DAMP, MOULD & CONDENSATION

Line a cold wall with thermal lining paper

Prepare your wall, then paste and hang thermal lining paper to cut condensation and warm up a cold wall.

TL-01Check what's actually causing the cold, damp feelThermal lining paper helps with general condensation and cold spots, not with damp coming through the wall. Look for a musty smell, black speckled mould, or patches that stay wet in one spot only — that points to penetrating or rising damp, and needs sorting first, not papering over. If the whole wall just feels cold and gets misty or mouldy in cold weather, that's condensation, and lining paper will help.
TL-02Clear the room and protect your floorMove furniture away from the wall and take down pictures, curtains and shelves. Lay dust sheets along the skirting and open a window — stripping and pasting gets messy and damp. Give the wall a wipe with sugar soap to remove dust and grease.
2 each · Dust sheet
1 bottle · Sugar soap
TL-03Turn off the power before touching any socket or switchIf a socket or light switch sits on the wall you're papering, switch off that circuit at the consumer unit before loosening its faceplate — you'll need to paper right up to and slightly behind it. Never paper over a faceplate while it's live. This is just switching off for safety, not altering the wiring, so it's not notifiable electrical work.
1 each · Screwdriver
TL-04Strip old wallpaper and loose paintScore old wallpaper lightly and soak with warm water and stripping solution, then scrape off with a wallpaper scraper. On solid brick or block, scrape firmly — the wall can take it. On lath and plaster, go gently: old plaster is soft and can crumble or come away from the laths behind. On plasterboard, whether it's on timber studs, metal studs, or dot-and-dab, don't over-soak the paper — too much water can soften the board's paper facing.
1 bottle · Wallpaper stripper solution
1 each · Wallpaper scraper
TL-05Treat any mould before you cover it upWipe visible mould with a fungicidal mould wash or a mild bleach solution, wearing gloves and keeping the window open. Leave it to dry fully for at least a few hours — sealing damp mould behind lining paper just traps the problem.
1 bottle · Fungicidal mould treatment spray
1 pack · Disposable gloves
TL-06Fill and sand cracks or holesOn solid brick or block and on plasterboard (timber studs, metal studs or dot-and-dab), fill cracks and holes with multi-purpose filler and sand flush once dry. On lath and plaster, use a flexible filler and lay scrim tape over any wider cracks first — old plaster moves slightly, and rigid filler will crack out again.
1 tub · Multi-purpose filler
1 roll · Scrim tape
1 each · Filling knife
1 pack · Sandpaper
TL-07Size the wall so the paste behavesBrush on a coat of size — wallpaper paste mixed thinner than usual — and let it dry for about an hour. This matters most on solid brick or block and bare plaster, which are porous and will suck the paste dry before you can position the paper. Plasterboard walls (timber stud, metal stud, or dot-and-dab) are less thirsty, so one light coat is enough.
1 pack · Wallpaper paste
1 each · Pasting brush
TL-08Measure and cut your lengthsThermal lining paper is usually hung horizontally, so any top layer of decorative wallpaper you add later has its joints in a different place. Measure the wall's width for each drop and add 100mm for trimming at each end, then cut your lengths on a flat table and number them in the order you'll hang them.
1 roll · Thermal lining paper (10m roll)
1 each · Tape measure
1 each · Sharp trimming knife
TL-09Paste and hang the first lengthApply paste evenly across the back of the paper, working from the centre out. Fold the pasted ends together (booking) and leave for a few minutes so the paste soaks in evenly. Starting at the top corner of the wall, hang the length and smooth it out with a hanging brush, working from the middle outwards to push out air bubbles.
1 tub · Ready-mixed heavy-duty wallpaper paste
1 each · Hanging brush
TL-10Hang the rest of the lengths, butted not overlappedButt each new length against the edge of the last one — never overlap, as it shows through once painted. On solid brick, block or dot-and-dab walls, run your hand over the surface once hung and feel for high spots or lumps behind, which are easier to catch now. Stud walls (timber or metal) tend to give a flatter surface, so joints sit more easily. Keep joints clear of socket and switch edges where possible.
1 each · Seam roller
TL-11Trim around skirting, ceiling and socketsPress the paper into the angle at the skirting and ceiling with the bristles of your hanging brush, then trim along the crease with a sharp knife and a straight edge for a clean line. Trim carefully around switch and socket plates, keeping the power off at the consumer unit while you work close to them.
1 each · Metal straight edge
TL-12Let it dry properly before doing anything elseLeave the paper to dry for 24–48 hours with the room gently ventilated — a cracked window is fine, but avoid blasting it with a heater, which can dry the surface too fast and cause it to lift. Don't paint or paper over the top until it's fully dry, or you'll trap moisture underneath.
TL-13Tidy up and put everything backOnce the paper is dry, screw the socket and switch faceplates back on and turn the circuit back on at the consumer unit. Wipe down your tools, bin the offcuts, and only move furniture back against the wall once you're sure it's fully dry.

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