Hello all,
Apologise for being quiet for 4 months, but I was undertaking a lot of trials with wet room.
1. pouring water into basket - floor still wet after a week so potential issue with piping or shower faucet
2. not using shower for a week - floor still wet so potential issue with piping or shower faucet
3. put Silicon over grout in wet room - wet room dry, but grout outside wet room became wet so potential issue with piping or shower faucet
4. decided to open shower plate and reconnect all fixture - floor still wet so potential issue with piping or shower faucet
5. spotted couple water drops from shower valve, about 1 drop per minute - change valve cartridge for £25, but this didn't fix the issue, when I turn valve water drops were coming out.
6. decided to replace whole shower mixer unit, went for Vado due to design and 10 years guarantee - knock some bricks behind the bathroom, plumber to deinstall old and install a new mixer, then plaster, skimming and painting.
7. removed Silicon which I put over grout
8. removed epoxy grout from wet room floor - extremely hard/almost impossible. Luckily Silicon soften the grout and I managed to remove about 6 inches of slightly cracked grout.
9. 6 weeks on and voilà - floor outside wet room dried and there is no sign of any water penetration in wet room.
I hope it will stay like this forever now and epoxy won't crack after while (it didn't cracked at all at other side of wet room from time of wet room build so it should be fine)
Couple things to note:
1. tanking is a must - tanking paint became a layer of plastic foil which really stops water penetrating floor or wall
2. buy good shower mixer and do pressure test after installation when all pipes are still visible and easy to fix
3. epoxy grout - I've heard it's not for wood subfloor, but Porcelanosa advised me to buy that type of grout for my wood floor. Epoxy grout is really a pain to apply, but it seems to work. I am still curious why grout was wet when water was underneath the tiles, but since new mixer was installed then grout is dry and stop water going behind tiles?
Thank you, hope someone would find this helpful