Protection Product for OSB Floor Please

[Russet Grange]

Hello all.

Just building my summer house and I'd like a recommendation for waterproofing/protecting the floor. It will be made from 18mm OSB. I doubt I'll be putting any further flooring over it, so the finish needs to look OK.

I don't mind a different product underneath, so maybe some kind of bitumen paint for below and then yacht varnish on top?

Thanks all.

[OutInTheShed]

I'd suggest a water based polyurethane floor varnish.
Tough and easy to touch up scratches etc.
If the floor gets direct sunlight, e.g. by a french door, a UV resistant/filtering varnish is a good idea.


The edges of boards need most protection, particularly cut edges.

Not sure about the bottom face, it needs ventilation, and a damp proof layer below it.

[JoshSm]

I'd probably think more of an oil based varnish thinned down for the first coats to get it to soak in. Main downside is the much slower drying times.

Oil ones have the durability, water ones tend to be clearer. For this I'd suspect durability is more important.

For a floor use a proper hard flooring varnish not just what comes off the shelf first.


When coating don't forget the edges. They'll be thirsty.

[Russet Grange]

Thanks both, and yes, very much noted about the edges.

[Nico Adie]

https://bedec.co.uk/product/floor-paint/