Engineered hardwood floor in basement
We have purchased engineered wood flooring for our basement. We are are also installing it on the main level. We wanted to avoid vinyl flooring and carpet due to chemical sensitivities; tile wasn’t in budget; and due to height requirements on the stairs, unfinished concrete wouldn’t work. Our original installer planned to glue down with Dritac Golden Bullet 4141. Unfortunately, that installer no longer has time for our job and we are getting a lot of resistance from other installers about glue down. Height is an issue (due to how exterior doors are set) and I would prefer to avoid floating floors, as I would like to have the ability to refinish in the future and there are really long runs of flooring. Is glue down the best way to go? Our basement is a walkout, very dry, mostly above grade (built on a hill). Glue down has been approved by flooring manufacturer. Are there any other options other than glue down or float plywood and nail to that?
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Replies
Carolyn,
We need to know more information before we can provide advice.
1. What is your geographical location or climate zone?
2. Is there a continuous horizontal layer of rigid foam beneath the slab?
3. If there is horizontal rigid foam, how thick is it?
4. Is there a layer of polyethylene under the slab?
It's also a good idea to check the slab's moisture level with something like a Tramex CME4 meter. You also need to check the slab for level. I bet there are high and low spots that need to be addressed.
I'm also curious about the other installers. Are they offering up a common objection or a bunch of reasons for why they don't want to glue down your flooring?
We are in the lower peninsula of Michgan. We do not have rigid foam but do have 6 mil poly taped at all of the seams. Moisture level in the slab will be checked. It was check 6 months ago and there were no issues, but will also be checked right before install.
I think glue is messy and a lot of guys don't feel comfortable with it. Most are recommending a sheet of poly and then a plywood subfloor. Which causes an issue of height with exterior doors for us.
Carolyn. Here is a similar scenario and the recommendations offered by GBA (https://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/what-s-best-basement-flooring-system). I suspect you will need to install rigid foam and a plywood subfloor as well.
We cannot have the total flooring height differ that much from the stair tread height of 3/4" and the main floor height of 1/2" (cannot differ more than 3/8"). Is there a super thin subfloor option?
Carolyn,
I don't think there is a solution that will meet all of your needs. You are asking for a solution that won't require you to rebuild your stairs or raise your door, but that solution doesn't exist -- or it costs more than you want to pay.
Any thin flooring installed on an uninsulated basement slab comes with the risk of summertiime condensation. That's because the flooring will be cool. If you are willing to accept that risk, the thinnest solution is ceramic tile. But you've told us that "tile isn't in the budget."
Evidently the engineered flooring manufacturers allow their product to be glued to a basement slab, but installers who have looked at your job don't want to do it that way. I don't blame them. They may have past experiences with customers who have been disappointed with flooring glued directly to a basement slab, and they don't want to go down that road again.
If you want a finished basement, the best solution will include a continuous layer of rigid foam above the slab. That fact will affect your stairs and your exterior door.