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Question:

1) Chemically stripping will be too expensive and time consuming.

2) The original floors are thick oak floors and won't be damaged by another sanding as this is the first time they've been redone since the house was built in 1950.

3) Our contractor is more comfortable with sanding out the coats rather than chemically stripping.

4) No one is living in the house.................

My contractor is recommending a water based polyurethane so it will dry faster. Is there anything I need to know before he starts this process? Does it have the same drying capabilities as oil based poly, Is the same 70 F degrees recommended? Can a water based polyurethane work with regular stain or does it need a special stain? He's recommending two coats of the polyurethane this time so it will dry better, your opinion?................

Rich

Answer:



Dear Rich

Sorry about the delay in responding this time to your further inquiry, I was on a two week fishing trip. A major problem like yours is never solved by just a few emails.

Anyway the reason I still suggest chemically stripping, is that the floor finish is still soft. Your contractor may find that the floor sanding paper will clog up too fast to make any real progress on the floor. Or he will have to use very heavy grit sandpaper to remove this gooey finish. This stuff heats up under the speed and pressure of the drum and can be a bear to remove. If sanding has to be the option you might wait a bit more time to let the finish harden a bit more. Every, very coarse sanding, does remove about 1/6 of the total life of the floor.

If no dry more time is available, consider only doing a rough chemical strip using the fairly cheap to use Circa 1850 stripper. Or any stripper that has acetone, toluene and methanol (ATM) in it. It works quite fast and cheaply on poly finishes, but is a health hazard and quite flammable. Pour this stuff on and get out of the house, and ventilate. When the finish is fully blistered, it will then become easy to sand or scrape off. Thus avoiding that really coarse sanding operation.

But either way once you have removed all the old finish, this time use a fast dry wiping stain. There is now one available nationally called Bona Kemi Dri Fast stain. Visit their web site at http://www.bonakemi.com/productspecs/drifast_stain_spec.html

I think they are having a sale on this particular brand of stain until the end of August. I've used a local brand of fast dry pigmented wiping stains for years, and although a little tricky to use, they always dry overnight in even the darkest colors. Oh, ya, even let this stuff (Bona's) dry overnight. The manufactures are way too optimistic, and don't take high heat and humidity in consideration when making up those label instructions.

And while you're at it your could try their most excellent and durable Traffic finish. If you truly need a durable fast dry finish this is certainly one to use. But unfortunately water based finishes tend to turn somewhat opaque after about 5-10 years. And most folks have either moved, or now have to resand the floor. It depends how much light the floor is exposed to. That's why I stopped using water based finishes, and still stick to the good ol' oil modified polyurethane over my stain. I don't want a dark floor turning opaque after a decade. I also don't like the pale bluish white color of the water based finish film. I'll send you a pic to help illustrate this. This is a photo of a newly completed floor. This a very subtle problem, and is difficult to capture on film. But if pointed out, most people see the problem. You might ask the retailer of Bona Kemi in your area, to see some jobs that are more that 10 years old, before you jump at using ANY water based finishes. They are not a panacea they are made out to be.

So, in answer of your last question, yes stick to the stain and finish combo by Bona Kemi, accept NO substitutes. This company has at least done their adhesion and drying tests with these products. Traffic is generally applied in two or three coats over top of the dried stain. You can use any of the Bona Kemi finishes over this stain, including their own oil polyurethane. It generally takes three coats of water based to equal the build of two coats of oil poly. But their is no doubt that Traffic is the more durable. (but less appealing in my opinion) of the two types of finishes. You can apply up to two coats of water based finish in one day. But do make sure you have a flooring contractor who is very skilled at this rather tricky to use finish. Even water based finishes can be affected by the weather. Keep the AC going and ventilate just the same in either case.

Good Luck.

You may also find these articles helpful:

1. How To Chemically Strip Wood Floors without dust!

2. Floor Types And Finishes

3. How To Apply Oil Based Polyurethane WITHOUT The Pits And Bubbles

4. Custom Staining Wood Floors Without The Blotchy Effect

5. How To Take Care Of Your Health And Safety when Installing, Finishing, Repairing or Cleaning your wood floors