Visqueen or Tyvek ?

[jackcsr87]

Hello, I,m building a 3-season room and wondering if I can use 6 mil. visqueen in place of Tyvek. The room is 11' x 30' and only 3 sides. I have the visqueen so I'm looking to save a little $$$. Is this ok, or will there be a moisture problem ? Thanks, Jack

[tooltroll]

Well... Visqueen is a damp proofing membrane, Tyvek is an air infiltration barrier (which passes moisture,) so off the top of my head, I'd say moisture would be a problem, but see what others think...

[bkrahmer]

Use Tyvek or nothing at all. Putting a vapor barrier on the outside of the building will allow water to be trapped there, condense, and cause mold/rot/water problems.

[Sweep]

If you want to save money use #30 (15 lb) asphalt saturated building felt. If the room is not used or heated in the winter you don't need an air barrier.

[grumpydasmurf]

Do it right or don't do it at all.

Tyvek or nothing. Ahhh felt would pass approval, and since it's a 3 season room will probably be adequate but at the same time being a 3 season room it can't be that big. How much are you looking to save?! $50???

[Sweep]

The only advantage of Tyvek is that it can be installed as an air barrier if you know how to do it and are willing to take the extra effort. Since he doesn't need an air barrier, there's nothing wrong with building paper as an underlayment.