Need a little advice…
Enclosing a small section (~50 sq ft.) of screened porch to join the main house as finished, 4 season space.
Joists are lower than the interior ones…basically if I slap down some 3/4 advantech, I will still be about 3/4 inch shy of the interior subfloor. [Finished floor will be a hardwood.]
I’m thinking I will just use two layers and call it done…unless someone else has a better idea.
And on a vapor barrier…I’m in the north and am accustomed to using some 6mil on the walls…assume I should use it in the floor here…but where in the flooring system sandwich? Top or bottom? The space under the floor system will be open to the outside.
Replies
Two layers of 3/4 would be fine--it used to be standard procedure to use two layers of plywood--typically 5/8 and 1/2. You could also shim the floor joists with 1x2's. Be sure to use glue so you don't pick up any squeaks.
Vapor barriers aren't typically used in floors. The plywood will serve as a vapor barrier to some extent. Because heat rises and air leaks out of the upper levels of a house (unless it is very, very well sealed), your house acts like a big chimney, and thus floors tend to be under negative pressure. So moist air moving into floor insulation from the building interior isn't a big problem.
Thanks much!
Actually, if it is to be a conditioned space then vb, insulation, HVAC all have to be addressed. Hardwood in a pseudo conditioned space will be nothing but a PITA.