Concrete floor sealer

[Nick Grant]

A friend has had a concrete floor poured in a pottery workshop and asked me about sealers. She says it it dusty and absorbent. My experience is with polished concrete but I don't know what to advise for this.

Would like to avoid solvents and other nasties if possible but practicality important as is a workshop.

Thanks

Nick

[Christopher Axon]

Hi Nick,

Firstly, I don't have a solution to your query but will keep watching as the reply would certainly interest me.

I've found a few references in the forum from you concerning the use of polished concrete floors, and am hoping you might share your experiences. I have a project on a very tight budget, and have been looking into using some form a polished concrete as a thermal mass. Unfortunately the professional stuff is very expensive. This would be used in a bedroom and bathroom environment, with wet under floor heating.  Any suggestions or advice would be greatly appreciated. The project is in Herefordshire.

BTW I've been lurking for ages following this forum, you guys are an amazing source of information.

Chris

[Nick Grant]

Chris

Yes, polished I have done!

Do you live far away?

We just used local readymix which we powerfloated. The hired a floor grinder and finished with water based wax sold for stone bathrooms.

Perhaps out of ignorance I'd put the UFH pipes direct in slab rather than screed. Avoid fibres as makes polishing impossible.

Nick

[Christopher Axon]

Sorry for the delay in replying, was on site last week.

I live in London but am up visiting site fairly often, which is near Great Malvern. So about 45min from you.

Was the mix a standard mass concrete / foundation type? I assume you were you happy with the end result? 

[Nick Grant]

Can't remember the spec but is a reinforced structural slab. Very happy with the result.

[Jean-Marc Bouvier]

Have you considered boiled linseed oil?

[Nick Grant]

Interesting idea but it's a friend's floor and she is some way away so I have not seen it. I'm wary of suggesting anything too experimental as it is a pottery workshop and it needs to be practical. I'd worry that using oil might prevent something else sticking if it didn't work.

After some tried and tested product!!

She may have sorted it by now but useful to know for others.

Nick

[Jean-Marc Bouvier]

Its far from being experimental. But good luck in your search

[Nick Grant]

Sorry when I saw 'have you tried' I assumed you meant as an experiment. So have you tried it? Could you recommend it? I did hear of someone using it on an earth floor near here but think it took them a long time to do because of drying between coats.

[Jean-Marc Bouvier]

I've used it on both concrete and wood. On concrete I used a mix of 1:1 of boiled linseed oil and mineral spirits in 2 coats. It will darken the floor thou.

[Christopher Axon]

Thanks for the info Nick, now all I need to do is get the client to sign up to the idea...

Chris

[mike whitfield]

The earth floor Nick mentioned had 10+ coats of oil and white spirit 50/50 I think (owner did it himself). The oiling seemed good, but was onto a fairly brittle background and couldn't be expected to harden the floor that much. But if it was onto concrete, I would say it would be ok, certainly worth a test patch eg in the doorway? It would darken it a lot though as mentioned. I would blow off the floor with a compressor and vacuum together a few times to get rid of the dust (make a big cardboard extension for the end of the vacuum and blast the dust up towards it).
I have used os hard wax oil on flagstones and terra cotta tiles to avoid the toxic stuff. It's supposed to be for wood but 2 coats lasted 8 yrs on the terra cotta tiles before we cleaned vigourously and prob scrubbed it off them recently............ I haven't found any 'organic' purpose made floor sealers for conc and tiles.
Mike

[Nick Grant]

Thanks Mike

We use OS hardwax on polished concrete in bedroom and it gave a darker slightly leathery finish compared with the stone wax in rest of house.

[Tahir]

Jean-Marc, why boiled instead of unboiled? And what does it do to wood flooring? We're going to be using end grain blocks

[Jean-Marc Bouvier]

Tahir
I will direct you to the following site that can do a much better job of explaining linseed oil better than myself. But from past experience, light, thin and multiple coats is best. A wax finish on an interior floor if so desired is possible. But remember it will be a more labour intensive process but the end results are good and peace of mind achieved. I remember hearing an "old wives tale" with regards to the application of linseed oil: "Once a day for a week, once a week for a month, once a month for a year and once a year for life"