Roof truss design (1 Viewer)

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Anyone know of a link to a good guideline to design roof trusses? I'd buy them prefab but... fist of all I'm cheap and second I'm building the cabin on an island and don't want to have to deal with getting trusses over there.
 
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This site has a bunch of truss plans. Truss plans


Hope this helps.

Kevin
Thanks, I actually found that one yesterday.

I am really looking to split the cabin into 2 different rafter or truss designs, one area over bedrooms where a bearing wall is no problem which makes it simple, with a sleeping loft for the kids. The other half will be over a living room kitchen and I don't want any posts or beams. It will be a simple 24' by 24' box with the ridge running perpendicular to the open length of the kitchen living room. Ideally it would be vaulted and open all the way up above the kitchen living room. I think that would require a ridge beam but can't find anywhere that says I don't need ceiling joists.
 
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Thanks, I actually found that one yesterday.

I am really looking to split the cabin into 2 different rafter or truss designs, one area over bedrooms where a bearing wall is no problem which makes it simple, with a sleeping loft for the kids. The other half will be over a living room kitchen and I don't want any posts or beams. It will be a simple 24' by 24' box with the ridge running perpendicular to the open length of the kitchen living room. Ideally it would be vaulted and open all the way up above the kitchen living room. I think that would require a ridge beam but can't find anywhere that says I don't need ceiling joists.

You would still need collar ties if you didn't want ceiling joists but you can probably get away with 1 every 4 to 6 ft and they could be further up the roof not right at the top of the walls. With trusses you could do a scissor truss and not need the collar ties.
 
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You would still need collar ties if you didn't want ceiling joists but you can probably get away with 1 every 4 to 6 ft and they could be further up the roof not right at the top of the walls. With trusses you could do a scissor truss and not need the collar ties.
Ya, I figured I'd need collar ties.
 

bkfj40

Wishin i was in Wydaho
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what kind of snow load do you need to design for? usually, a rafter/collar tie arrangement can work for lighter snow loads. Once you get into heavier snow loads (which I think you might be in) you are looking at either trusses or a ridge beam and rafter arrangement. If you are doing a 24' box and can live with a post at 12', I'd be inclined to do a ridge beam. You'll get a whole lot more useable area.

find out the snow load and shoot me a PM and I'll size some beams and rafters up for ya....


bk
 

AJP

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Oct 20, 2005
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I understand your reservation about prefabbed trusses. However I found that they were pretty reasonably priced for what you get here in Ontario AND they were designed by an engineer to meet the loads and spans the building required. It would be pretty hard to duplicate what I got for the money invested....course transport for you might be an issue
 
Joined
Dec 18, 2004
Messages
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Location
Vancouver Island
 
 
 
what kind of snow load do you need to design for? usually, a rafter/collar tie arrangement can work for lighter snow loads. Once you get into heavier snow loads (which I think you might be in) you are looking at either trusses or a ridge beam and rafter arrangement. If you are doing a 24' box and can live with a post at 12', I'd be inclined to do a ridge beam. You'll get a whole lot more useable area.

find out the snow load and shoot me a PM and I'll size some beams and rafters up for ya....


bk
snow load is 48 psf, i'm pretty sure 2x8s work with a ridge board.

I understand your reservation about prefabbed trusses. However I found that they were pretty reasonably priced for what you get here in Ontario AND they were designed by an engineer to meet the loads and spans the building required. It would be pretty hard to duplicate what I got for the money invested....course transport for you might be an issue
Trusses will be about $1600 plus the cost of getting them to the barge, prolly a couple hundred. Thats assuming the trusses will fit on the truck with the lumber for the rest of the cabin... Then laying the trusses in a flat area until we're ready and then lifting them up there. PITA! Rafters will be less than half that. If I had to pay for labor it might be different.
 
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where can i get a steel roof truss analysis(forces caluctaled from areas and roof cover weight) and design(members and bolted connections)? i would like to see how the whole thing is analysed and designed from scratch
 

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