Bathroom tiling - adhesive, grout and substrate advice

[scoletti]

Newbie here...first post.

I'm about to start a bathroom renovation....it's not DIY, i'm getting trades in, hopefully to achieve a better and long lasting finish without leaks.

It's just a first floor 6m² bathroom.

Floor build up currently consists of floorboards nailed to joists. The floor is a little uneven and sloping – about 35mm off.

Walls are all brick which are plastered.

The job requires all walls and floor tiling – 30m² in all.

Every tiler i have 'interviewed' for the job has given me different advice and recommendations on adhesives, grouts and substrates.

FLOOR:

What method do you advise to level the floor? WBP Plywood or tile backer board such as hardiebacker, wedi or other? And what adhesive should i use?

WALLS:

Some of the walls are currently painted, others around the bath are tiled. When i take the tiles off the wall, some of the plaster may come off with it. The walls are not square and true. So what would be the best way to square up the walls ready for tiling? Board or bond plaster? And what would be the best adhesive/primer to use?

I am thinking of using Mapei Kerapoxy grout for both walls and floor.

I need a reasonably economical solution.

I am also thinking of using a tanking kit such as Aquaseal around the bath area for peace of mind.

BTW would you use a bath seal UPSTAND strip to seal around a bath?
http://www.ebay.co.uk/itm/130578697911? ... 1438.l2649

Thanks in advance.

[DTWCeramics]

Big post

The reason tilers will tell you different products, as it is either their brand they are used to, or the brand a local supplier stocks, that they can try and make a few pennies on.

DEFINATELY tank the area around the bath using a roll/paint on membrane, I.E Aquaseal, Ardex WPC - Alternatively you could install Schluter-KERDI waterproofing membrane on the wall, a 1mm thick, bright orange fleece membrane for waterproofing.

I am not sure why you would want epoxy grout in a household bathroom, epoxy grout is normally used in commercial kitchens! Get any grout with microbial hygeine built into the grout, such as Granfix Maxigrout.

For the walls that may be damaged, definately re-skim these with plaster and prime before tiling.

Levelling the floor, I would use a latex self-leveller such as the Arditex NA, a 2 part latex based compound, used in many different applications. Goes down like a dream onto nearly any surface, can be built up to 30mm in one layer (with granite chipping aggregate)

For adhesive, I always say hands down, Ardex. On the plaster walls, use Ardex D15 for your tiles (nice and cheap per tub, around £12 to trade) with Ardex P51 primed walls (bright blue!)

For the floors, if you do self level as I say, any flexible adhesive I.E Ardex X7R, or X77W if you're using natural stone.

Another point that has not been mentioned, is are you using underfloor heating? If so, a lot of my answers above will be irrelevant!

Hope this info has helped you.

Cheers

[Colour Republic]

I'd say the reason you have been given different advice is that some tilers know what they are talking about and others don't!!

First question before anything... What tiles inc size of them are you using? And what is the floor made up of currently? This would change every aspect of the products and materials you use.

[scoletti]

I'd say the reason you have been given different advice is that some tilers know what they are talking about and others don't!!

First question before anything... What tiles inc size of them are you using? And what is the floor made up of currently? This would change every aspect of the products and materials you use.

I just want to make sure that i've got the specification correct, to eliminate as much as possible any failures down the line when the trades have gone!

The tiles are 333x333mm, and are glazed procelain tiles.

Floor build up currently consists of floorboards nailed to joists. The floor is a little uneven and sloping – about 35mm off.

[scoletti]

Big post

The reason tilers will tell you different products, as it is either their brand they are used to, or the brand a local supplier stocks, that they can try and make a few pennies on.

DEFINATELY tank the area around the bath using a roll/paint on membrane, I.E Aquaseal, Ardex WPC - Alternatively you could install Schluter-KERDI waterproofing membrane on the wall, a 1mm thick, bright orange fleece membrane for waterproofing.

I am not sure why you would want epoxy grout in a household bathroom, epoxy grout is normally used in commercial kitchens! Get any grout with microbial hygeine built into the grout, such as Granfix Maxigrout.

For the walls that may be damaged, definately re-skim these with plaster and prime before tiling.

Levelling the floor, I would use a latex self-leveller such as the Arditex NA, a 2 part latex based compound, used in many different applications. Goes down like a dream onto nearly any surface, can be built up to 30mm in one layer (with granite chipping aggregate)

For adhesive, I always say hands down, Ardex. On the plaster walls, use Ardex D15 for your tiles (nice and cheap per tub, around £12 to trade) with Ardex P51 primed walls (bright blue!)

For the floors, if you do self level as I say, any flexible adhesive I.E Ardex X7R, or X77W if you're using natural stone.

Another point that has not been mentioned, is are you using underfloor heating? If so, a lot of my answers above will be irrelevant!

Hope this info has helped you.

Cheers

Thansk for the reply Matt.

Once the tiles are off....If the walls require patching up with bonding plaster is that sufficient background to tile on once it's primed? Or does the wall have to be skimmed for tiling?

The reason i'm opting for an epoxy grout is that it's more robust and waterproof. I know it's over speccing, but i dont want to skimp on the grout, i want to avoid it discolouring and allowing water through to beneath the tiles.

I'm not thinking of having any underfloor heating.

[Colour Republic]

ok...

firstly adhesive for the walls. You are just over the size for dispersion adhesive (ready mixed adhesive that comes in a tub) and seeing as they are porcs you would need a flexible cement based adhesive (doesn't need to be flexible but I always prefer it). The brand is really not massively important as that would be down to what the tiler is happy using, but some are better than others, there are too many to list but mapei, bal, weber.... are all good addys. You can use an sbr primer but I would use the same brand of primer as the adhesive.

Same for grout use a decent brand with anti-bacterial agent and flexible. You could go down the epoxy route but unless you were creating a wet room I wouldn't go to the expense and if you plan on doing this yourself then practice like mad with epoxy before you let yourself loose on the walls/floor.

As for the walls then unless the tiles are very thick you'll be alright with regards to weight issues on skimmed plaster, so you could tile straight over but tile backer boards, or tanking is an option and would be better. If you have the walls leveled up again with plaster then don't tile straight on to bonding as it is not recommened, so get it skimmed with finish plaster after.

35mm over 2.4m is quite a drop. If I was doing i'd take the old floor up and level it up that way, eith planting extra joists on to the originals or packing out. Then 18mm ply directly on to joist (screwed not nailed), then 6mm tile backer boards on top of that (You can tile straight on to ply but a lot of it is of poor quality these days and i'm less trusting of it now unless you can trace its source.)
Flexible rapid set addy for the floor, and again flexible grout.

oh as for those bath seals I hate them with a passion and they leak worse than a decently fitted bath. Tile and grout the bathroom but leave all internal wall corners and above the bath free of grout, then silicone these expansion joints with a silicone (if you have a coloured grout then most brands will do a matching silcone. (fill the bath with water just before you silcone and leave it full for 24 hours before draining)

[scoletti]

Thank you for your post Colour Republic, very informative.