Architect Steve Baczek Discusses Wakol Roll-On Subfloor Sealer
I was watching a Youtube video from Architect Steve Baczek about his Build Show Boston project and at minute 23:10 he interviewed the New England Rep for a company called Wakol.
https://www.youtube.com/watch?v=FBjB9xJhpco
They make adhesives for installing engineered wood floors but they also make a roll-on floor sealer to help prevent moisture from migrating through the sub-floor plywood (or OSB) and into the finish flooring.
I knew that in the old days flooring installers would put a layer of rosin paper between the subfloor and finish flooring to help with moisture issues but I hadn’t heard of a roll-on product before. Apparently one coat of it acts like a moisture resistant barrier on wood subfloors but two coats on a concrete substrate acts as a moisture blocker.
https://www.wakol-usa.com/Flooring-Adhesives/products/Substrate-Preparation
I know a lot of people have asked questions in the past about how to properly install a wood floor over concrete. Has anyone used this product before? It’s out of Germany but they say they have reps all over the USA.
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OMG! Am I controlling the universe :)
I find this video from Steve Baczek on how to prevent moisture from migrating up through your wood and concrete substrate and ruining your finish flooring (which is especially true in a basement) by using a roll-on moisture blocker and now there's an article called "Planning and Prepping for Basement Flooring" by Mark Petersen.
Maybe I'm sensing things about to happen a few days in the future.......LOL.
If you put a vapor barrier over a wooden subfloor the moisture would be trapped in the subfloor and it would rot. For wood over concrete you'd want to put the Wakol over the concrete and the subfloor over that.
In the technical data sheet they do say that Wakol can be used over wood subfloor under tile, but that would be to protect the wood from moisture from above.
The Wakol datasheet does give a perm rating of 0.47. I'm glad to see that, it seems that many manufacturers shy away from providing that information. Many waterproof coatings like Drylok and epoxy actually are quite vapor permeable, it's hard to find a vapor barrier product for use on concrete.
Looking online it's about $100 per gallon, 400 Sq Ft per gallon. So it's kind of expensive but not terrible.
DC, do you think you'd still need to apply something to the concrete if there is a vapor barrier and 4.5" of foam under it? I was planning on my assembly being Earth-->gravel-->R16 insulation with built in vapor barrier (brand is Amvic)-->7/16 OSB-->hard woods
All you need is one vapor barrier somewhere in the assembly.