[66merc]

Howdy folks,

I am wanting to build a 12x16 shed with a 10' front wall, an 8' back wall and a slanted shed roof with 2"x6" rafters across the 12' span.

The plan I'm working on calls for 4"x4" posts on 4' spacing on the front and back walls with 2"x4" filling in between the posts. Instead of a double "flat" 2"x4" top plate I think I will put in a 2"x?" beam with 1/2" plywood sandwiched between.

Wondering what size for the beam? More importantly, How do I keep this thing from twisting due to lateral load? I had planned on using the galvanized metal post fittings that would attach to the top of each post and the bottom of the beam. Also I would put a 2x4 king stud at each end. Is all of this overkill? Is there a better way?

Thanks

 

[Scuba_Dave]

My shed is 10x22 all 2x4 framing 16" OC, no beams anywhere
Yes, seems like extreme overkill
I'd go with 2x8's to span 12' = 16" OC
Double top plate front & back

Do you have a heavy snow load?
My shed was 10x12 originally & I added on 10x10
No worries on twisting or load
I use the metal brackets on the house
I haven't used any of them on the shed

 

[66merc]

Thanks for the reply. Snow load likely not a big problem here in Oklahoma.

I am planning to do the beam since the structure will have 4' fixed windows along the top of the front wall and seems like a 4' window would need at least a 4x6 header.

I suppose I could use double 2x4 instead of the posts. I am going to use this structure for hangout space so I want it to be solid.

Thanks for the recommendation on the rafter size. I likely misinterpreted a span table because I thought it said 2x6 would be ok for 12'.

I'm planning on building this on poured tube concrete pillars. Will 2x8" be ok for the 12' floor span at 16" OC?

 

[Scuba_Dave]

2x6 is right on the edge for 12' distance
For the extra $$ better to go to 2x8 & be sure
My shed has a cement floor on one side
I'm installing patio block on the other - in case I need to access pool pump pipes

Yeah - with a 4' window better to make sure you have the support. I have an almost 10' window but it has 2 posts for support that splits the window into 3 pieces
I'd think a double 2x6 w/plywood in between would work as a beam

2x8 should span 12' according to span calc
But it can depend upon the species of wood
I think I'd be inclined to put cement block or another beam in the middle as added support

 

[66merc]

Yes, I think I will likely put some extra support under the middle of the floor joist spans.

If I use the 2x6 beam on the front/rear walls, would it be better to use it instead of the top plate, with it sitting on the posts/2x4s, or would it be better to use a double top plate and individually install the headers under each 4' span. Seems like it would be easier/stronger to just install a continuous beam on the top, instead of a top plate. I'm just still a little worried about this thing rotating under lateral load, despite the king studs on each end and the galvanized connectors at each post at 4' centers.

BTW, my city does not require a full building permit for this since it is less than 200SF. Just have to get a simple zoning clearance permit.

I suppose as an alternative I could put the beam on top of a "top plate" and then could nail up through the top plate to give the beam a little more support.

Thanks