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View Full Version : Adding a porch-like overhang on a framed shed?



ducsauce
May 18, 2010, 07:26 PM
Hey guys... I'm in the process of building a 10x15 shed and have decided that I want a overhang of about 6 feet on one of the gable ends. Its actually on the gable end where I have a 6 foot opening for a double door. The problem is that I have already framed the building. The walls are up (no siding on this end yet) and the ridge and rafters are in place. How difficult would it be to add this overhang now? I want it to be the same pitch (5/12) as the roof. Pretty much I would just be extending the roof out 6 feet.

Here is a pic I found that is similar to my situation except I have a 2x6 ridge with 2x4 rafters. Also, there is a six foot opening on the end where the guy is standing. .

http://img.hgtv.com/HGTV/2004/03/19/lds603_rafters_lg.jpg

creahands
May 18, 2010, 07:56 PM
Will u be putting a ceiling in this area?

To add the 6 feet and not build a gable end and ceiling, will not be structurally sound.

The framing for rafters will have to have a collar tie 1/3 down from ridge. Going from collar tie to ceiling beam, will need support beam dividing length of ceiling beam in 3rds. This will give a truss appearance.

When sheathing roof, be sure ply wood extends into existing roof for added support.

Chuck

KBC
May 18, 2010, 08:07 PM
If the rafters are still open(no sheeting installed),you can add 2X4's across the rafters, from the second rafter through the outside one(on the gable) and out to the next 6 feet.

You would notch the 2X4's in on the end(gable)rafter and all the subsequent rafters to the end(totaling 3 cut rafters)(the gable one and the other 2,the last one(new gable end) and second one inside the existing shed would be butted and nailed only,this would extend the roof line 6 feet,24" O/C)

Set posts for the overhang,build the end wall to support the overhang with header.

If you don't want posts on the overhang you would need to have more support for the overhang, most likely going through the entire shed from left to right with 2X's and extending them out for a free standing overhang, but I wouldn't suggest that(Wind,snow load,etc)

ducsauce
May 19, 2010, 05:37 AM
Thanks guys.

creahands: There will be NO ceiling in this area or the shed for that matter. I had planned on incorporating collar ties in the shed. I wanted to use the "loft" area for extra storage so shelving will also be built which will help strengthen the walls.

KBC: That sounds like a good idea. I put my rafters 16 O.C. (had extra lumber and figured the more the better) so I would continue with this on the extended overhang. So if I understand you correctly, the rafter next to my gable end would have the 2x4 butted up and nailed. Then the shed's gable end would be notched (3.5") so the 2x4 lays flat and it would then extend out 6 feet being notched in every rafter of the overhang.

My ridge beam only extends outside the shed now by 6". I was thinking I could sandwich it with 2 short pieces of 2x6 and then stick one in the middle to essentially extend the ridge beam. How does this sound?

I'm now just trying to figure out to tie everything together. I want this overhang to be completely open with the two posts on the end for support. Where would I connect the overhang's "top plate" to the shed where the birdsmouth will rest?

creahands
May 19, 2010, 02:57 PM
If u notch the rafters, they will loose their structural strength. And not carry very much load.

Remove the end rafter on shed. Extend ridge and sandwich it from the next rafter in shed and 2 feet past joint in ridge. Bolt together with 3/8 inch carriage bolts. 2 bolts at start (exsting rafter) with a total of 5 bolts in each section of ridge.

Cut top plate back to existing rafter and extend plate from that point.

I would suggest putting in one double collar tie in center of over hang. Only need a single, double is for aesthetics.

U may still get deflection from weight of roof on the 6 foot span if u don't put a header in.

Chuck

ducsauce
May 20, 2010, 04:18 AM
So the top plate will be cut and my walls will no longer be tied together so to speak. Because I had the top plates all connected on three walls. Guess that won't be a big deal. Will the extended top plate not have any support except where it ties into the end post? And the header you mentioned will only be at the end of the porch, right?

creahands
May 20, 2010, 04:35 AM
Is your top plate a double? If u do, the walls will still be tied together. The extended bottom plate would be butted up and nailed to perpendicular bottom plate. The top plate would be nailed to bottom plate.

Don't need a header on gable end. U need it to pick u load from roof rafters.

Chuck