Basement subfloor...again

Users who are viewing this thread


New Member
Reaction score
Washington DC
Hi all,
I've read the numerous discussions about installing basement subfloors, and have especially appreciated the advice in the other threads provided by Dana. I have extremely limited headroom in my basement so I have decided on the following for the subfloor:
a) 6 mil poly on slab, seams taped
b) 1/2 inch poly-faced EPS
c) 15/32" plywood
d) 6.5 mm LVP

I really just have a few clarifying questions:
1) Should the 6 mil poly be directly against the slab or between the insulation and plywood? Seems like either way may be OK, but not sure if there is a preferred way.
2) Should EPS seams be taped (in addition to any seams in 6 mil poly)?
3) Is poly needed if the EPS is already faced with plastic?
4) I will leave a 1/4" gap between subfloor and bottom plate. Should 1/4 gap also be left between sheets of plywood to allow for expansion?
5) My walls are already built and drywal attached, so I can not take poly to the foundation walls. Should I try to attach the 6 mil poly to the bottom plate?
6) Any reason to use laminate flooring over LVP?

Thanks for the advice!
Last edited:
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks