Tile Backer Board – Insulated Waterproof XPS Tile Backer Boards, 1250x600mm, 4mm-20mm – Walls, Floors & Wet Rooms

What Is Tile Backer Board?

Tile backer board is a rigid, insulated XPS foam panel faced with a fibreglass-reinforced coating on both sides, purpose-built as a stable, waterproof substrate for tiling. Unlike plywood or standard plasterboard, tile backing board won't swell, rot or delaminate when it gets wet, which is why it's become the standard choice for wet rooms, bathrooms, kitchens and shower enclosures across the UK. Each board measures 1250 x 600mm and is available in 4mm, 6mm, 10mm, 12mm and 20mm thicknesses, sold in packs of 5 up to 50 boards, so you can match both the board and the quantity to the job rather than over- or under-specifying.

Key Features & Benefits

Because the core is closed-cell XPS foam, every board carries genuine thermal insulation value alongside its waterproofing properties — useful when tiling over cold solid floors or exterior walls. The reinforced facing gives excellent adhesion for tile adhesive straight from the bag, with no need for a separate primer or membrane in most applications. Boards are lightweight compared with cement particle board, which means faster handling, easier cutting with a straightedge and utility knife, and less strain when tiling overhead on ceilings or shower walls. The waterproof tile backer board construction also resists mould growth, making it a sound long-term choice behind tiled surfaces in permanently damp areas.

Where To Use Tile Backer Board

This insulated tile backer board is suitable for both wall and floor applications. As a wall tile backer board it's ideal in showers, bathroom splashbacks, kitchens and utility rooms, and works equally well as a floor tile backer board beneath ceramic, porcelain or natural stone tiles. It's a natural fit for wet room floor and wall builds where a fully waterproof tiling substrate is essential, and the thinner boards make a good insulated underlay when tiling over underfloor heating systems, cutting heat loss downward while still allowing efficient heat transfer up through the tile.

Choosing The Right Thickness

4mm and 6mm boards suit floor applications and situations where build-up height is limited, such as tiling directly over an existing floor. 10mm and 12mm are the standard specification for walls and shower enclosures, giving extra rigidity and impact resistance behind larger format tiles. 20mm is aimed at floor insulation and levelling duties, or where additional thermal performance is the priority. As a rule of thumb: go thinner for floors where height matters, thicker for walls and heavy tiles.

Pack Sizes & Bulk Pricing

Every thickness is available in packs of 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 boards, with the price per board stepping down as pack size increases — ideal for tilers and trade buyers ordering for a full job rather than a single wall.

Installation Basics

Tile backer board is fixed using a bed of tile adhesive with mechanical fixings (screws and washers) at the recommended centres, then taped and sealed at joints with a waterproofing tape and sealant system before tiling directly onto the board. All joints and internal corners should be properly sealed to maintain a fully waterproof tiling substrate, particularly in shower enclosures and wet rooms.

Delivery & Lead Times

Each board covers 0.75m². Free UK delivery is included as standard, with typical dispatch in 3-5 working days.