John Stumbles wrote:
On Sun, 26 Apr 2009 10:41:59 +1200, Gib Bogle wrote:

We are planning to replace the tiling on the bathroom floor in our
house. The particle board floor has already suffered a bit of water
damage in one spot (this I have attended to with a two-pot epoxy sealer,
which has soaked right in and made that patch very strong) therefore I
intend to make sure that the whole surface is properly prepared before
laying the new tiles. I could use the two-pot treatment, but it would
turn out quite expensive. I'd be grateful for suggestions about the
most suitable type of product to use for this purpose. Thanks.

Ha'porth of tar :-)

Unless you're just slapping down some cheap tiles to tart up and sell the
place I'd really, *really* rip up the chipboard and put down at least WBP
ply to tile onto. Water *will* get past your tiles (or more to the point,
grout) and the chipboard *will* swell up and probably bugger up the tiling.


"Will", but when? This tile has been down for 35 years, and the damage
to the untreated chipboard is slight. I'm guessing that with a
waterproof treatment the floor will last a lot longer. Although it's
not cheap, using the sealer I referred to would cost much less than
replacing the flooring. This "Penetrating Epoxy Primer" is claimed "to
penetrate and saturate the timber" and to have "waterproofing qualities
suitable for marine use".