Stripping a bathroom back to the walls
A bathroom renovation looks like a list of new things: a shower, a basin, tiles, perhaps a heated rail. What decides whether it lasts is what you find once the old finishes are off, and that is worth planning for before a single tile is chosen.
Take the old tiles off with care
Start at a corner or beside a fitting where a tile edge is exposed, and work along with a bolster and club hammer held low. The aim is to see what the tiles were stuck to, so avoid smashing straight through into the backing. On plasterboard the paper face usually comes away with the adhesive, while solid plaster may release the tiles cleanly or come off in chunks with them.
Read the wall you uncover
The back of the old tiles, and the surface behind them, show how the room has behaved for years. Pale, dry adhesive and firm plaster mean the tiling kept water out. Dark staining along the joints, plasterboard that crumbles under a thumb, or black growth on the back of the tiles mean water has been getting through, usually at the edge of the shower tray, around a tap, or along the bottom row.
Mould that has spread across the face of the board behind the tiles is not a grout problem, and it will not stay put behind new tiling. On a stud wall, test the timbers and the floor beneath with a screwdriver: soft timber is cut out, never sealed in. Where the growth covers more than a small patch, or a musty smell rises from under the floor, the wall needs professional attention before it is boarded again. Renovators in North Carolina often arrange bathroom mold removal in Charlotte before any new board goes up, and the logic holds wherever you live: tiling over contaminated board only hides the trouble for a few more years.
Rebuild with the right board
In the wet zones, replace plasterboard with cement-based or foam tile backer board, screwed at the spacing the manufacturer specifies. Moisture-resistant plasterboard is fine elsewhere in the room but it is not waterproof, so it has no place inside a shower enclosure. Joints and screw heads in the wet area are taped and tanked before any adhesive goes on.
Plan for the air as well as the water
A renovation is the cheapest moment to sort out ventilation. With the ceiling open, a fan can be ducted by the shortest route to the outside, with the duct falling slightly away from the fan so that condensation drains outwards rather than back. Choose a fan sized for the room, wired to keep running after the light goes off, and leave a gap under the door so replacement air can get in.
Keep a record
Photograph the walls before they are closed and note what you found and what you changed. The next person to open that wall, possibly you in fifteen years, will want to know whether it was sound and dry when the new tiles went on.