# 3/12 vs 2/12 covered porch roof slope and the risks of water issues where it ties into the wall?



## Flash Master (6 mo ago)

I am in the final stages of a house design and the only consideration left to address is the slope of the rear porch roof. As drawn, it is a 3/12 pitch and will be metal but the issue is that given the porch depth, the height where this roof adjoins the house (along two bedrooms) will result in windows with rough openings starting 40" above the subfloor which is too high aesthetically.

This can be solved by dropping to 2/12 or 2.5/12 (if that is possible), but how much does my risk of water issues go up when dropping below 3/12 for such an application? Is it safe to assume that proper roof-to-wall flashing / sealing techniques exist so that there won't be any issues?

The house will be located in central NC, so snow isn't much of a concern.

Any thoughts or ides on this topic are appreciated! THX!


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## roofermann (Jul 7, 2012)

Depends on the type of metal roof. True standing seam with hemmed ribs- zero issues. Snap-lock metal panels- use an I+W as underlay. Exposed fastener panels- No.

I think that pitch would be too low for any type of metal shingle too.


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## Flash Master (6 mo ago)

roofermann said:


> Depends on the type of metal roof. True standing seam with hemmed ribs- zero issues. Snap-lock metal panels- use an I+W as underlay. Exposed fastener panels- No.
> 
> I think that pitch would be too low for any type of metal shingle too.


Thx! I'm hoping to avoid standing seem but if the 2/12 can be safely done with other types of metal roofs + IW which would extend up the wall a bit then it sounds doable.


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