AB-03Check the surface you're dealing withThe method changes depending on what's under the mould. On painted plaster or plasterboard, you can clean and treat directly. On wallpaper, mould often grows behind the paper too — badly affected paper needs stripping, not just wiping. On bare brick or blockwork (garages, cellars, behind furniture), expect to scrub harder over a bigger area. On bathroom sealant around a bath or shower, cut out and replace the silicone rather than cleaning it — mould in silicone rarely lifts fully.