Can you put a vapor barrier under floating LVP on concrete?
Flooring store salespeople often advise that floating luxury vinyl plank cannot be installed over a vapor barrier. This stops people from confidently finishing older concrete garage pads, because they want to lay a 6-mil barrier first to keep the floor solid, comfortable, and protected from the cold.
What the numbers show
Counted from the threads quoted below. How we count
- People have been saying this in most months since September 2026.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
Can you put a vapor barrier under floating LVP on concrete?
- 1Accepting salesperson advice against using vapor barriersDid this help you?
- 2Floating rigid XPS foam boards under floating plywood layersDid this help you?
- 3Fastening pressure-treated sleepers to the concrete and cutting foam to fit between themDid this help you?
- 4Using pre-manufactured insulated subfloor panels designed specifically for concrete slabsDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I've got about 350 sq. ft. of a 40 year old poured concrete pad in a garage that I want to finish.”source ↗
“I want the floor to be solid, but comfortable. I'm in the USA in New England so it can get pretty cold.”source ↗
“For simplicity I was considering that option, but I'm def concerned about cold floors.”source ↗
Where this came up
People with this problem also raised
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- 4Can you put new flooring over old pine boards without a subfloor?
- 7Can you install LVP flooring room by room?
- 5Can you put heated floors under luxury vinyl tile?
- 2Cheapest way to build a floor on bare earth in a garage or shed