Do I need to put in a vapor barrier on both sides of the insulation?

Question

I am framing a wood 2x4 wall against the basement concrete wall and after I got going, I started to wonder if I needed to put a barrier of some sort against the concrete wall before I put in the insulation. Do I need anything in between the concrete and the insulation or 2x4's? I know I need a vapor barrier between the insulation and the drywall, but anything on the other side? Thanks in advance for your help.

Answer 1

AS EVERYONE SAID ONLY ONE SIDE , BUT YOU SHOULD COAT THE CONCRETE WALL SO IT WILL NOT ALLOW MOISTURE TO PASS THROUGH IT AND BUILD UP IN THE INSULATION .

Answer 2

You definitely, don't want it on both sides, that's a recipe for mold.

You do not want to use fiberglass insulation with a vapor barrier against cinder block walls. You will get mold, there is no doubt about that.

If you must insulate, you should use rigid foam board against the block wall. The wall and insulation must be constructed in such a way to allow moisture to escape. A vapor barrier on the interior wall will prevent the block wall from ever drying when it gets wet (and it will). This will lead to mold, rot, and structural decay. the wall needs to allow air flow behind the wall and allow drying when it gets wet.

Testing shows that the walls that dry fastest do not have vapor barriers.

Answer 3

No. Two vapor barriers will actually trap moisture between them.  

This will lead to problems with mold and mildew. A vapor barrier should be between the living space and the insulation. Good luck.

Answer 4

only on the side that is next to where you live.  never put two barriers.

Answer 5

Nope, Just the one side.

Answer 6

No.  Vapor barrier goes to the heat side.  That is the inside of the house.