Tag Archives: lean-to addition

Vapor Barrier, Gothic Arch Truss Design, and a Lean-To Addition

This week the Pole Barn Guru addresses the need for a vapor barrier as well as some framing recommendations in a future build, the possibility of a Gothic Arch truss design with glulaminated columns, and the addition of a “lean-to” to a 2016 Hansen Building. 

DEAR POLE BARN GURU: Hello Mike, Our monitor style home has been designed by your staff and we are putting together financing and logistics details edging closer to ordering our materials package. Still a bunch of questions to ask of the Guru. We will be using an AIB under the steel siding with rockwool insulation in the cavities. I believe we will need a vapor barrier on the inside. I will be working alone on a lot of this construction and don’t look forward to wrestling with plastic sheeting for our vapor barrier. I would like to use a rigid insulation board such as r-tech or r-max with taped seams to accomplish this. I’m thinking it will much easier to seal electrical boxes and such with something rigid. What’s your take on this approach? Do you feel it is a safe and effective way to accomplish this? Thanks as always for your great information! RUSS in TILGHMAN

DEAR RUSS: Yes, you will need a vapor barrier on inside. I have suggested this very same solution more than once, as it looks like both reasonable to install and a way to minimize thermal transfer. I would recommend windows and door openings in commercially girted walls be framed out with one dimension larger members (2×10 rather than 2×8) and use 2 inch insulation boards, for ease of attaching finish trims on interior. You might also want to go with 2×8 treated bottom plates, for this very same reason. Insulation boards can be taped to these one size larger members.

 

DEAR POLE BARN GURU: Looking to use laminated Gothic arch design trusses, 4 foot on center anchored to 1st floor continuous floor trusses 16 inch on center with two rows of support beams at 12 foot under floor trusses. 2nd floor planning on recreation and residential area. Need to have plans drawn up to meet codes. Would this style post framing be sufficient for truss kick out using a truss bass shoe and steel gusset plate at ridge? Possibly add some knee walls at 1st floor framing for added support. Help me out, kinda designing on my own until I get prints. Thanks, ROGER in SOUTH HAVEN

DEAR ROGER: At one time I had actually acquired a set of plans for an old Gothic arch design. Tried to get them to engineer out and regardless of what lumber was used, could never get them to work. It might be possible to have glulams made to conform to your arch form, however I fear it would be phenomenally expensive. Should you be determined to follow this path, I would recommend you reach out to Travis at MSS Engineering (260)267-7414. He is registered in Michigan, and if anyone can make it work, it would be him. Best of success in your endeavor.

 

DEAR POLE BARN GURU: I purchased a 24′ x 36′ pole barn from Hansen in 2016. I has an 8′ lean-to on one eave side making its total dimensions 32 x 36. I would like to add a 10′ enclosed lean-to on the other eave side. Since my building is one of yours, can you design and price it with the same siding colors and account for snow load and the pitch of the new roof? KEVIN in FORT WAYNE

DEAR KEVIN: Absolutely we can assist you with this. One of our Building Designers will be reaching out to you Monday to discuss further. If you have enough available space, you may want to consider coming out 12 feet, as your investment will be very similar.

Insulation, Lean-To’s and a DIY

A Bonus Ask the Guru for this Thursday’s blog for Insulation, Lean-To’s and a DIY 

DEAR POLE BARN GURU: I have a 30×40 pole barn with 6″ purloins mounted between the posts. I’m planning to add minimal insulation using closed cell panels. I’ve seen recommendations to cut the panels to fit between the purloins (would be up against metal) ang using great stuff to seal gaps/seams. I’ve also seen recommendations to attach panels to inside of purloins and seal with tape, which would leave roughly 5.5 inch air gap. However, the air gap would have little real ventilation due to the purloins. It would just be lots of “pockets”. I plan on putting 1/2 inch plywood over the insulation. Note…this is a coastal area with direct sea breeze and I’m only insulating about half of the barn, if that matters. Interior walls with fiberglass batting will separate the heated/unheated areas. RAY in SOUTH BEACH

DEAR RAY: Other than if you intend to use closed cell spray foam insulation applied directly to underside of your roof steel, there is no other ‘right’ way to insulate between your roof purlins. Here is a story from another person, in a similar situation: https://www.hansenpolebuildings.com/2023/10/properly-insulating-between-roof-purlins/

 

DEAR POLE BARN GURU: I’m wanting to add a 20′ lean to my 40x60x14 barn. Lean I would like is 20x60x12 but not sure if this work? What size do lumber for rafters for that span and how close together? Put 29ga metal on roof enclosure of 2 ends

Thank you. ALAN in MERIDEN

DEAR ALAN: Adding a lean to may look quite simple, but can be fraught with unknown challenges.

Your existing building should be checked by an engineer to insure columns on side you are attaching to are adequate for newly imparted loads. Rarely will footings along this side of your existing building be adequate in diameter to now have to support twice as much load as originally intended. Snow drift zone (along each side of ridge of existing building), will become significantly wider on side of ridge opposite your lean to addition.

