Attaching to existing ridge, 2×6 or 2×8?
Now that I will be attaching to my existing 2×6 ridge should I increase the depth of the ridge board to a 2×8 to prevent future sagging. He are some current specs., 4/12 pitch hip,asphalt shingles, no snow loads, single story, 2×6 rafters at 24″o.c..
I will be going to 16″ o.c. 2×6 rafters on the new part of the roof. The new ridge will be approx. 30′ long. I will be adding some purlins for ridge support also.
Thanks
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What is the rafter span?
Approx. 16' including the tail. Addition width 26'-5 1/2".
On a regular stick framed roof the ridge is usually 1 size larger than the rafters.
There is not much that is regular on this house TW. Any other issues with using a 2x8?
No, you should be fine. Good luck!
Thanks TW. Now all I have to do is hope Ike doesn't come my way and take all of my work down.
Your ridge should be sized so that the plumb cut of the rafter has complete bearing against the ridge. Most often with low slope roof assemblies this means going up one increment in board size.
(2x6 rafter, 2x8 ridge for example)
Thanks Dt. I think i'll go to a 2x8 ridge. Are there any other issues with using a 2x8 over a 2x6?
Nope. The idea of the complete bearing is to ensure that the bottom of the rafter rests against the ridge. Failure to have that happen can cause a loaded rafter to split starting where the bottom of the rafter hangs below the ridge.
3-16's minimum to fasten rafter to ridge.
They can't get your Goat if you don't tell them where it is hidden.
Thanks Dt. I was thinking of using Simpson hangars for the rafters at the ridge.
Now that I will be attaching to my existing 2x6 ridge should I increase the depth of the ridge board to a 2x8 to prevent future sagging
I will be going to 16" o.c. 2x6 rafters on the new part of the roof. The new ridge will be approx. 30' long. I will be adding some purlins for ridge support also.
Increasing the ridge board has nothing to do with sagging on a hip roof. You don't even have to put posts/purlins underneath the ridge.
You do have to make the ridge at least cover the plumbcuts in most cases. In your case your plumbcut will be roughly 5-3/4" and will only be hanging down past the bottom of the 2x6 ridge 1/4". That wouldn't fail inspection where I'm from. I wouldn't't chance it where your from though.
Could also drop the ridge that 1/4" and then it would be structurally fine.
;-)
They can't get your Goat if you don't tell them where it is hidden.
Could also drop the ridge that 1/4" and then it would be structurally fine.;-)
That would have to be structurally engineered by ...........;-)Joe Carola
I've often dropped ridges a couple inches so that they catch the bottoms of the plumb cuts. The real benefit is that it creates a better airflow system for ridge vents. I've never tried to get away with "only 1/4"" not bearing. I agree that it most likely wouldn't matter but I just never tried it.
I have dropped ridges for the same reason.
They can't get your Goat if you don't tell them where it is hidden.
Thanks Joe. I'll stick with the 2x8 ridge just in case.