Vapour barrier from the late 80's

[petee_c]

Anyone know the specs for Vapour barrier from the late80's? I'm close to VBing my basement workshop and the original owners of the house left a part roll of VB that I am considering using. It's clear poly but a bit thinner than the super6 that u find in tr stores today.


P

[bender]

We used to use 2 mil or sometimes 4 mil. 6 mil was only for r2000 homes. I think it was in 91-92 the code changed to 6 mil.
I would use what you have, just be careful not to damage it when installing the drywall, and have some red tape on hand for the joints and emergency repairs.

[red_langford]

6mm poly is cheap enough, why bother with the thinner stuff?

[petee_c]

thanks for the replies.... currently unemployed so I want to keep the costs down.... however... i do have $48 left on a Home Hardware gift card, that i could use.... or on electrical boxes etc....

I understand that the code has been updated to 6mil, I will think about it.... of course the rest of my basement is not 6mil.... funny, considering they spent money on spray foam for the upstairs insulation....

P

[matt in golden]

Bender,

Do you know what drove the code change? Was it an issue with permiability or more one of durability for proper installation?

Pete,

Though I don't know the answer to the question I asked Bender, part of what would drive my decision was how much of the basement I was going to be VBing. For example: If 60% of the basement and the rest of the house was already done in the stuff you have, and you are not doing a high moisture area such as a kitchen or bathroom, I really question if it would really matter if you just finished it off with what you have especially if it is behind a painted wall.

Matt

[Bill R.]

Using what you have is just fine. Carefull installing and if you happen to damage it drywalling repair it before covering. The up grade to 6 mil was mainly for durability. Use acustic sealer around the bottom plate behind the poly.

Bill R

[bender]

As Bill indicates, the change was about durability much more than permeability.