The remodel will include something we haven't had- a range hood. When I had the roof replaced 4 years ago I asked for a vent to be installed so we would be ready for the range hood. I didn't really think about it at the time, but now I have questions.
The vent is a 6" duct and the cap is only a few inches off the roof deck. The gap from the cap to the deck is only a 3 inches, +/- . Is this too close to the deck?
The range hood has a 7" round option(vertical), or a 3.25" x 10" rect. option. I can use either, is one better than the other?
Will there be much problem reducing the 7" hood duct to match the 6" exhaust cap? Or should I get some pricing on enlarging the exhaust duct?
BTW, the roof is a torch down membrane. Pitch might be about 3 in 12.
I'd check with the hood manufacturer before reducing. The round is better. 3.25x10 = 32.25 7x 3.1416 = 21.99 or 10+ smaller, yet manu. says either. The round is 33% less surface area for grease to accumulate on and easier to work with. Three sheet metal screws at each joint, try to use 45* elbows instead of 90*. Tape all joints and elbow joints with foil tape, and support duct work securely. I'd pay a roofer to install the correct terminal cap: http://www.lowes.com/lowes/lkn?actio...1CM&lpage=none
Check with him if proper one. Be safe, G
Last edited by Gary in WA; 07-22-2009 at 08:45 PM.