Sawmill Shed Planning

[memopad]

I think it's finally time to start building a roof to park my sawmill under, and any other toys that I can fit! 

I was originally designing a simple monitor style barn with the center stall being maybe 16'x36', and having 12' wide lean to on each side. I've since decided to buy trusses and do a more traditional pole building at 24'x36', with plans for a 12' lean to on one side (or continuation of the roofline over the lean to). 

I typically copy the design of the professionally built pole barn on our property that was built 20 years ago. It has laminated 2x6 (3 boards nailed together) posts at 6' centers, with a truss on top of each post. Then typical 2x4 purlins for the roof metal, etc. Reading on here, I've heard about other companies doing 12' spacing on posts, doubling up the trusses on the posts, and spanning those with 2x6 on joist hangers for the roof. I'm really interested in this for the wider post spacing. My question is if I'm using stock 24' trusses from Menards they give me 70lbs snow load at 6' spacing. If I double the trusses, does that give me 70lbs snow load at 12' spacing? Is the math that simple? If I'm using half as many posts, can I stay with the laminated 3 2x6s or do I need to do something bigger? Thanks for the help!!

[Don P]

Go to a real truss shop/ post frame/ roof metal, supplier.
They will design the building you want and provide the materials, and crew if you want.

If possible on the sawmill side have them cantilever the trusses so there are no posts on that shed side.

[memopad]

That would be slick but I'll probably use my own lumber on the lean to to save money. I'll be building this myself, hoping to have the basic posts and roof done for around $2500. Budget build on this one.

[Don P]

Then yes, all things being equal doubling the spacing on the trusses doubles the load on them, doubling the trusses takes care of that. the purlins have double the span times double the load, the bending force on them quadrupled rather than doubling.


The trusses here cantilever out, about 7' to the drip line IIRC. The Belsaw has no posts on this side of it, which is sweet. If I bump into my sawshed a few more times I'll rebuild it like this.

[Larry]

I've since decided to buy trusses and do a more traditional pole building at 24'x36', with plans for a 12' lean to on one side (or continuation of the roofline over the lean to).

Do as Don P suggested and go to a real truss company.  Tell them what you want and they will design a truss that works.  Ask them to give you options.  Cantilever shed is easy.

I had Morton Buildings build a machine shed 30 years ago.  They built it similar to what you suggest only with 10' spacing between trusses.  It was a great design.  I've also built five buildings since, all different and two with home made trusses.

A free publication that has been around forever with good ideas.
Farm Shop Plans

[memopad]

Man building a pole barn alone is a really slow process... I'm about two months in to the project so far with a long way to go. The main structure is 24x36, and the roof line will continue down over a 12ft wide lean two on one side. 



I really don't like setting posts.



Had a couple of friends over to help set the trusses. I was able to lift them most of the way with the tractor, we only had to muscle them the last foot or so.





How it sits currently: Lean-to posts are in, ready for more headers and then rafters. I'm going to cut some 2x12's on the mill for the headers, and then a 6x12 or so beam for the center span of 18ft. I have some straight clear red pine to use for the beam. My plan is to get whatever height I can for the beam at 6in width from the tree. Should be at least 12, maybe 14" tall. If I have a sag problem this winter I'll add a temporary post till the snow is gone. Snow load is 70lbs in my area.



I also have some grade work to do. I'm going to dig material out of the small hill on the far side of the barn and use that to fill in and around the pole barn. Eventually I'll top with some gravel or something.

[barbender]

That looks great!

[memopad]

Question for the brain trust;

If I cut my own 2x12 headers that rafters will sit on, and roughly 6x12 for the beam that rafters will also sit on, do I need to account for using green pine lumber? I'm assuming they should both shrink eventually to a similar dimension, and the rafters might end up half an inch lower after it's dried. I'm probably over thinking it, but since the roof line will be continuous I don't want a big warp in the metal roofing.

[Don P]

I suspect you are about right, the 6x12 will shrink but it'll check, so it won't change dimension as much as a 2x12 that will shrink in dimension without checking.

[csobel]

Nice work; keep it going!

I was surprised at how much work it took to get my 50x60 post frame going. It's more of a finished building though. I had a crew do the outside framing and we worked together on the roof and siding... besides the electrical and HVAC I'm doing most of the work. Some days I regret this; it never ends up cheaper that way for me because I end up upgrading elements of it, or having to buy tools. But working by yourself on a big building is slow.

[memopad]

Progress has been slow but steady'ish. I finally have the roof on and the sawmill in its new home. I was milling some white pine for siding boards the other evening while it was raining. Total game changer! Now I need to build a log deck of some kind to stage logs for the mill without needing the tractor.

I milled the beam from red pine, I think it's about 7x13 . The headers on either side are 2x13".






Even though it's just a 4/12 pitch, I was having a hard time getting enough grip to stand up there. I had to find some old gym shoes and change out of my boots on the ladder to keep them clean or I'd slide. I don't ever want to climb on this roof again! The white panels over the lean-to are plastic and act like skylights over the mill.


The mill in its new home. I buried some old land scape timbers under the supports, feels very stable so far.


I'm going to skirt the bottom of the building in metal to act as a splash guard. I was going to go with board and batten but decided to just put the boards up. It won't be a finished interior so having it weather tight won't matter. Above the board siding on this wall is clear paneling to let some light inside. So far the boards are all white pine recovered from a tree that blew down last fall. I have other species (red pine and jack pine) that I'll probably mix in with the other walls.

[barbender]

Man that looks great!