Floor: varnish over danish oil?

[Martin Pentreath]

I have a sanded wooden floor in a bedroom which I originally treated only with danish oil. I like the mellow matt effect which this gives, but the room is going to be changed to use as a living room, and the floor will start to get more wear which I don't think the oil alone will withstand. Is it OK to varnish over the oil? In other heavy-use rooms I've used "diamond hard" floor varnish (by Ronseal as I recall) which is water-based. Can you put a water-based varnish over a floor treated with oil or should I find some oil-based varnish?

[David Lang]

Hi Martin

Depends entirely if you have sanded the floor enough, but the short answer is no, it won't stick. If you are convinced you have removed the oil by deep enough sanding, a scrub with white spirit/steel wool should remove the remainder. You would then have to try a small area.

You could use an oleo resinous seal such as Bourne Seal. Very durable, takes ages to dry.

Dave

[Owain]

Danish Oil is fairly hardwearing. If you get worn patches just re-apply the stuff, or use a rug or two on the main wear points. I'd at least see how it lasts before doing all the work of stripping off the old to apply something new.

Owain

[doozer]

I would be surprised if Danish Oil wasn't hard wearing enough as it is pretty tough stuff. Give it an extra coat before the change of use and then just touch up any areas that need it over time. After all it's really easy to apply.

I doubt water based varnish will stick to Danish Oil as it's an oil. A good sanding might provide enough of a key but I would be surprised if the varnish would still flaked off in places. If you really want to varnish it I would sand it thoroughly and then use copious quantities of white spirit to try and get the last of it off.

[Peter Parry]

I've varnished over Linseed, Tung and Danish oil finishes with solvent based varnishes and had no problems at all after 4-8 years (the range of times the varnish has been down, 4 years for the Linseed oil finish and about 8 for the other two.)

[RichardS]

You should be OK with an oil-based finish. My bedroom floor was finished with 3 coats Danish Oil (one with a stain) and 2 coats of a Rustins oil-based satin finish. This was after consultation with Rustins' technical department. They said water-based varnish was definitely NOT ok, and would probably result in a milky "bloom" in the finish.

However, this was for application of oil & varnish in close succession (minimum recoat times). They did say that the likelihood of the bloom would reduce with time.

Your best bet is to contact the technical dept of your preferred finish & ask them.

The finish is OK - visually it's exactly what I wanted, but wear-wise it wouldn;t IMHO be up to primary living space usage.

The water-based diamond-hard type stuff that I used (blackfriars IIRC) for the office floor seems an order of magnitude tougher at least, but then it's going onto a pretty hard oak floor rather than sanded Victorian pine boards, so that may make a big difference.

[Biff]

Oil-based varnishes certainly stick to timber previously treated with linseed or tung oil (or Danish, which is mostly tung plus driers). But varnish does not look so good to some folk's tastes. Have you thought of the products from Osmo, particularly Osmo Polyx-Oil. Check out

You get a more natural wood kind of finish.