We have seen it many a time where poor workmanship has caused undue stress for the client but has to a large part payed our wages.
It also seem that tiling is one of those trades where many people are willing to “give it a go”,and this seems OK at first if it looks neat ,but behind the scenes and underneath the tiles often disaster waits!
If I was a homeowner hiring a tiler to do my bathroom this is what I would be looking out for.
If the tiler lays a plywood floor on top of floorboards or joists for the tiles. Go and jump on it.Literally jump up and down on it.If it seems bouncy your tiling will probably fail. In fact even if you are uncertain suggest that it feels bouncy and you want it stronger.(please see the video on the right for an idea of how a reasonably strong floor should be.)
They say that 18mm is the British standard and it should be adhered to but if levels are an issue and you need to loose a few mm on the plywood thickness there must be additional noggins put between the joists. If you are going on top of floorboards then again after the plywood is layed jump on it and feel for any signs of deflection or weakness.
Squeaking is also a bad sign as it suggests movement which could result from the screws not clamping the plywood securely to the joists. Make sure there are plenty of screws all over the floor every 9 inches.
Wall substrates fitted by the tiler must also have (plenty of screws) .You might be told that cement boards/Wedi boards are the new thing but if its going on a floor bend one of them first, and if you can bend or break it wont strengthen the floor. The new substrates are very good for walls though.
Tiles need to stick well. Tiles can only stick on a good backing. If the backing is weak then the tiles weight will pull it off the wall. So for example tiles being layed on plasterd & painted walls are only as strong as the paints adhesion to the plaster. Or the plasters adhesion to the wall. So paint should be removed or it must be strong. You can use a bit of Ducktape left for a few hours and if it pulls paint off then the paint will cause tiles to fail. You need to check the plaster with a scraper for adhesion to the wall and again knock all the walls feeling for movement or weakness.
Adhesion is greatly improved by a ” mechanical bond” which just means that the backing for the tiles is keyed. So when gravity pulls down on the tiles the adhesive is blended with the ripples in the background which means it does not just rely on the “glue effect” of the adhesive. Modern backing boards have this built in and therefore create a much stronger bond than plaster or plywood.
Tile Primer for surfaces.
The adhesion of the tile depends on the strength of the very top of whatever it going onto. So for example if you are going onto a beefy 21mm plywood but the very top of it is all dusty. Then the tiles will stick to the dust and will result in failure. So plywood surfaces and concrete need to be primed.Which basically just glues the top of the surface all together and makes it solid. PVA does not work in wet areas as it gets soft again so looses its adhesion. Often the sure mark of a professional tiler is the primer he uses. Proper primer usually is blue/blue-green in color. Primers are expensive and its so easy to just use PVA and be done with it. But if you see a professional primer being used you can relax a little because to me it says the tiler cares about your job.
You want to see the word flexible on everything being used. Flexible adhesives are more expensive and compensate for any movement that happens all the time in buildings. If adhesives are not flexible then the tiler is probably cutting on costs. Plywood floors wont last 6 months without flexible adhesive. If you really want to get technical look for CE ratings on the adhesive bags. These basically mean the adhesives have passed the required European tests for strength etc.
It amazes me when tilers don’t use waterproofing in showers etc because the tiling is guaranteed to fail! Water resistant plasterboard is not enough.There are waterproofing systems that all have a paintable rubber like liquid that forms a membrane.If these types of “membrane ststems” are not being used then the backing boards that the tiles are going onto must be a 100% water tight. Fiberglass boards like Wedi are good.
So in summary a tiling job is only worth 50 % of what it looks like and the other 50% is “what it is going on top of” and the quality of the materials etc. I have seen countless nice looking jobs that have failed after a year or two.
We offer tiling services and for bathroom fitters & installers, or wet room installation in London give us a call.
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