Kitchen sheet vinyl floor replacement involves repair of damaged underlayment. Old dishwasher leaked, allowing water to wick into (and swell) original 3/8" particable board underlayment along front of adjacent cabinets and about 3 feet into center of room. DW has been replaced and floor is now completely dry, though wood is stained and vinyl has bubbled in those areas. What's the best way to replace damaged subfloor (to achieve level for new flooring) without ripping up entire room - especially damaged area under existing adjacent cabinets? PS: I plan to check old flooring for asbestos before proceeding.

 

is it just 1 layer of vinyl that is now existing?
if it is, you could just tear out bad underlay and vinyl (if no asbestos) and lay new underlayment, and level the vinyl and new underlay with a leveler untill its all smooth and flat. then lay a new sheet of vinyl over the top of it all.
But I am such a big fan of Plywood, I would actually recommend complete tearup of particle board and install plywood.
or you could get some 1/4 plywood to install ontop of it all (after bad underlay removed and new put in.
does that make sense?

 

Part of the problem is that some of the damaged underlayment is under the base cabinets (cabinets were set after underlayment was installed in room). so, to remove and replace all underlayment with plywood would involve removing and re-installing cabinets (and countertop). Too much work. Thinking about replacing damaged underlayment (except that portion located under cabinets) with 3/8" plywood, and scraping off all old vinyl (if not asbestos) on the "good" particle board to get level surface throughout.

 

the only problem with that may be that scrapping up is a pain in the behind, and it may create a ton of work, especially if the adhesive was really good. Alot of the vinyl may come up but leaves the backing, then in the process of scrapping, you will get alot of the underlay up right with it, then you will need to patch the floor, then install new vinyl if the area is totally level. Whew! lots of work, but it can be done. I would just ask that if the underlay under the cabinets are bad, do you need to replace it?

btw - its nice to see another Alaskan drifting around these parts.

 

From your description it doesn't sound like the old particle board is in that bad shape, why not simply lay a new subfloor (1/4 or 3/8 plywood) over top of the existing vinyl then lay new finish floor over that? Should be a lot easier than tearing out the old stuff and no worries about asbestos.

 

Unfortunately, the old underlay IS in bad shape for about a 5'x4' area around the front of the dishwasher. All swelled up and disintegrating. So will have to pull at least that part up. The rest should be okay. Only problem will be getting level with orig vinyl surface if I can't scrape that off. Maybe "feather" that off and use 1/4" plywood (or some new product I heard about that is very thin and has screw holes predrilled - anybody heard of that?) over all.

 

I just use 1/4 multiply over existing.

 

You can probably use a circular saw with the depth set to 7/16 to cut out the damaged area. Consider buying a few cheap peel & stick tiles to help match the depth. Thicker underlay (i.e. 3/8 or 1/2 inch) will help mask any variations in thickness. The downside is that thicker plywood costs more and you lose headroom.