Tiling Bathroom

[Seanie_230]

Hello All
i want to tile my bathroom around my sash window architrave to make a start.
do i need to skim the wall or can i just tile directly onto the old render that is there?
one day a extractor fan will need to be fitted also?

what is the best thing to do for the external wall.

thanks all

 

[Zebra]

Re the extractor fan, it will be necessary to cut a hole through the wall using an appropriately sized masonry hole cutter, being aware that this can loosen the brickwork around the hole and lead to more repairs than you expect. You would need to insert a piece of solid ducting and mortar it in with a slight fall to the outside. It would also be necessary to have the wiring to the fan installed and plastered over, emerging from the wall at the location which the fan you have chosen requires it to.
All this BEFORE TILING.
That is, unless you want the wiring surface mounted, which I doubt you would.
Tile neatly up to the edge of the ducting.
Be aware when choosing a location for the hole that windows have lintels, and it's not good to cut into them. Be aware also that there are "zones" in bathrooms which dictate which electrical equipment can go where, and that anything in "zone 1" ie above the bath or shower, has to be 12 volts which means that you have to have a transformer outside the room, normally in the loft above. Be aware that wiring regulations also require fans to have an isolation switch outside the room, and an appropriately sized fuse as required by manufacturers instructions (a bit of a nuisance that regulation in my opinion!).
Any wiring in a bathroom also has to be notified under Part P of the Building Regs which means that either you have to have a Part P registered spark to do it, or you have to put in a notice to Building Control if you want to do it yourself.
As to your other point, I suppose it depends what the old render is that you have. My understanding is that you have to skim a wall before you tile. You may get better advice on that point on a forum more oriented to modern build. I often use DIYnot.com, but there are others.

 

[Flyfisher]

Extractor fan kits are also available with ducting to enable a fan grille to be fitted somewhere in the bathroom (typically the ceiling) and the outlet to be placed somwhere else convenient. The fan unit itself is then located outside the bathroom so that the electrical installation requirements are a bit less onerous as it is not located within the bathroom zone. But the final suitability will depend on the bathroom location and the internal layout - I just mention it as an option. For a fixed, in-wall, fan unit, then Zebra's post is the one to follow.

As for tiling onto the existing walls, I'm sure the tile adhesive will fix the tiles to the existing surface - the real question is whether the existing surface is adequately fixed to the actual wall. :wink:

 

[worms]

All this BEFORE TILING

Yes you want to have a full plan in place for all this so that the sequential stages work out

Extractor fan kits are also available with ducting to enable a fan grille to be fitted somewhere in the bathroom (typically the ceiling) and the outlet to be placed somwhere else convenient. The fan unit itself is then located outside the bathroom so that the electrical installation requirements are a bit less onerous as it is not located within the bathroom zone. But the final suitability will depend on the bathroom location and the internal layout - I just mention it as an option. For a fixed, in-wall, fan unit, then Zebra's post is the one to follow.

My thoughts exactly!

As for tiling onto the existing walls, I'm sure the tile adhesive will fix the tiles to the existing surface - the real question is whether the existing surface is adequately fixed to the actual wall. :wink:

And whether the surface is flat enough! It needs to be pretty flat to tile on to!

 

[Zebra]

Yes Flyfisher's suggestion is an option but one thing to consider if you were to duct through a loft space is that if the loft space is considerably colder than the bathroom, as it usually is, then the moisture can condense in the ducting and either drip back down into the bathroom, or leave you with a tube full of water in the loft! Therefore if you do it this way, insulate the ducting as well as you can!

 

[johnobirches]

Hi Seanie_230

No you don't need to skim before tiling but having said that a REALLY rough lumpy surface won't help you. Gouges and holes in the surface are ok but bit's that stick out are a problem.
If you get a straight edge and pull it over the surface you want to tile it will give you an idea of how the tiles will sit.
A lot depends on the size of the tile. A gently bowing wall can be tiled over with smaller tiles but the large modern format tiles can be a real problem if theres the slightest undulation in the wall line.

Check especially around the corners of window openings as the plaster at the corner can be very much higher that the plaster say six inches away from the corner which gives you a real problem in fixing that 'L' shaped tile you have to cut to go around the corner.

Whether you use ready mixed bucket adhesive or bagged powder adhesive, seal the wall with a sealer you get from the tile shop - this dries very quickly and stops the plaster sucking the moisture out of the adhesive before it has a chance to bond to the tile.

This all produces a non breathable wall of course!
John

 

[MdB]

Note that waterproof tile adhesive means that the adhesive is proof against water and won't degrade whilst wet. It doesn't mean that it will stop moisture moving through it. (at least this is my understanding which may be wrong)

 

[johnobirches]

Tile adhesive that comes in bags is cementitious - made from cement. Not sure about the ready mixed bucket adhesive.
Of course the tile itself, being glazed, won't pass any moisture which leaves the grout line. In a bathroom I would use a water resistant or water proof grout.
Hence I would regard a tiled wall in a bathroom as non breathable.
Not trying to be contradictory MdB - just explaining my reasoning.
John

 

[Seanie_230]

Hi all
Thanks for the great advice. I will get a extractor fitted before I do anything to be safe rather than sorry.
After that I will get a skim on a wall or two so I can get started and do at least one or two walls.
Good thing is it does not need to be a perfect skim just a flat secure wall.

 

[Keithj]

I made the mistake of trying to tile direct to the wavy wall in the bathroom of our C18th former pub in North Wales. The result looked 'orrible.

