[rick32]

I'm replacing the roof on the back of my house and need to know how thick the decking should be. The roof is 24' wide and 16' long with a 12-2 pitch. The rafters are 2x6 -16 oc. Theres a lot of standing snow on this in the winter. Also, Would metal roofing be a better choice or wouldn't it make a difference?

 

[Scuba_Dave]

I go with 3/4" sheathing myself on the house
On my shed I went with 1/2"

 

[rick32]

Thanks for the reply Dave:thumbsup:

 

[Scuba_Dave]

Is it a 12-2 pitch? or a 2-12 pitch ? There is a difference

2 in 12 is 2" up for every 12" of run (low slope roof)
12-2 is 12" up for every 2" of run - like an A-frame ski house ?


I think based on your measurements it s 2-12, not an A-frame

 

[Ed the Roofer]

If it is a Low Slope roof, with a 2" Rise for every 12" of Run, then a flat roof material is what that is typically designed for, but a proper sheet metal panel roof specification could work also.

The underlayment water-tightness and the flashing details will be critical though.

Ed

 

[rick32]

Thanks Ed. On another note, my sisterinlaw has 3 dormers that vent her attic. She wants to replace the vent slats with windows and refinish the attic into living space. If we insulate everything and seal it off, dose she still need vents? We live in southwestern NY.