Please do NOT install over hardwood. I don't care if it is glued down over concrete or nailed to plywood. Vinyl and wood FINISHES do NOT work together. In fact the chemical transfer (and this is the LEAST of your worries!!! ahem!) from the wood finish to the vinyl is almost 100% guaranteed. That chemical transfer = heavy staining of the vinyl. And heavy damage to the wood floors underneath. Which renders BOTH floors unusable. And if the new owner finds out about the damage to BOTH inside of a year (or two...depends on your State's liability laws) you will STILL be on the hook for the damage/removal/replacement. The BIGGEST issue is NOT the staining - when dealing with glue-down hardwood over concrete. The BIGGEST issue is moisture damage and mold/mildew contamination. Concrete breathes and gives off moisture. The adhesive used to glue the wood is a moisture barrier but it never really 'cures'. It stays flexible. When you put vinyl over the wood you CAP the moisture. You TRAP it. That bit of moisture in the GLUE then soaks into the wood...that wood stays soaked and NOW you have huge amounts of mold growth. The chemical staining of the vinyl then SPEEDS UP. Instead of taking 5 years to stain the vinyl (over plywood subfloor) the soaked wood causes the chemical staining to occur in 1-3 years. That's when you pull up your vinyl to find the soaking, molding, useless mess. Now you have to do it all over again but this time with MOLD REMEDIATION costs added in! It's your call. But the installation instructions clearly state not to do it. They don't do this to p!ss off customers or to cost the homeowner more money. They do this to PREVENT irritation and to PREVENT greater costs later on. You wanted vinyl. You currently have hardwood. You will need to pay the piper to get this done properly. Of course if you used laminate you wouldn't have this issue. You could have run the laminate right over top of the hardwood without issue....just sayin'.

I can attest to what SJ McCarthy explains: the previous homeowner in the house I bought couldn’t be bothered with taking out old flooring before slapping another down. The flooring was so thick that the counters in the kitchen were ridiculously short, and yes: the dishwasher was bricked in! When I remodeled it took my flooring guys six days to jack out four layers of flooring before laying new tile. When all was said and done I found the interior doors and their jambs had been shortened as well! What a huge, expensive PIA to fix. If you’re not going to do the floors right, please just leave them alone. The future homeowner will thank you.

Mike A- There's more to it than putting on a respirator and pulling it up. Personal protection for asbestos abatement people is the easy part. It's all the other things you do to prevent the spread of fibers throughout your house and ductwork, and then properly disposing of everything. If you've never done this before, you should realize that it can be a challenge to get things completely removed, including the flooring adhesive that may also have asbestos in it. And, you often need a permit ot undertake this. Here is some guidance from a State environmental agency on DIY: Asbestos containing flooring Sometimes the best approach is to not disturb it, but to simply nail down a thin subfloor and then put your new material directly on that.

I am thinking about using a shellac finish and sealer on this hardwood, which will be the floor for a kid's room. This Bullseye traditional finish and sealer product from Zinsser seems widely used and well liked: https://www.lowes.com/pd/Zinsser-Bulls-Eye-Clear-Shellac-Actual-Net-Contents-32-fl-oz/3449840 This particular product says it is clear, and I think there is an amber tinted version. Can shellac be applied without problems to hardwood? I believe I could put poly on top of the shellac and be done. Is this right? Any tips or warnings? There is also this Sealcoat by Zinsser, which does not appear to be shellac based. https://www.amazon.com/Rust-Oleum-Zinsser-854-Sealcoat-Universal/dp/B000C02BXW/ref=sr_1_3_mod_primary_new?dchild=1&keywords=zinsser+shellac+sealer&qid=1610393849&sbo=RZvfv%2F%2FHxDF%2BO5021pAnSA%3D%3D&sr=8-3 Would the Sealcoat be a better option to just put over the hardwood? I have read elsewhere that shellac can be applied over poly, which is good since I don't know what is on the existing floor. Other places say shellac could be sanded after application, so when we have a chance to completely sand and refinish this floor, I would probably want to do this. Does this sound like an acceptable temporary fix, or is there something I should consider before proceeding? Would shellac ruin or damage the hardwood. I am also thinking about LVP, but I am concerned this hardwood floor is not flat enough for that. I understand the subfloor for LVP must be 3/16" within about a 1 foot diameter to work. Any ideas about this? Is there a way eyeball this floor to determine whether click LVP could be put down? Thanks!