and add 2 or 3 bags of redi-mix around the bottom of each post. Spacing at 8′ on center with an engineered 24′ 4/12 truss notched into each post with a double 2×10 header notched into each post around the periphery of the building. 2×4 purlins on edge with steel roof. My question is 1. Does this sound structurally sound in Michigan or am I missing anything? 2) Should I add a post in center of truss span at each end? 3) Since we only live on SS I wish to try to keep costs down and wonder if I could downsize the posts to 4×4’s? Thanks!”

For sake of discussion I will assume “front” to be a gabled endwall. If so, and your existing garage is structurally sound, you can probably just add a ledger board securely attached, rather than needing another truss.

Provided this can be done, I would place four UC-4B treated posts at 12′ and 24′ from existing building (two on each sidewall) and entirely backfill holes with concrete (this is a roof only building, lack of concrete encasement will likely result in racking of building). No, these cannot be 4×4. Use a single truss on front endwall and a pair of trusses at 12′. 2x purlins, on edge, joist hung between trusses (or to ledger).

We could engineer and provide this building for you, utilizing site built trusses, to further reduce your investment, as well as it would be fully engineered. You won’t need to have headers (aka truss carriers) or a column at center of each endwall.

Repurpose – From Pole Barn to Barndominium

Reader LAUREN in THORNVILLE has an existing pole barn and writes:

“Hello! We have an existing 40×64 post frame construction pole barn that is 16′ high at the eaves/trusses and 20′ total height. It has siding and half of the space has 6 inch poured concrete. We would like to turn this into a one and a half story home. The one and a half would go on the part that does not have poured concrete. How far down would we have to dig to make that happen? I assume more than 2 ft to get to the 18 ft two story height  just to take into account the height of additional concrete pouring etc. I also wonder if half it already has poured concrete if it’s still possible to do water lines and electric in that area and then put additional flooring on top of the concrete so the space in between is running the necessary lines? we will not be doing this ourselves we will be hiring contractors but wanted to discuss the possibilities of what we can do with the structure. This is an agricultural pole barn, so do we need something different to make it into a habitable home since the wood poles etc are probably different than home grade? I appreciate your answers to these questions as well as any other advice or opinions that I did not think of that you can offer.”

Before you get overly deep into this, I would recommend you hire a Registered Professional Engineer to do a thorough evaluation of your existing building and give an opinion as to structural upgrades necessary in order to bring it into compliance with R-3 (residential) occupancy. This, alone, will likely curb your enthusiasm for trying to repurpose your structure. While either agricultural or residential columns should be pressure preservative treated to a minimum UC-4B specification, this is sadly not always what has been used. You are most likely to find your existing columns (wood poles) are not large enough, in dimension to safely support a residential use and their concrete footings are inadequate. In order to get to an adequate two story height (https://www.hansenpolebuildings.com/2020/05/how-tall-should-my-eave-height-be-for-two-stories/) you would be not only doing a lot of digging, but also having to provide a continuous foundation of some sort between columns. In your existing slab area, should you need to run under slab utilities, it would probably be least expensive to rent a concrete saw – cut slots in slab and fill back in.

My recommendation is to build a brand new fully engineered post frame barndominium to best fit your family’s wants and needs.