Drywall or plaster in a bathroom: which handles moisture better

What actually separates moisture-resistant board from wet plaster

Moisture-resistant plasterboard, sometimes called green board, has a treated core and a water-repellent facing paper. It resists damp air and occasional splashing well, but it is not a tanking layer on its own — it still needs a waterproofing membrane or coating before tile goes on, especially at floor level and around the shower.

Wet plaster, usually a cement-based render, is built up in layers directly on masonry or concrete and can take a proper waterproof slurry or membrane bonded straight to it. It handles constant wetting better and copes with slightly uneven walls, which is common in older buildings, but it takes days to cure between coats rather than the same-day fix of a board.

When moisture-resistant drywall is the right call

Board makes sense when you are building a new partition, boxing in pipework, or need to bring a wall forward to hide services — a stud frame with moisture-resistant board is quick to put up and stays light, which matters on upper floors of a panel building where every kilogram on the structure is worth thinking about.

It also suits a bathroom being renovated on a tighter budget or timeline, since it goes up dry, takes membrane the same day once joints are taped, and can be tiled soon after. Plasterboard work like this is something we quote from 28 € per job, depending on the size of the wall and how much reworking of services is involved.

When wet plaster earns its extra time

Plaster is the better choice on solid masonry or concrete walls that are out of true, which is common in 1930s houses in Kalamaja or Nõmme and in some panel flats where the original render has moved over the decades. Board would need heavy packing to level it; plaster simply builds up thickness where needed.

It is also the more robust base directly behind a shower head or bath overflow, where a wall gets properly soaked rather than just splashed, and where you want a fully bonded waterproof coating rather than taped board joints doing the work.

Waterproofing is what actually keeps the water out

Neither board nor plaster is waterproof by itself. What stops water reaching the structure is a liquid membrane or waterproofing tape system applied over the top, especially in the shower area, along the floor-wall junction, and around every pipe penetration. This is the layer that fails first if it is skipped or rushed, whichever board is underneath.

A membrane needs the right primer, full coverage with no pinholes, and enough drying time before tiling starts — cutting that short is the single most common cause of a bathroom that looks fine for a year and then leaks into the flat below.

What we choose in a typical Tallinn panel flat bathroom

Most panel flat bathrooms have concrete walls that are reasonably flat and a small footprint, so we default to moisture-resistant board on any new partition or service wall, and plaster only where the original concrete needs correcting or where a wall takes direct water. Waterproofing membrane goes over both before tiling, without exception.

This mixed approach is usually the fastest route to a bathroom that holds up, and it is what we build into a full bathroom renovation, priced from 3500 € per job depending on layout, plumbing changes and finish. Tiling itself, once the substrate and membrane are ready, starts from 35 € per job.

Check these things before you decide

A short list is easier to work through than trying to hold the whole decision in your head, especially when a tiler or supplier is waiting for an answer.

Walk the room with these points in mind before committing to board, plaster, or a mix of the two.

• How flat are the existing walls — check with a straight edge before assuming board will go up easily
• Where does the wall get direct water versus just damp air
• Is the wall load-bearing or being newly built as a partition
• Has a waterproofing membrane been budgeted for as a separate step, not assumed included
• How much drying time does the plan allow before tiling has to start
• Are pipes being moved, which affects whether boxing in with board is simpler than replastering