Can you tile over existing tiles?

Yes, you can usually tile over existing tiles inside a house, as long as the old tiles are firmly stuck, flat and clean. That is the advice in adhesive maker Ardex's technical bulletin on tile-on-tile work, which also lists where it does not suit, like pools and a leaking shower.

Below is when it works, when to strip the old tiles instead, how the surface is prepared, what each option costs, and the Queensland rules for wet areas. These are market prices from cost guides, checked on 12 October 2026. They are not a quote from us.

Can you tile over existing tiles?

Yes, in most rooms inside a house, if the old tiles are in good shape. Ardex's Technical Bulletin TB117 (July 2024) says ceramic tiles can go over existing tiles in internal areas, with the right adhesive system. It sets these conditions:

• The old tiles must be sound, with no loose or drummy (hollow-sounding) tiles. The new layer only holds if the old one does.
• The new adhesive must cover 100% of both the old tile face and the back of each new tile.
• Any movement joints in the old tiling must carry through the new layer. Ardex says leaving them out can cause cracking.
• On walls, the tile weight per square metre must be checked, because the wall now carries two layers.

What's The Damage's Gold Coast tiling page gives a simple first check. Have the tiler tap-test the old tiles. Any that are loose or sound hollow have to come up anyway.

When should you not tile over old tiles?

Strip the old tiles when the base is the problem, or when the area gets a lot of water or movement. Ardex's bulletin rules out, or warns against, these jobs:

• A shower that leaks. New tiles in a shower recess "will not remedy waterproofing problems unless the leak is addressed".
• Swimming pools and ponds. Ardex does not recommend tile-on-tile there.
• Some outdoor areas. High walls, cantilevered verandas or decks (ones that stick out with no posts under the edge), and tiled driveways move too much. Shaded outdoor walls and floors that drain well are fine.
• Heavy or large format tiles on walls. Ardex says these over old tiles "should not be considered a safe installation".
• Large tiles over small ones on a flexible floor. Ardex says this may not work, because the two layers handle movement differently.

Tiles also move a little with heat and moisture, and two layers can move differently. So an outdoor area that gets full sun and rain needs careful thought first. If any of these apply to your job, plan to strip the old tiles.

How do you prepare old tiles for new tiles?

Clean them, rough them up or prime them, then use an adhesive the maker approves for tile-on-tile. Ardex gives three ways to do it.

Construction Chemicals, another Australian adhesive maker, sets out similar steps in its own guide. Scrub the tiles, mop off the residue with clean water, let them dry, then prime (its primer is for dry, internal areas). If the old tiles are sealed or polished, it says to abrade them, and to do a test area if in doubt. It allows about 24 hours before grouting.

Large format tiles need a very flat base. Ardex says they may need a smoothing coat over the old tiles first, rather than going straight on.

Can you tile over tiles in a shower?

It can be done with the right adhesive, but stripping back is the safer path. What's The Damage's Gold Coast tiling page gives the reason: in a shower, the old membrane cannot be checked under the tiles.

That matters because the building code sets firm rules for showers. Under NCC 2022 Part 10.2, the shower floor must be waterproof, including any hob or step-down. The shower walls must be waterproof to at least 1800 mm above the floor substrate (the base under the tiles). A new layer of tiles does not change what is underneath. If the old membrane has failed, it is still failed.

Ardex does list adhesives for tile-on-tile in wet areas, so the method exists. But if you know the shower leaks, new tiles will not fix it. The leak has to be found and fixed first.

For what new waterproofing costs and who can do it, see our guide to bathroom waterproofing cost in Queensland.

Is it cheaper to tile over tiles or remove them?

Tiling over saves the cost of removal, which What's The Damage (Gold Coast page) puts at $20 to $54 per m2. These are the other lines that decide the price.

The prices include GST. What's The Damage adjusts national cost data for each city, so these are not prices from a survey of Gold Coast jobs. The same page puts a standard bathroom's floor and wall tiling, supplied and laid, at $2,750 to $7,350 before waterproofing.

Tiling over still needs its own prep, like cleaning, grinding or priming, and the table does not price that. Ask each tiler to show the prep as its own line, so a tile-over quote and a strip-out quote compare fairly. Our bathroom renovation cost guide shows what the rest of a bathroom costs.

What changes when you tile over old tiles?

The floor gets higher, and the walls carry more weight. What's The Damage notes that a second layer raises the floor at doors and thresholds. Check how the doors and the step into the next room will sit before you commit.

On walls, Ardex says the second layer loads the first layer of tiles and adhesive, and then both layers load the wall behind. Fixing into the wall itself may be needed.

You also keep whatever is under the old tiles. Ardex notes that grinding the surface will usually show up old tiles that are not sound. A strip-out shows you the whole base, and What's The Damage says an uneven one then needs levelling, at $15 to $49 per m2.

Can you tile over a kitchen splashback?

Yes. A splashback is one of the easier places to tile over, because it is a small area of wall. Ardex says small areas of new tiles can be stuck onto cleaned internal wall tiles, such as a splashback, with a flexible adhesive meant to "tidy up" tiled areas.

There are limits. Ardex says that method is not for tiles larger than 200 mm square, stone tiles, or heavy, thick tiles. Bigger or heavier tiles need one of the full methods above.

What's The Damage (Gold Coast page) puts a tiled kitchen splashback, supplied and installed, at $390 to $1,175. In an older home, check what the splashback is made of before anyone cuts into it. The QBCC lists splashbacks among the places asbestos can turn up (more below).

What Queensland rules apply to tiling over tiles?

The building code and licence rules are the same whether you tile over or strip back. This is a short summary, not legal advice.

• The building code. Queensland still uses NCC 2022 for building work. Business Queensland says NCC 2025 will not start here until 1 May 2027. Its Part 10.2 sets the wet area waterproofing rules above.
• Licences. The QBCC says building work over $3,300 must be done by a licensed contractor, and plumbing, drainage and gas fitting need a licence at any value. Waterproofing has its own QBCC licence class, covering work to "apply, install and repair waterproofing, including surface preparation".
• Asbestos. The QBCC says many homes built before 1990 may contain asbestos, and it can be harmful once disturbed. If you are unsure, it says to have the material checked by a licensed asbestos assessor. What's The Damage adds that the wall sheeting behind old tiles can contain it.

A certifier or the official page has the final word for your job.

We do full bathroom renovations on the Gold Coast: strip-out, framing, tiles, vanity and toilet. Waterproofing is done by the right trade, and licensed trades do the plumbing and electrical. Brett books and runs the trades, and you get a timeline with the proposal. See our bathroom renovations page.

Where does this information come from?

Checked on 12 October 2026: Ardex Australia (Technical Bulletin TB117.012, tiling over existing tiles, July 2024), Construction Chemicals (tiling over existing tiles, February 2022) and What's The Damage (tiling cost Gold Coast, October 2026). Rules from the Australian Building Codes Board (NCC 2022 Part 10.2), Business Queensland (NCC 2025 start date, September 2026) and the QBCC (licence pages, and its asbestos notice of November 2023). We will check the prices again every three months.

See our bathroom renovations work, or check what your job will cost.