Resilient basement flooring
louis123
| Posted in General Questions on
Hello
Building a basement to be confortable and wet flood proof.
I want to use 1 inch foamular 600 above the slab with a vinyl flooring. (Already 3 inch foam under the slab)
Usg says not to use durock under vinyl.
What should i use on top of the foamular that is water proof? (Not plywood)
Thanks for your help!
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Replies
LVT can only be installed over solid substrate (concrete or OSB/CDX). If you must have the formular 600, and don't want wood, your only option is to pour another layer of concrete on top.
Since you already have the insulation bellow the slab, not sure why even add the extra layer of rigid. Install the LVT over the current slab and call it a day. You can get LVT with thicker padding on the back which helps take some of the edge off heel-strike impact.
Hi Akos,
Thanks for your suggestion.
I was really hoping to add some insulation on top of the concrete for added confort.
I taught some products other the durock could be suitable to use under viny. On their installation instructions, Armstrong says to use cementious board suitable for underlayment.
>"I want to use 1 inch foamular 600 above the slab with a vinyl flooring."
Foamular 600 is XPS, blown with a mixture of extremely powerful HFC blowing agents, making it BY FAR the least green insulation in common use in North America, roughly an order of magnitude higher impact than EPS.
https://materialspalette.org/wp-content/uploads/2018/08/CSMP-Insulation_090919-01.png
Their (recently released) Foamular-NGX 600 is blown with much less impactful HFO blowing agents that reduce the impact to that of EPS of the same density, but it's going to be substantially more expensive, and may be hard to find.
Given that it's fully supported by the slab everywhere the isn't really much point to using the high density 400/600/800 engineered versions of foam. It's supporting a floor, not the full weight of the house. With something only as stiff as half-inch plywood for a subfloor over to distribute the weight even a half dozen 200lbs Czechs dancing the polka with a keg of beer on each shoulder wouldn't dent even Type-II EPS (1.5lbs per cubic foot nominal density.)
Since you already have 3" of insulation under the slab (R12.6, assuming either EPS or XPS fully depleted of it's climate-damaging HFCs) it's fine to just skip the foam, use whatever concrete leveler you like and put the vinyl flooring directly on the slab (along with any manufacturer's recommended underlayment.) The extra inch of foam barely moves the needle on energy use for the house, and the cost (environmental and financial) is better applied elsewhere, somewhere that get's a better bang/buck (or bang/CO2e ).