It may prove most prudent, to place another set of columns every 12 feet along your existing building sidewall to support your lean to. This would also eliminate having to cut into your existing wall for attachment.

If your intention is to clearspan 20 feet rafters will probably have to be either LVLs (Laminated Veneer Lumber – read more here: https://www.hansenpolebuildings.com/2015/02/lvls/ ) or we have ultra high strength lumber available to fabricate wood roof trusses with your very low slope and not take up any more headroom than absolutely needed.

Another consideration is your proposed 1.2/12 roof slope will void paint warranties on your new addition roof steel.

 

DEAR POLE BARN GURU: Hi, I’m very interested in getting one of these, but do you install them? Or do I need to find someone who knows how to? The answer will determine whether or not I buy. ROBEY in CERRILLOS

DEAR ROBEY: Hansen Pole Buildings are designed to be erected by any average physically capable person who can and will read directions. We have had clients from septuagenarians to father’s bonding with their teenage daughters successfully erect their own beautiful buildings, often saving tens of thousands of dollars while doing so.

Thousands of DIYers, in all 50 states, have built their own Hansen Pole Buildings. You can see photos of their work on our website.

Your engineer sealed building plans are specific to your building, on your site and include location and connections for every member. Details on plans are keyed to specific sections of our step-by-step Construction Manual guiding you through every phase of assembly. Even your lumber package comes with board ends of specific members color coded to match their location on your building. You don’t even have to drive nails, as we provide structural screws for assembly!

Get stuck, can’t find an answer or just want to confirm something? Our Technical Support team (who have actually built buildings) provides unlimited free assistance.

While some of our clients do hire building erectors, it is certainly not a necessity to do so (and no, we are not building contractors in any state).

Occupancy, a Single-Slope Residence, and Lean-to Addition

This week the Pole Barn Guru take care of reader questions about getting an occupancy permit in Victor ID, the size and scope of building a single-slope with a loft, and the addition of a lean-to to an existing structure.

DEAR POLE BARN GURU: I follow your posts and have seen some who question if a pole building can be built as a home and get an occupancy permit. I have some property in Victor Idaho, Teton County Idaho building department. My question is: Can I build a small (about 1200 square feet) building in Teton County Idaho and get an occupancy permit to live in it? Thanks! AL in SURPRISE

DEAR AL: My first experience with Teton County was nearly 30 years ago – when, as a General Contractor, we built a post frame building for Driggs Plumbing. Fully engineered post frame buildings are 100% Code conforming structures and when designed appropriately for Risk Category II and a R-3 (residential) occupancy they make for excellent homes. I have read through Teton County’s Building Department information online and see no minimum footprint requirements for homes, however you would be best served to give a call to Teton County’s Planning and Zoning Department at 208.354.2593. https://www.hansenpolebuildings.com/2020/01/your-barndominiums-planning-department/

 

DEAR POLE BARN GURU: Hello. We are in the planning stages of designing our home and are thinking of building a 40×60, single slope home with a loft on the tall side. Have you ever designed anything like this? I am having a hard time figuring out what height walls I would need and what pitch roof in order to accommodate a loft. I am thinking that i would like 10’ ceilings and 8’ ceiling for the loft, but worried that being vaulted, I will lose usable room space fast. Please let me know if you can help. Thanks! NATE in BIXBY

DEAR NATE: For sake of discussion, let’s work from a 12′ loft width. Allowing for your requested ceiling heights at low side of loft, and thickness of floor and roof system, a 22′ height is not unrealistic at this point. With a 3/12 roof slope (typically a minimum to prevent voiding roof steel paint warranty) your eave heights would be 25′ down to 15′.

 

DEAR POLE BARN GURU: How to tie a self-supporting lean-to onto my existing pole building? Ham Lake city inspector said my existing pole building footings don’t support the added weight of a lean-to and therefore need posts on the high side of the lean-to. Pole Building is 30×64. Lean-to is 19×64. Ham Lake inspector says you don’t need to tie the buildings together other than the lean-to roof tucked underneath the existing roof. The 9 posts on the high side lean-to will be 1′ away from the existing 9 post on the Pole Building. I want to tie these two posts together. I’m thinking of cutting a hole in the siding and nailing a 2×6 onto each post at the top somewhere. Do you have any suggestions? Thanks. KEITH in HAM LAKE

DEAR KEITH: Your Building Inspector is absolutely correct. I see far too many cases similar to yours where a lean-to is added onto an existing building and due to inadequate footings results in an up-and-down roofline. Not certain why you would want to go through efforts of trying to connect those columns, and any meaningful connection could result in loads being inadvertently transferred between buildings. To me, it sounds like more work and efforts than it could ever be worth. We had this very same situation when we added a 30′ x 96′ lean-to to our 96′ x 96′ warehouse. We did not tie columns together and have never experienced any sort of negative challenges from it.