View Full Version : Do I need to vent a flat roof?
 
 azhuettl
Jul 29, 2012, 01:20 PM
Building new guest house in Arizona.
Flat roof 1:12 pitch, 24' span
Spray Foam insulation top (1")
Plan on bat insulation above ceiling.?. 
So. Do I need to vent this roof?
 creahands
Jul 29, 2012, 03:30 PM
Yes
 
 Chuck
 azhuettl
Jul 30, 2012, 04:40 PM
yes
 
Chuck
 
 
Hi.
So how many vents and where?
Roof is already sprayed, so can I vent from the side?
Thanks
Tom
 creahands
Jul 30, 2012, 07:00 PM
If u have soffit at front and back, vent between each rafter.
 
Chuck
 azhuettl
Jul 30, 2012, 10:14 PM
If u have soffit at front and back, vent between each rafter.
 
Chuck
 
Hi
No sofit's. Adobe style house. Will try to attach picture.
Old picture. Roof is foamed and walls have styro and lath already.
Walls go straight up to top.
Tom
 creahands
Jul 31, 2012, 05:48 AM
Install venting on the roof side of the parapet wall and drill holes in plate. Use 2'' round 5 or 6 vents. This will keep wall face neat looking. In rear u may have to mount vent in wall.
 
Chuck
 azhuettl
Aug 7, 2012, 08:41 PM
Install venting on the roof side of the parapet wall and drill holes in plate. Use 2'' round 5 or 6 vents. This will keep wall face neat looking. In rear u may have to mount vent in wall.
 
Chuck
 
Hi
We finally decided to foam the inside of roof making it a sealed space. I like the ductwork not being in the heat while they carry my AC air. 
Thanks for your input on this.
Tom