Converting my attic to a conditioned space
I am planning on converting my attic to a conditioned space so that I can put an air handler up there. I read a great article here on what my options are as far as venting. I do have a couple questions on this though.
My roof uses 2×6 trusses. I had new shingles and vents installed about 7 years ago. They used the can vents. I was going to install a ridge vent and just leave the can vents there and use the rigid foam to create a 1″ ventilation channels and use the spray foam over that etc…
I got to thinking though(uh oh). They installed the cans over the 2×6 trusses so that 2 bays share the same can vent. Unfortunately not all bays would have an upper vent if I just put the rigid foam in place. Was wondering if there would be adequate ventilation if I drilled holes in the trusses up by the ridge(inside the 1″ channel) so that air could flow to the bays that have the can vents?
Thanks in advance…
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Replies
Dino,
You don't provide enough information for us to answer your question.
Is this a gable roof? A hip roof? Some other type of roof?
Does the roof contain any dormers, skylights, or valleys?
Unless you have a gable roof without any dormers, skylights, or valleys, you don't have a good roof configuration for a vented roof assembly.
If you do have a gable roof without any dormers, skylights, or valleys, you can ventilate the roof with soffit vents as intakes and a ridge vent as your outlet. You don't need any "cans" or mushroom vents.
If you have any other kind of a roof -- one with ridges, valleys, or obstructions -- you want to build an unvented roof assembly.
Here are two articles with more information:
Creating a Conditioned Attic
How to Build an Insulated Cathedral Ceiling