Roof pitch calc. and culvert type/depth?

[TWINKLE_TOES]

John, I think we agree. There are a whole lot better ways to frame than with a calculator. /forums/images/graemlins/grin.gif

 

[willy1947]

Thanks for all the information. /forums/images/graemlins/smile.gif

I'm still trying to decide on the size. It is either going to be 32x20 or 24x16. Depends on the price difference. The 32x20 would fit nicely and give me a better building to enclose at some point in the future. The 24x16 is just the bare min. Both would have 1' over hang on the ends and 2' on the side (I think the 2' on the side is standard).

I will be using trusses. Probably 2x4 on 4' centers. I may get them from Menards and they said they come with a 2' overhang standard. I will put one pole in the middle of the gable on each end. Don't think I can span 20' without one. The post will be 4x6 and will have 2x4 bracing to the roof. No concrete floor yet.

Basically, I have never built a building like this before. I'm no "carpenter" dummy /forums/images/graemlins/blush.gif, but I don't want to make any big mistakes. I'm using my parents pole barn as a guide. Hopefully I'll get some help from experienced people.

There are two things I want to make sure happen. I want to make absolutely sure the post are set correctly and the building is square. Secondly, I want to try to get all of the supplies I need down there in one trip. I don't want to run out of parts when I've asked for people to help. It's the little things like getting the right length metal, trim, and enough extra wood for braces I am worried about.

Thanks,
Dave

 

[TWINKLE_TOES]

I think you will do just fine. Common sense and asking question will get you there.
I would shoot for the 20 x 32 size.

Good Luck.

 

[TC18guy]

I'm not an expert, but the way I understand trusses are made to disperse their loads to the walls/beams they are setting on. I don't see why you would need the center posts. My garage is framed 40'x40' walls with no support in between.

As for the size of the building, I'd build it as big as you can now. you'll never regret having the extra room and the expense won't be any cheaper than it is now.

 

[cubhater]

I don't know about the depth of your culverts. Your rafters will be 10 ft 8 3/16 inches long with no overhang. Sorry I couldn't help you with the culverts

 

[PILOON]

Re Roof Pitch etc;

Easiest of all, Yellow pages, roof trusses, give them the dimensions.

They do all the calculations etc, snow loads, storage or home (different specs).
For 32" you'd need 17 trusses and 1 x 3 furring strips to brace her up.
Fabricated trusses are always made from nice dry wood so that a 20' + OH is easily handeled and installed with a 3 man crew.
You walk them in and lift one end in place (upside down) and then the other side.
Once they are all up there you flip them over one by one and toe nail into place with 1 x 3's to brace things.
2 men do the nailing and the 3'rd guy flips them from below with a long 1 x 3 that has a 4" nail at the end to hook the top for pushing/flipping.
If decking with ply/aspenite be sure to respect 24" centers.
Basically a 20 x 32 ft trussing job is a mornings work.

For the first truss, you want to nail a temporary ,say, 2 x 4 vertically on the blbg end with it sticking up higher than the truss.
That's so that that first truss wont rotate over the side of the building.

All told the factories can supply trusses for about the same price as you will pay for the lumber and that's not counting your labor. (except if your helpers cost $1.00 hr and you work for free)

They have no wastage but you end up with all sorts of 6 to 20" leftovers.
Plus they install all those plates with hydraulics.

To build without trusses you'd need to use 2 x 8 rafters (or 2x6+cross ties) and poles and you'd still have sagging as the loads would want to 'spread' the walls.
PLUS them 2x6's or 2x8' will cost more than trusses!

Been there, done that!

For me it's a no brainer. Prefab trusses!

Since you are doing the install, you can optimise spacing of the 1 x 3 braces to best use that attic space for storage area.
If you slide in plywood sheets (before decking the roof) you can obtain lots of useful storage area.