Hardwood floor underlayment options
jroy
| Posted in General Questions on
I recently picked up some hardwood flooring(3/4″ x 2 1/4″) & noticed that a product called insulayment proports to insulate and act as a air barrier when used under the flooring. Is this a bit of a reach or is this a better option than red rosin or tar paper? I live in Massachusetts.
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Replies
John,
Are you installing the hardwood flooring over an unconditioned space? In other words, is this a bonus room over a garage or a cantilevered bay or a house on piers? Because if you are installing the hardwood on a floor with a conditioned room below, you don't need insulation.
I have flooring going into two areas, one above a garage (that has 18" of cellulose installed between the floor trusses below), and on a first floor area that has R30 (fiberglass batts) between floor joists over a crawlspace.
I didn't see a need for anything more than rosin paper for the same reasons your articulate in your response above Martin.
John,
Needless to say, you still need an air barrier. As long as you aren't depending on your rosin paper to be your air barrier, you'll be fine.
Martin
I have always used either rosin or #15 felt for underlayment under solid wood flooring, what would you prescribe for a air barrier material?
John,
For a bonus room floor over a garage, the easiest air barrier would be spray foam at the rim joist, and carefully detailed drywall with airtight electrical boxes for the garage ceiling.
We moved from felt to Aquabar a few years ago. Since the majority of our homes down here arebuilt on crawlspaces, it seems to have limited the amount of buckling/raised edges on our floors. Does not act as an air barrier nor add insulation value though - strictly moisture control:
http://www.fortifiber.com/aquabar_b.html