Tiling FAQ

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Adhesive types

Powder or tub

Premixed tubs are convenient and more expensive, and don't store as well. Once opened they tend to set over a few days.

Dual purpose grout & adhesive

Products intended to do both do both poorly, as the requirements for both are different. Not recommended.

Water resistant

Water resistant adhesive is needed for shower and over bath use. More basic types fall off after a bit.

Sand and cement

3:1 sand and cement has long been used to lay tiles.

  • Very cheap
  • Strong & durable
  • Unaffected by water
  • The tiles must be soaked in water overnight.
  • The main downsides are the short open time and long cure time.
    • Only set out a smallish area at a time
    • Smooth the surface
    • Place tiles on promptly.
  • For floor tiles, keep foot traffic off for 3 days
  • Not a popular method any more, modern tile adhesives are easier to work with.


Epoxy grout is primarily for swimming pools. Its pricey. Durability is excellent.

Adhesive laying

Wall tiles on an even surface use a notched adhesive bed, applied with a notched edge. Plastic spreaders soon wear out, use a metal one.

Wall tiles on an uneven surface use 5 blobs of adhesive per tile. This gives much more adjustability. The end result isn't quite as abuseproof, as there are unsupported spaces behind the tile, but its not usually an issue.

Floor tiles require very solid support, large notches in the bed should be avoided. Blobs are no use with floor tiles, not enough support.

Grout types

Basic grouts aren't waterproof.

Tile adhesive can be used for grouting, but isn't ideal.


Grout is usually applied with a rubber edge. Push grout well into the joints, go over them repeatedly to get as much in as possible.

Use the rubber edge at 45 degrees to the grout lines to get a good final grout shape.

Its possible to grout small areas with a finger, but this leaves a rougher surface which isn't ideal.

When the grout is sufficiently set, clean the tiles a couple of times with a wet sponge to remove most of the film of grout on the tile face. Wring the sponge out in clean water repeatedly. If done too soon, the joint grout is affected. If done to late, the tiles don't clean up, and surface grout film then needs removing with a plastic scourer. Let dry, then polish the tiles with a dry cloth to remove the last of the film.

If its not cleaned up in time and sets fully, use a plastic scourer wet to clean off grout film.

Finally, lithofin & similar treatments make grout wipeable clean. This makes a big difference to long term appearance.

Grout reviving

First clean as well as possible then bleach. A plastic scourer can be used if scraping is necessary. If grout's in a weak condition it can pull out.

Grout reviver is just grout. Scrape the grout surface clean, and wipe on new grout with a finger. when set, clean the tile faces.

Tile size

Large tiles make cleaning a bit easier, but are a fair bit harder to get flat enough, they're much less tolerant of the slight misalignments usual when tiling. They can make small rooms look smaller.

Small tiles take longer to lay a given area, but are much more forgiving regarding alignment.

Beyond that its just a matter of taste.

Tile spacing

Plastic tile spacers work where the tiles are all precisely sized.

Where the tiles aren't precisely sized, which is fairly common, folded card is the best option. Anything else to hand can be used, but folded card is readily adjusted.

What spacing to use is largely a matter of taste. Usually the chosen gap is anywhere from a tight 2mm to a massive 10mm, more often 3mm or 4mm. Grout gets dirtier than the tiles, and is harder to clean.


Remove all unsound material, bulk dirt etc.

Most tiling is done direct onto the eisting surface, but sometimes sheet materials are used to provide a suitable surface. Hard cement faced polystyrene is sometimes used for floor insulation.

Layout styles

Normally tiles are laid square to the walls. Other styles include:

  • mosaic work
  • diagonal tiling
  • gaudi style tiling


Its normally best to centre the tiling rather than starting at one edge. The room centre can be the centre of one tile or the centre of 4, whichever avoids any thin strips around the edges.

Software can be used to see what the layout will look like and avoid a layout oops. Any softward that can plot a tiled imagine can be used, such as gimp, sketchup and many simple drawing apps. The repeated image is that of a tile plus 2 sides of grout.

If you run into a situation where you can't get an ok looking layout, another option is to put a tile border around the outer edge. This can be in a different tile size or mosaics, or even in a different colour of tile.

Order of work

Tile cutting

link to existing wiki article

Quantity estimating

If you're using a tilesaw, wastage should be negligible. You do of course need to allow a whole tile where part of one is used. Some cut tiles can be cut & used a second time, making total wastage near zero.

