Laying your own floor tile: where to start, and when to call someone in

Start in the middle, not at the wall

The instinct is to push the first tile into a corner and work out from there. It is the most common way a floor goes wrong.

Rooms are rarely square. Walls bow, corners are out, and a floor set out from one wall will drift, so by the time you reach the far side you are left with a tapered sliver of tile along the most visible edge. Set out from the centre instead. Find the middle of the room, snap two chalk lines at right angles, and work outward from that cross. The cuts then land at the edges, evenly, where skirting and furniture soften them.

Before any of that, spend your first hour on the floor itself rather than the tile.

The order of work

Almost every problem we get called to fix comes from skipping a step near the start. The sequence matters more than the speed:

• Check the substrate. It needs to be sound, dry, clean and flat. Run a long straight edge across it and look for gaps underneath.
• Level what is not flat. Tile does not bend. A hollow under a tile becomes a cracked tile the first time something heavy lands on it.
• Waterproof, if it is a wet area. This is the step with real consequences, and we come back to it below.
• Set out and dry lay. Lay a full run out with spacers, no adhesive, and see where the cuts fall. Move the centre line if the cuts look mean.
• Then adhesive, then cutting, then grout. Not before.

Dry laying feels like a waste of an afternoon right up until it saves you from a row of ten millimetre cuts down the side of the room.

Get the boring things right

Adhesive and notch size do more for the finished floor than the tile does. Too small a notch and the tile sits on ridges with voids underneath. Too much and it squeezes into the joints and you spend the evening digging it out.

Large format tile is less forgiving than small format, because any dip in the floor shows up as a rocking tile or a lipped edge between two pieces. If you are laying anything six hundred millimetres or bigger, the flatness of the substrate stops being a detail and becomes the whole job.

The same goes for the consumables. Our Trade Line grout, adhesive, sealants and primers are not interchangeable, and the right one depends on the tile, the substrate and whether the room gets wet. It is worth asking before you buy rather than after.

Where these jobs usually go wrong

In our experience the floors that come back for repair share a short list of causes:

• An uneven substrate that was tiled over rather than levelled
• Setting out from a wall, leaving thin tapered cuts on the opposite side
• The wrong adhesive, or the right adhesive with the wrong trowel
• Waterproofing treated as optional in a shower or bathroom
• Grouting before the adhesive has properly cured

None of those show up on day one. They show up months later, as a cracked tile, a loose one that sounds hollow underfoot, or a damp patch on the wall of the next room.

When to call someone in

Plenty of floors are well within reach of a careful DIY job. A laundry, a small entry, a straightforward run of floor tile on a sound substrate: take your time and you will get a good result.

There are four situations where we would tell you to get a tiler in, and we would say the same if you were standing at our counter:

• Wet areas. Showers and bathrooms have to be waterproofed to the standard that applies in New Zealand, and a failure here is not a tiling problem, it is a building problem. The repair means pulling out the floor and often the wall behind it.
• Underfloor heating. The heating goes in as part of the floor build up, so it has to be planned with the tile, not after it. We supply and fit it as one job.
• Large format tile. Anything big enough that flatness becomes critical, especially over a timber floor.
• A substrate you are unsure about. If you are not certain what is under the old floor, or how sound it is, that is the moment to ask rather than cover it up.

Either way, come and talk it through

If you are doing it yourself, bring the room measurements in and we will work out quantities with you, and make sure you leave with the right adhesive, grout and waterproofing for that particular job rather than a guess.

If it turns out to be more than you want to take on, we have our own crew who handle tiling, waterproofing, floor preparation and underfloor heating across Wanaka and Central Otago. Same team either way, which means the advice at the counter and the work on site answer to the same people.

Specifying a floor for a client rather than laying your own? Our trade and specification page covers samples, technical backup and delivery to site.

Common questions