How to fit PVC wall panels in a bathroom

Can I fit PVC wall panels over existing tiles?

Yes, if the tiles are stuck fast and the wall is flat. Panels bond straight onto tile with grab adhesive, and stripping tiles off plasterboard usually wrecks the plasterboard.

Tap every tile with the handle of a screwdriver first. Anything that sounds hollow comes off and the hole gets filled flush with filler or bonding. Then clean the glaze. Soap film, shampoo residue and limescale stop adhesive dead, and a solvent PVCu cleaner cuts through all three faster than washing-up liquid. Finally, hold a 2m straightedge on the wall in several places. More than about 5mm out over 2m and you batten rather than bond, because a panel bridging a hollow will telegraph every dip once the light hits it.

Can they go on bare plaster?

Yes, on plaster that is dry, sound and dust-free. New plaster needs weeks to dry properly before anything is stuck to it.

Rub a hand over the wall. If it comes away chalky, seal the surface with a diluted primer and let it dry, or the adhesive will pull the face of the plaster off and take your panel with it. Gloss or silk paint gets sanded to a dull finish. Bare plasterboard is fine. Anything damp is not: find the leak first, because a panel over a damp wall hides the problem and does not stop it.

What adhesive should I use?

An MS polymer grab adhesive or a solvent-free grab adhesive. Solvent-based products can attack the printed face of a PVC panel and craze it.

Run vertical beads at roughly 300mm centres down the back of the panel, plus a bead around the perimeter about 10mm in from the edges. Press the panel to the wall, pull it straight off, wait a minute for the adhesive to skin, then press it back. That touch-and-release step gives an instant grab and saves propping. Allow around one 290ml tube per 2m2 of panel and check as you go, because coverage depends on how heavy your beads are.

If the walls needed battening, use 50 x 25mm battens at 400mm centres, packed level, running at right angles to the panels.

How do the tongue and groove joints go together?

Tongue into groove, tapped home with a timber offcut and a mallet, never the mallet directly onto the panel edge.

Work in one direction across the room so the groove always faces you. Leave 3mm of expansion at the top and bottom of every panel; PVC moves with temperature, and a bathroom swings from cold to steaming twice a day. Stand the panels flat in the room for 24 hours before fitting so they are at room temperature when you cut them. Cut with a fine-tooth saw or a sharp knife scored and snapped, face up.

Which trims do I need, and where?

Starting section at the first edge and around reveals, internal angle in the corners, external angle on any outside corner, quadrant to finish against a bath edge or a tiled return.

Trims go on first, because the panels slot into them. Cut each panel about 3mm shorter than the full depth of the trim channel so it has somewhere to move. Dry-fit the whole wall of trims before any adhesive comes out of the tube; the order of trims around a window reveal is easy to get wrong and impossible to undo once stuck. White trims for white panels, chrome where you want the joint to read as a line rather than disappear.

How do I seal at the bath and in the shower?

Fill the bath with water before you seal it, and leave it full until the silicone has cured. A full bath drops on its feet, and a joint sealed empty tears open the first time someone gets in.

Panels should sit behind the tray or bath upstand wherever the layout allows, so water runs off the panel face and into the tray, not behind it. Use a sanitary anti-mould silicone on the visible joint, tooled to a clean 6mm bead. Do not use silicone to bridge a gap wider than about 6mm; pack it out first or fit a quadrant. Leave 24 hours before the shower is used.

What figures should I work to?

PVC wall panels: working figures

Item	Figure
Acclimatise panels flat in the room	24 hours
Adhesive bead spacing	300mm vertical centres, plus perimeter bead 10mm in
Adhesive coverage	Approx. one 290ml tube per 2m2
Wall flatness to bond direct	Within 5mm over 2m
Battens where walls are out of true	50 x 25mm at 400mm centres
Expansion gap, top and bottom	3mm
Panel cut short into trim channel	3mm
Silicone bead at bath or tray	6mm, sanitary anti-mould grade
Cure before using the shower	24 hours
Wastage allowance	10%

Anything else worth knowing before ordering?

Order a sample pack before you order a room. Panel finishes look different under bathroom lighting than they do on a screen, and the pattern on a marble or tile-effect panel repeats at a fixed interval that you want to see in your hand.

Measure each wall separately, add 10% and round up to whole panels. Awkward rooms, sloping ceilings, boxed-in pipework and shower enclosures with an out-of-square return all change the count. Bring the measurements to the counter or ring us and we will work through it with you.