Tiling onto plasterboard

The plasterboard you’re tiling onto should be dry, securely fixed and rigid with no protruding fixings approx. 200-300mm apart. Ensure the screws have been driven in just enough so they break the surface of the paper, don’t screw too far as this will crush the plaster and prevent a secure fix. The boards should be a minimum 12.5mm thick when fixed to timber framing or battening and fixed in accordance with the manufacturer’s recommendations. Ensure that surfaces to be tiled are flat, clean, sound and free from contamination.

Yes, apply an acrylic based primer such as BAL Primer (undiluted) to the plasterboard with a brush or roller and leave to dry before applying any powered adhesives. All board joints and internal corners should be reinforced using a suitable alkaline joint tape before tiling. It is also advised to apply a thin coat of adhesive onto the tape. If you’re using a ready-mixed adhesive such as BAL White Star Plus then no priming is required.

BAL Primer stabilises dusty surfaces and reduces the porosity of backgrounds, never use PVA to prime a surface before applying tiles; when you treat a surface with PVA it only partly soaks in and sits on the surface of the substrate, much in the same way as wallpaper paste. When you spread tile adhesive onto a wall, the water in the adhesive makes the PVA live again and stops the adhesive from penetrating the substrate and providing a mechanical grip. This means that your tiles, grout and adhesive are all being held in place by a thin layer of PVA, so always use the appropriate primer.

The maximum weight of tiling per m2 on Gypsum Plaster is 20kg/m2 (with plaster skim) or 32kg/m2 on Gypsum Plasterboard direct (without plaster skim). As a general rule, remember to allow approx. 2-4kg/m2 for weight of adhesive and grouts in addition to the weight of tiles. 12mm HardieBacker cement board can take up to 200kg/m2, is water resistant and doesn’t require priming prior to tiling making it an excellent alternative to plasterboard.

BAL Green Star is a simple, but effective ready-mixed tile adhesive for domestic areas including showers, kitchens and bathrooms. It’s perfect for fixing ceramics up to 300mm x 300mm, mosaics and some natural stone in dry or wet interior environments. It is not suitable for porcelain, power showers or wet rooms. Each 15kg tub will cover approx. 6m2 in a dry area, 4.5m2 in a wet area. It cannot be used for floors.

BAL White Star Plus is a non-slip, water resistant ready-mixed adhesive, it’s suitable for showers, kitchens, bathrooms and wet rooms. Use for ceramic tiles no bigger than 300 x 300mm and porcelain 150mm x 150mm. Each 10L tub will cover approx. 6.6m2 in a dry area, 5m2 in a wet area. It cannot be used for floors. For ceramic tiles bigger than 300mm x 300mm and porcelain 150mm x 150mm then a powered adhesive is recommended.

BAL Rapid-Flex Fibre Plus is a non-slip cementitious tile adhesive for walls and floors, formulated with BAL Fibre Strand Technology (FST) for improved flexibility, strength and grab. It’s suitable for dry and wet, interior and exterior areas; including showers, swimming pools and total immersion. Each 20kg bag will cover 10m2 in a dry area, 8m2 in a wet area and approx. 5m2 on a floor.

BAL Flex Fibre Plus has excellent non-slump or and non-slip properties, it has gel rheology meaning it maintains its structure making it ideal for large format tiles and both walls and floors. Formulated with BAL Fibre Strand Technology (FST) for improved flexibility, strength and grab, it’s suitable for dry and wet and interior or exterior areas, including showers, swimming pools and total immersion. Each 20kg bag will cover 10m2 in a dry area, 8m2 in a wet area and approx. 5.3m2 on a floor.

Most adhesives are available in either white or grey. Generally, when using a lighter tile or grout you should use a white adhesive, and vice versa.

For a sustainable and more eco-friendly option, Regenr8 is a great adhesive available in S1 rapid and standard setting bags of 20kg (white and grey).

British Standards recommend that any water sensitive substrate such as plasterboard, when used in a wet area, should be tanked – even if it states it is “waterproof”. Various methods can be used such as a liquid membrane BAL’s Waterproof 1C or a matting system Topps Waterproof Matting, either method should be applied before tiling.