Moisture-resistant plasterboard is specifically designed to tolerate moist and humid conditions such as those found in a bathroom or kitchen. Moisture-resistant plasterboard is not waterproof as such but is resistant to atmospheric dampness like you would find in a bathroom. MR plasterboard consists of an aerated gypsum core, with its water resistance coming from the water-repellent additives encased in the core and paper liners. The treatment used to give the plasterboard these properties is green and therefore people will often refer to MR plasterboard as green plasterboard.
Designed for direct tiling application (with no surface preparation required), these drywall green boards should be used in conjunction with other drywall components to create partition and ceiling systems that resist moisture.
Generally used in high moisture and humid environments, moisture board has a host of other uses and benefits:
MR plasterboard should be used in situations where there is increased humidity. This would apply to both high moisture areas like bathrooms and kitchens.
At Materials Market we sell Gyproc moisture-resistant boards (12.5mm and 15mm), Knauf moisture-resistant tapered edge (12.5mm and 15mm), and Siniat moisture-resistant tapered edge (12.5mm and 15mm). We don't sell square edge moisture-resistant boards.
It is always best to look at the root cause of the problem with the damp before doing anything else to it. Affixing any kind of board to a high moisture damp wall may just be storing up problems for the future. If you do decide to take this step, however, the best way is to put batons between the wall and the boards, that way the moisture is not transferred directly into the boards. It is still possible for damp walls to transfer moisture to moisture plasterboard over a longer period of exposure otherwise.
Skimming refers to the process of plastering smoothly over a surface, for example, to disguise the fact there are multiple panels of green drywall and present it as a uniform surface for further decoration if desired.
It is indeed possible to skim moisture-resistant plasterboard and it is recommended that a bonding agent is used before starting the skimming process, though some people in the building industry believe that it is possible and easier just to skim directly onto the moisture-resistant plasterboard, so it is a matter of personal choice how you accomplish the task.
It is possible to apply paint directly to the surface of MR plasterboard and the water repellent liners but it must first be prepared with a plaster bonding agent in order for the paint to adhere to the surface. This is in accordance with the British Gypsum guidelines.
Yes, if you are using it for the purposes for which it is intended, MR plasterboard offers many benefits. It really comes into its own when used for semi-exposed areas like kitchen and bathroom projects where ordinary plasterboard would not be able to cope with the damp conditions and this alone makes it worth the extra cost vs standard plasterboard sheets.
On the whole, most moisture-resistant boards feature a low thermal conductivity, however, we don't recommend them as a heat-retaining insulant.
One benefit of plasterboard is that it's 100% recyclable and is considered to be an environmentally friendly material as no waste should be required to go to landfills.
Moisture-resistant plasterboard is not fireproof but there are different types of treatments that can be done to plasterboard to give it more fire resistance; you can find our own selection of fire resistant plasterboard here. While these are not fireproof per se, they add significantly to the amount of time that it will take for a fire to spread and therefore increase the safety of any home or building they are installed in.