A Whitewash Finish for Oak Flooring
Advice on a very tricky floor finish: bleaching the oak, tinting it white, and covering with a durable clear. August 14, 2007
Question
I work for a carpentry and construction company around London, England. I have a client who is looking for a matte whitewash finish for some oak flooring we've installed. We've tried traditional methods such as lye and soap, or tinted oil, which she didn't like. Basically I am looking for a product that seals the wood like a urethane, has a matte finish, and tints the wood white, while allowing the grain to show through un-mottled, does not tan over time, and is relatively easy to apply to large surface areas, allowing for buffing to a fine finish. I have experimented with stains and lacquer topcoats on furniture in the past, when I was a joiner, but need something less labour intensive to apply, seeing as it is for a large flooring application (200sq/m).
Forum Responses
(Finishing Forum)
From contributor D:
What did she not like? Was it the pickled effect of solid white in porous grain? Was the background oak tone overpowering the white? Did you bleach the oak lighter before trying pigmented oil? Did you try a clear grain fill prior to white pigmented oil? This will prevent porous grain from filling with white pigment. A water-based 2 component poly like SLC's Aqua Pur HPX will stay clear without yellowing over time and is fairly easy to apply with a roller or t-bar flooring applicator. Berger Seidel has a similar product.
Form the original questioner:
Basically it was that the background oak colour overpowered the pigment in the lye and the pigment in the soap finish. I thought about bleaching the wood, but due to the fact that you have to clean the wood with water quite a bit after applying hydrogen peroxide, I didn't think that this was very practical on a large wood floor. The grain filler option probably will not work as the floors have a slight chamfer along the edges to create a 'V' groove where the boards meet, and I would expect that they would only get filled with paste as well. Are you recommending that I use a tinted oil overlaid by a clear poly? Would that benefit from a coat of sanding sealer first?
From contributor D:
A dewaxed shellac sealer would guarantee adhesion but would amber the white. Wood Cote wood bleach is a mix of peroxide and sodium hydroxide that is mixed just prior to using and it is self neutralizing. Fairly easy to use on a floor. I have bleached 5000+ sq/ft of flooring this way in two days with two helpers. We would then apply a white tinted oil like Duraseal Penetrating Finish and allow several days dry time with good air movement prior to coating with waterbased poly (2 coats gloss and one matte) which gives a better iridescence than all coats in matte. The water in the bleach helps open the grain to more pigment and oil is absorbed. Plain water can have the same water popping effect, which will yield a stronger white when oiling. Be careful when intercoat abrading to not steal color. Don't expect to sand totally smooth until after the second gloss coat. After first coat, buff only with a maroon 3M Finishbrite pad well enough to allow for mechanical adhesion of second coat. You most likely will not remove all of the roughness from grain raise until after the second coat. This is a technically difficult finish and I wish you the best of luck!
From the original questioner:
Thanks, that sounds interesting. Seeing as the water in the bleach will raise the grain considerably, any recommendations on sanding procedure prior to the first coat of poly? Assuming that the floor starts off smooth enough to seal, prior to bleaching.
From contributor D:
You could burnish in the white oil with steel wool under a floor buffer. This will lighten the floor. For maximum white I would build coats of poly over the grain raise. This kills a little of the shimmer, iridescences, chatoyance, or whatever you call that third dimension or depth you get with fine finishes. I figure if your client was worried about that they wouldn't be looking to go white. I recommend abrading the first coat with a maroon floor pad on a buffer only enough to insure adhesion of second coat. Sand smooth with 320 screen after second coat until smooth. Do not expect to get all of the grain raise off with first inter coat abrasion.
