In the rooms where damp is a fact of life, kitchens, bathrooms and utility rooms, 12.5mm moisture resistant plasterboard is the board to line the walls and ceilings with, and buying it in bulk keeps the material cost down on larger jobs. This is 12.5mm tapered edge wallboard built around a gypsum core treated to resist moisture, giving it more tolerance of humidity and occasional damp than a standard board, which helps hold off swelling, deterioration and surface mould in rooms where the air carries water.

Each board measures 2400mm x 1200mm and covers 2.88m², a full standard sheet that falls on 400mm and 600mm stud and joist centres and closes off large areas quickly. The tapered long edges are made for taping and jointing: the recess lets scrim tape and jointing compound sit flush with the board face, giving a smooth base ready to tile over or to skim and decorate. It fixes with standard tools, screwed to timber or metal stud frames or bonded to masonry, blockwork or brick by dot and dab.

The moisture resistance is built into the core, not just the surface. Additives worked through the gypsum slow the take-up of water, so the board holds its shape and integrity in humid conditions far better than standard wallboard. That is what makes it the right lining behind tiling on a bathroom wall, around a kitchen sink run or across a utility room ceiling, where standard board would be at risk over time.

Moisture resistant is not the same as waterproof. The board is made for humidity and intermittent moisture, not continuous wetting or direct water contact, so in wet rooms, shower enclosures and tanked areas a tile backer or cement board is the correct choice. Install it in line with the manufacturer's guidance and your project specification. Ordering in bulk suits larger bathroom, kitchen and utility fit-outs, multi-plot new build and repeat trade work, where lining a lot of damp-prone area at a lower cost per board tells on the material bill.

Key Benefits of 12.5mm Moisture Resistant Plasterboard:

• 12.5mm moisture resistant gypsum plasterboard for internal walls and ceilings in humid rooms.
• Gypsum core treated to resist moisture, reducing the risk of swelling, water damage and mould growth.
• Suited to kitchens, bathrooms and utility rooms where standard wallboard is not appropriate.
• Tapered long edges for taping and jointing to a flush finish, ready to tile over or to skim and decorate.
• 2400mm x 1200mm full sheet covering 2.88m², sized to suit 400mm and 600mm stud and joist centres.
• Fixes by screw to timber or metal stud frames, or bonds to masonry, blockwork or brick by dot and dab.
• Compatible with standard finishing, jointing and tiling techniques.
• Insulation UK own-brand board bought in bulk, at a lower cost per board on larger orders.

Good to know:

• Moisture resistant, not waterproof. Made for humidity and intermittent damp; for wet rooms, showers or tanked areas that take direct water, use a tile backer or cement board.
• Tapered on the long edges only. Cut ends and board ends butt together, so tape and fill those joints as you would any butt joint.
• A base for tiling. It gives a stable substrate for tiling in a bathroom or kitchen; follow the tile adhesive and weight guidance for the board.
• Store flat and dry. Keep boards flat, off the ground and out of the wet before fixing, and lift in pairs.
• Check the specification. Confirm the board suits the room and build-up against the manufacturer datasheet and your project requirements.

For lining the damp-prone rooms of a job in one go, 12.5mm moisture resistant plasterboard is the board to buy in quantity: a standard-size, taping-and-jointing board that stands up to humidity, takes tile or decoration cleanly and costs less per sheet the more you order.