The local hardware shop suggested the fix (for the kitchen) which was to tack hardboard to the wall, and tile to that. It sits on the bumps and provides a reasonably flat surface. Not a solution for the purist, but it did the job for us.

 

[Flyfisher]

Yes Flyfisher's suggestion is an option but one thing to consider if you were to duct through a loft space is that if the loft space is considerably colder than the bathroom, as it usually is, then the moisture can condense in the ducting and either drip back down into the bathroom, or leave you with a tube full of water in the loft! Therefore if you do it this way, insulate the ducting as well as you can!

Good point. I hadn't thought of that but it seems obvious now you've mentioned it.

 

[Flyfisher]

Note that waterproof tile adhesive means that the adhesive is proof against water and won't degrade whilst wet. It doesn't mean that it will stop moisture moving through it. (at least this is my understanding which may be wrong)

My understanding as well. This why waterproofing kits are available for building shower cubicles and similar - you can't rely on the grout/adhesive preventing water from reaching the wall.

 

[Flyfisher]

The local hardware shop suggested the fix (for the kitchen) which was to tack hardboard to the wall, and tile to that. It sits on the bumps and provides a reasonably flat surface. Not a solution for the purist, but it did the job for us.

How long did the tiles remain on the hardboard?

Everything I've read about building shower cubicles suggests a minimum of 18mm plywood fixed at 10-inch centres onto a rigid frame or wall in order to provide a fixing surface that won't flex and cause the tiles to detach. Actually, these days even plywood is not recommended as dimensionally-stable 'tilebacker' boards seem to be the current state-of-the-art.

Perhaps hardboard might perform adequately in a kitchen environment but I'd have my doubts about it being a long-term solution.

 

[johnobirches]

MdB wrote:
Note that waterproof tile adhesive means that the adhesive is proof against water and won't degrade whilst wet. It doesn't mean that it will stop moisture moving through it. (at least this is my understanding which may be wrong)


My understanding as well. This why waterproofing kits are available for building shower cubicles and similar - you can't rely on the grout/adhesive preventing water from reaching the wall.

Flyfisher wrote the second bit but I don't know how to do nested quotes yet.

I don't disagree with this but just because water can get behind the tiles it would be a mistake to call the wall breathable just bear that in mind if it's a solid wall. I've been a self employed tiler for 7 years now and i regularly get called out to "fix" a leaking shower cubicle [dripping from kitchen ceiling]. It's always a disaster with soggy plasterboard, rotten studding and tiles which have to come off and can't be matched with new ones.

If it was my shower I'd reinforce the studding and board out with 10mm tile backer board then use a tanking kit which tapes over joints in the boards and adds rubberised paint to the walls before tiling. You'd be surprised though how many new builds are going up with the showers tiled straight onto ordinary plasterboard.
John

 

[MdB]

I agree totally with you there John. I wouldn't call grout breathable - it just doesn't stop all moisture either even if it is "waterproof".

 

[Flyfisher]

Agreement here too. I was also thinking more about the waterproofing aspect of shower tiling.

I'm a bit paranoid about leaking shower cubicles. I finished building one earlier this year but I think it's probably a bit over-engineered for me to ever make a living out of such things, judging by how long it took me!

As johnobirches mentioned, I built a reinforced studded wall based on 4x2 timbers on a roughly one foot spacing both vertically and horizontally. I then screwed 18mm WBP ply to the frame. I used a shower tray with upstands positioned in line with the ply walls so that they extend up and behind the tiles and I used a Mapei waterproofing kit to prepare the walls before tiling. No signs of any leaks yet!

 

[Keithj]

The local hardware shop suggested the fix (for the kitchen) which was to tack hardboard to the wall, and tile to that. It sits on the bumps and provides a reasonably flat surface. Not a solution for the purist, but it did the job for us.

How long did the tiles remain on the hardboard?

In the kitchen: they were still there, as firm as ever, when we sold the place some years later. I think in a bathroom I'd have used something more rigid such as plywood.
I did try to remove the wavy tiles from the bathroom wall, but they weren't having any of it.

 

[AMc]

You'd be surprised though how many new builds are going up with the showers tiled straight onto ordinary plasterboard.

Erm guessing almost all of them? We had a flat in a school conversion - first residential occupants - the first time I cleaned the tiles above the bath I rinsed them with the showerhead from the mixer taps. There was a horrendous cracking noise and half the wall came loose. I discovered they'd been dabbed onto the wall with 4 spots of adhesive and only the grout was now holding the whole sheet in place. It was our first flat and I had no idea about DIY but now I think back it was definitely standard plasterboard behind there, I just bought a big tub of ready mix adhesive and spent the next few hours swearing mightly as I gunked them back in place. It didn't fall down in the 2 years we were there but I bet it has by now

 

[wobs]

The ready mixed adhesive is suitable for smaller tiles (less than 200mm*200mm). With larger tiles you should use the bagged powder. Another situation you should use the bagged powder stuff is on cement render, although I doubt people here have such a surface to tile onto. This is all to do with the chemistry of how each adhesive type dries.

Surfaces should be primed with an acrylic primer (a blue liquid). Do not use PVA, as any moisture will turn it to mush and your tiles will fall off.

I also used a waterproofing system for our shower - The BAL WP1. Not cheap, but did the job.

As flyfisher said, there is no harm in a bit of paranoia with regard to preventing leaks. Make sure everything is solid, flat and water tight. Any movement of the tiles (or bath/shower) in the future could cause problems.