Do I need a moisture barrier under basement LVP flooring?
Installing luxury vinyl plank flooring directly on concrete without a vapor barrier traps moisture underneath, requiring you to lift the material and decide whether to run the barrier up the walls and seal the perimeter. Without this protection, moisture will continue to damage the floor and trim.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1pulling up the flooring to dry it and install a vapor barrier manually
- 2relying on the wax seal to handle sealing between the toilet and flange
- 3waterproofing only the top side of the cement board that will be tiled over
- 4Looking around online for confirmation on correct installation methods
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“One thing I can't seem to get a definitive answer on is whether the walls should be taped with paper tape to make sure no vapor comes up to the floors.”source ↗
“before I go too much further wanted to make sure I'm not doing anything I would regret.”source ↗
“I guess my concern is would any moisture that could come up from underneath start to breed mold?”source ↗
Where this came up
People with this problem also raised
- 2Can you use fiberglass insulation in a basement after flooding?
- 2Painted concrete basement floor keeps dusting and crumbling
- 2Can I insulate and finish basement walls if they get damp?
- 4Do I need a waterproof membrane under tile on a concrete floor?
- 21How to tile over an uneven subfloor without tearing it up
- 2Do I need a vapor barrier over rigid foam in a basement?