Tiling & Bathrooms Calculators

Tiling is one of the most visible and critical elements of any UK bathroom or kitchen project. Whether you are tiling a small splashback, a full bathroom, or a wet room, getting the quantities right for tiles, adhesive, and grout is essential to avoid mid-job shortages and costly delays. Our tiling calculators provide accurate material estimates with adjustable wastage allowances for different tile layouts and cutting patterns.

UK tile sizes have grown significantly over the past decade, with large format porcelain tiles (600mm × 600mm and larger) becoming increasingly popular for both walls and floors. Common UK tile formats include 300mm × 600mm metro-style tiles, 200mm × 250mm and 250mm × 330mm standard wall tiles, and 600mm × 300mm and 600mm × 600mm floor and wall tiles. Our wall tile calculator handles any tile size and includes grout joint width in the calculation, ensuring your quantity estimate is accurate.

Tile adhesive selection depends on the tile type, substrate, and location. For walls, a standard flexible adhesive (such as BAL White Star Plus, Mapei Kerabond, or Weber Set Flex) is suitable for most applications. Large format tiles and porcelain require a flexible rapid-set adhesive to prevent slippage. For wet areas, the adhesive must be suitable for prolonged water contact. Our tile adhesive calculator estimates the quantity of adhesive based on tile size and the trowel notch size, which determines the bed thickness.

Wet rooms have become increasingly popular in UK bathrooms, particularly for en-suites and accessible bathrooms. A wet room requires a fully tanked (waterproofed) floor and walls using a tanking membrane or liquid tanking system (from brands like Mapei Mapelastic, BAL Tank-it, or AquaSeal). The floor must have a gradient towards the drain, typically 1:80 minimum. Building Regulations require adequate ventilation in all bathrooms, with a minimum extraction rate of 15 litres per second for intermittent fans or 8 litres per second for continuous fans. Our bathroom extraction rate calculator helps you specify the correct fan size for your bathroom.

Grout comes in two main types: cementitious grout (standard, available in a wide range of colours) and epoxy grout (more expensive but fully waterproof and stain-resistant). For most UK bathroom tiling, a flexible cementitious grout with a joint width of 2–3mm is standard. Wider joints (up to 10mm) are used for natural stone and rustic tiles. Always use a grout colour that complements your tiles, and seal cementitious grout in wet areas to improve water resistance.