Tile size and layout, at least in general
It sets the joint lines, the cuts and where the waste sits. You can pick the exact colour later.
Ask: Do you know the tile size, so the floor and the waste can be set out? Choose it here
Plan · Stage 4 of 10 · 6 decisions
Decide before set-out and screed
Before the floor is screeded and the room is set out. Tile size, bedding depth and falls. Every height in the room is measured from the finished floor this sets.
Copies the decisions shown, with a prompt, to paste into ChatGPT, Claude or Gemini.
Bedding and screed depth
Allow about 40 to 50 mm. It moves the finished floor, and every height in the room is measured from the finished floor.
Ask: Have you allowed 40 to 50 mm for bedding? Your heights are from the finished floor, not the slab.
Wall build-up: sheet, membrane and tile
About 15 to 25 mm is added to the wall face, which moves outlets, niches and set-outs. source
Ask: Have pipe and outlet depths allowed for the finished wall face?
Falls to the waste, and the entry into the shower
Wet-area falls are set by the NCC and AS 3740. Get them wrong and water sits or escapes. source
Ask: Have your tiler and waterproofer agreed the falls and the shower entry?
A finished floor level datum line, marked on the studs
Every fixture height is from the finished floor. Mark it once, then set out from it.
Ask: Is there a datum line on the studs before anything is set out?
Thresholds and floor transitions between rooms
Tile next to timber or carpet needs matching heights and a trim.
Ask: Do the finished floor levels line up at every doorway?
Prompts, not rules. Most choices can wait; these can't, because a later trade builds to them. Code items cite their source; states adopt parts of the NCC differently, so check yours. Your builder, trades, certifier and each product's install sheet decide. Download the list (JSON, CC BY 4.0).