If you're using a score and snap cutter, wastage depends on ability to score and snap, and can be anywhere from 5% to 20%.

Cost cutting

Cement & sand makes a very cheap adhesive

Gaudi style tiling can be done with broken tiles

Used tiles can often be cleaned up and reused to tile a smaller area. Soaking them in water overnight turns a lot of adhesives to a soft state easily knocked off.

Its even possible to use stone chips in lieu of tiles, though it doesn't help cleanability.


There are 3 main ways to do external corners (eg the front of a window ledge)

Just tiles

The basic way to finish external corners is simply to use the tiles and nothing else, like so:

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If the tile biscuit colour matches the glaze, the edge biscuit can be left visible. If it doesn't, grout is applied to make it match the grout lines.

If the tiles aren't too bulky, the resulting joint looks much like another grout line. People's reactions to such joints vary, some people like them fine, some don't.

Plastic strip

Rounded plastic strip is popular and easy. Prone to becoming harder to keep clean than glazed tile after many years. Too often the plastic strip won't match the tile in colour.

Rounded edge tiles

Tiles with rounded over edges are available in some tile ranges. These work very well, but cost more than the usual tiles.

Pros and cons of tiles

Durability, robustness and longevity are tiles' main strengths. Cleanability and appearance are also good. UFH can make them comfortable with bare feet.

Tiles are one of the more expensive and time consuming surfaces to lay, and can be cracked & broken by abuse or a dropped cast iron pan.

Floor tiles can increase risk of injury from falls compared to softer floorcoverings like flexible vinyl.


A waterproof membrane is best practice under the tiling to prevent water penetration to woodwork, but few diyers use them.

Adhesive and grout must be water resistant.

Lithofin etc helps keep the grout clean

Rough surfaced tiles are harder to clean


Grout is best in corners not prone to movement, ie where masonry meets masonry, and no cracking has happened over time. Corners prone to any movement should use a flexible sealant.

  • Ms polymer lasts well but discolours a bit
  • Silicone goes black with mould after a while. Use mould resistant to delay this.

Plastic strip is usually used over sinks & baths. It sits behind tiles, with the flexible edge protruding and pressing against the bath or sink.

Tile buying

Wall tiles aren't suitable for floor use, they're too thin and slippery.

Tile colours can vary slightly between batches. If you can't get them all with the same batch number, slight variation can usually be hidden by any of:

  • mixing the batches up randomly
  • changing batch at a corner

Occasionally batches are too different to mix at all. Hold tiles from different batches side by side before buying to check they match near enough.

When transported, tiles sat vertically are a lot less likely to break than if placed horizontally.


Sometimes its possible to surround a window with whole tiles all round. Aligning a ring of tiles round a window is harder than doing a straight line, and typically requires adjusting the tile positions slightly. If doing this, start with this window surround and work out from there.

The cill position can sometimes be moved up or down slightly to match. The new cill tiles can be supoprted on broken tiles cemented in and positioned edge up, spaced around 1/4" apart.

A slight slope to a tile cill reduces water retention and mould.


When you have a replacement tile:

  1. To remove a tile, first scrape out the grout all around it full depth. Then what happens to it won't detach neighbouring tiles.
  2. Smash the tile and knock the pieces off, without knocking neighbouring tiles.
  3. Tidy up the substrate so there's enough room for adhesive and new tile.
  4. Fix new tile & finish in the usual way.

If you don't have a replacement tile, you're limited to sticking the broken pieces back, preferably after gluing the tile back together. Sometimes another option is to insert a picture or feature tile where the broken one was.


UFH makes cold floor tiles comfortable. It requires insulation underneath and a hard substrate on top. Since it raises floor height significantly it can be problematic to retrofit.


Colour is a matter of taste of course, but there are some choices better avoided. The author has seen a house with smallish windows made rather gloomy by laying dark floor tiles. Black tiles show up limescale badly.

Victorian floor tiles

These were done differently to modern tiling.

  1. The tiles are laid on a cement bed, with no gaps
  2. The tiles are soaked before laying
  3. Slightly damp sand/cement mix is brushed back and forth over the tile faces to grout any gaps, then brush it off. Don't press it down at all.


Keep a few spare tiles, otherwise damage is unrepairable, and the tiling sometimes doesn't last as long as a result.

See also

source discussion