PS see here for why you should avoid tiling over the existing tiles – particularly if they are falling off the wall as in the picture above.
Use a bolster and chisel or an SDS hammer drill with a tile removal attachment to prise the old tiles off the wall – this is by far the quickest method.
Be sure to prise the tiles at an angle (don’t hit directly into the wall) as you could do some real damage if you happen to have very thin blockwork walls i.e. you may go all the way through the wall!
If you have a skip, I recommend using trugs to carry broken tiles to the skip (above).
If you’re bagging up rubbish to be removed at a later date smash up the removed tiles with a hammer into small pieces– you’ll fit more rubbish into each rubble sack and you’ll be less likely to split the bag.
This outcome allows for easy retiling with minimum preparation work.
As a result, you should not be charged any additional costs by your tiler or bathroom installer to prepare the walls for tiling, assuming he has priced to a) remove the tiles and b) tile the walls.
To remove remnants of old tile adhesive from the wall (essential to produce a flat surface onto which you can tile) use a hammer and old blunt wood chisel or wallpaper scraper.
Fill any large holes with bonding plaster, ensuring that you prime any surfaces with a diluted PVA mix 1st (see the back of the PVA tub for dilution quantities) to ensure good adhesion.
Small holes can be filled with a powdered filler.
Sometimes tiles are tiled onto render, and over time (many many years) this may come away from the wall behind.
‘Blown’ render is no longer effectively adhered to the brick / block wall behind, and is liable to fall off as pictured above.
Tapping on blown plaster or render produces a telltale hollow sound.
If you tile onto plaster or render that is not adhered to the wall behind, the extra weight of the tiles may cause all of the render to literally fall off the wall, taking your tiles with it and wrecking your bathroom.
Never take the risk.
Blown render has to be removed from the brick / blockwork behind, which can result in increased labour & disposal costs and time delays if this has not been accounted for.
Furthermore, these stripped back walls will also need to be re-boarded or re-rendered before tiling, and this will likely cost extra to the ‘strip & retile’ scenario mentioned above:
This is most common on plaster-boarded walls that have been tiled onto directly i.e. the plasterboard was not plastered (skimmed) prior to tiling.
Unfortunately, if this occurs, then all of the damaged boards will have to be removed and replaced, and they may also need skimming with finish plaster depending on whether you’re fully tiling the walls or not.
In the example below the old tiles were removed…
but they brought the walls down with them…
so the walls were re-boarded with (green) moisture resistant plasterboard via a process known as dot ‘n’ dabbing (essentially gluing the boards to the wall with a product called drywall adhesive)….
…..which gave a flat surface onto which tiles could be applied (after the walls were tanked).
to produce a nice finish….
In this instance plaster has been applied to wooden lats as opposed to a rendered solid wall or directly to plasterboard.
When the tiles are pulled from this surface they will probably pull the plaster off the lats as the tile adhesive sticks better to the plaster than the plaster does to the wooden lats.
If this occurs, I heavily recommend removing all the existing render & lats and reboarding all of the affected walls. This is because render does not stick very well to wooden lats and once the added weight of the tiles is added to the walls, it becomes increasingly likely that the tiles and render will be pulled off the lats and your walls will effectively fall down.
Removing the lats & then reboarding (above & below) is sometimes preferable to overboarding the wall (see comments below) as this technique will make the wall flatter and therefore easier to tile.
However, it will in all likelihood incur additional labour costs.
This is because lat & plaster walls are never flat due to their construction technique (as lats often overlap on studs for fixing.)
If your lat & plaster internal walls are flat and you want to tile them without stripping the wall back first (a messy, dusty job) you can overboard the walls (rather than strip them back to the studs as above).
i.e. sheets of plasterboard are screwed over the existing plaster, into the wall studs behind (not just the lats!)
This saves the time, mess and disposal costs associated with removing all of the existing plaster and all the lats (De-nailing lats takes a long time!)
If you are about to hire a contractor or tiler to do your bathroom (and part of his work is to strip the existing wall tiles and then re-tile) make sure you know what additional costs you may have to pay following the removal of the existing tiles (depending on the outcome!).
The last thing you want is to have an extra cost sprung on you at the end of the 1st days work (stripping out) if the contractor has not pre-warned you of any potential extra costs.
This would leave you in a very vulnerable negotiating position as a homeowner as you really have very little choice as to whether or not you have the reboarding / bonding work done before the work can proceed, as you will by now have a bomb-site for a bathroom and will no doubt be keen to get your facilities back up and running.
I ensure I always forewarn new customers about these potential costs, but I know MANY tradesmen that do not manage customer expectations in this way and it often leads to problems.
Anyway, I hope this helps.
PS If you live in Leeds and are looking for a bathroom installation team then please fill in the red contact form on this site and I’ll call you back!