Floor varnish changing colour of floorboards

You need the Diamond Hard with the colour tint in it, or you need to stain prior to varnishing. Clear diamond hard will not change the colour significantly, nor will any other clear varnish.

IME most clear varnishes will darken the wood slightly. They may or may not be enough for the effect you seek.

Stay away from tinted varnishes, as the floor wears normally the varnish chips, and light marks on dark wood look awful.

Stain might get you what you want, but I prefer to leave them pale initially and let them darken naturally. It doesnt take long to start looking good, and the result is much better imho

NT

I've found the water based ones don't produce that lovely mellow glow on pine you got with traditional varnish. But are better for woods you don't want to change the colour of.

OK, thanks. So what still available now, that you would class as "traditional" varnish?

Cheers Richard

Thanks. I just wish I could remember what I used last time. I'm pretty sure it was Ronseal, come to think of it. I guess I'll just sad a bit of gash floorboard from the works upstairs, and experiment.

Cheers Richard

Dunno - look on the tin for brush cleaning instructions. If it needs white spirit it will be oil based.

Any of the high VoC content jobbies, and not the quick drying type. (the latter are not as hard wearing)

Varnished pine certainly darkens considerably with oil based varnish. Could be a combination of the varnish and the wood itself changing colour. Doesn't seem anything like as dramatic with a water based varnish - perhaps this blocks out light etc in a different way?

What's puzzling is that none of the high VOC varnishes I've seen in the sheds are billed as floor varnishes - for example:

I'm puzzled that while the sheds continue to sell high VOC solvent based varnishes, the only ones they have that are explicitly floor varnishes are medium or low VOC water based varnishes. Makes no sense to me.

Regards Richard

I suppose that makes sense, when you think what happens when you apply oils to wood - not that I suppose the solvents used in varnishes bear much relation to linseed oil, teak oil, etc. ;-) and I suppose in theory the solvent is just a carrier, that evaporates.

Regards Richard

You could try the old ploy of spraying a mild alkali over the boards, this brings out that nice mellow colour in minutes. Half a teaspoon of caustic soda to a litre of water in a plant sprayer, mist it over, allow to dry. Works a treat.

I did that on some new timber shelves once - scrubbed them with caustic. It certainly took the hard edges off, and yellowed the wood. Looked OK once I'd gone over it with Fiddes, but nowhere near as nice as the pine frame of a mirror left on a sunny wall for a year...

Anyway, I have a plan now - I don't see why the Wickes matt high VOC polyeurethane varnish shouldn't be good enough for a floor, so I'm going to try that.

I've spent the past 20 mins reading the archive, and discovered admonitions to use gloss for the under-coats, if using matt for the top, to avoid a milky finish - I'm speculating that this applies to water-based varnish, though.

Suck it and see, I think.

Cheers Richard

Absolutely. Natural ageing beats staining etc every time. But I reckon the varnish does add to the colour - in the same way as oil based white paint doesn't stay white for long.

I have both.

Bill

Maybe one reason is that use on a floor can be overwhelming due to the high VOC. On more modest things the absolute amount will be lower.

Which is why the two pack acid cat floor varnishes don't seem to be generally available now. They have the advantage of being extremely tough and totally clear. For a mellow yellow look, I'd use a standard polyurethane, even if it's not specifically for floors. Water based varnishes are certainly clear in the sense that they don't change the colour, but they still have that cling film look, which I think is the nature of the acrylic beast. The harder the resin, the higher ambient temperature it requires to cure and remain clear, so d-i-y stuff is never going to have the toughness you can achieve in a controlled environment

Right, I'm back, with some test results and another question.

I've done two test pieces on spare board (that was taken up during renovations upstairs), one with Ronseal Diamond Hard Floor Varnish (water-borne polyeurethane, medium VOC), and the other with Wickes Professional Interior Varnish (solvent-borne polyeurethane, high VOC).

As predicted, the Ronseal lowered the colour ever so slightly without really changing it, but left a plasticky-looking finish that I don't like at all. The Wickes produced the lovely golden colour that I was after. However...

The management has decreed that the more natural colour obtained from the Ronseal is to be preferred. In fact, she's right, as it matches the natural wood colour of our stripped and waxed doors (the mellow golden colour worked in the previous house, because the doors themselves were a mellow golden colour, through the application of linseed oil, which is not the case here).

So I'm tempted to use the Ronseal as the first couple of coats, to seal the wood with a lighter colour, then to finish with a couple of coats of solvent-borne matt (or more likely satin), to avoid the plasticky finish. Does anyone know if there could be any problem with applying a solvent-borne varnish over a waterborne one, once the latter has dried? I can't immediately see that problems are likely - I know you have to be careful if doing it the other way round, to make sure the solvent has evaporated, but the water evaporates quite quickly. Could there be issues over the one bonding with the other?

Regards Richard

Probably won't be any immediate compatibility problems, but a hard varnish on top of a softer one isn't usually a good idea, especially on a floor. You may find that applying the Ronseal differently will change the look. Try brushing it on, then wiping with a rag after a few minutes as if you're trying to remove it. Repeat if necessary (when the first coat is dry), using a circular motion, until the rag starts to "drag". The plastic look is really to do with the thickness of film sitting on the surface, which I prefer to keep to a minimum.