Large-format porcelain is popular in receptions, showrooms, retail and hotels. It gives a clean, modern finish, but it's far less forgiving than standard tiles.
Flatness is everything
A small dip in the floor that a 300mm tile would bridge will show as lipping between two large tiles. The base usually needs to be flatter than for standard tiling, which often means a self-levelling compound first.
Adhesive coverage
Large tiles need a solid bed of adhesive with no voids underneath. They are usually back-buttered as well as bedded into a notched layer of adhesive, so they're fully supported.
Levelling systems and offset
Tile levelling clips help hold neighbouring tiles flush while the adhesive sets. Long rectangular tiles can have a slight bow, so limiting the offset (often to a third of the tile length or less) helps avoid lipping.
Handling
Big slabs are heavy and can crack if handled badly. Lifting frames and suction cups make them safer to move and place.
This guide is general information. Always follow the tile, adhesive and product manufacturers' instructions for your specific project.