One Pot Poly

I think the screwfix item is water rather than spirit based. You need to find one that says thin (or clean brush) with white spirit rather than water.

If Screwfix does not have an alternative, I am sure you will find one at B&Q.
 
Rustins Data sheets specify interior use only and to avoid sunlight. Probably a low resistance to UV either in the material itself or the dyes used for colouration. The data sheets specify keeping it out of direct sunlight.

'Exterior' grades will have better UV stability.
 
Maybe I got it wrong.

The last tin I bought at Screwfix (which was to varnish the hall floor) certainly was water based.

If it says spirit based and exterior grade, I would use it. After all it can be re-coated pretty easily if it start peeling.
 
I tried le tonkinoise varnish, ten coats on bare prepped teak, it failed after a year, I tried ten coats of International, it failed after a year, I'm now going to woodstains for my rails in the hope that whilst it may not look as good it will at least stay the course. it either that or sew covers for everything.:(:(
 
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