DAMP, MOULD & CONDENSATION

Dry out a room after a leak

Stop the leak, drain trapped water safely, then dry the room fully before repairing skirting or plasterboard.

DR-01Stop the leak at its sourceFind your stopcock, usually under the kitchen sink, and check it turns before you need it. Turn it off if the leak is from a pipe or tap you can't isolate at source. If it's from an appliance, switch it off at the wall and shut its own valve too.
DR-02Isolate electrics if water has reached themIf water has reached sockets, switches, light fittings or the consumer unit, turn the whole house off at the consumer unit until it's checked. Don't touch any switch with wet hands, and don't turn anything back on until you're sure it's dry and safe.
RULES
KNOW THE RULES

Repairing or replacing wiring or electrical accessories damaged by water is notifiable work under Part P of the Building Regulations and must be done or checked by a registered electrician.

DR-03Record the damage before you startPhotograph every affected wall, ceiling and floor before you move or remove anything. Note the date, time and likely cause. Call your insurer early if the damage looks significant - many have a claims line that will talk you through this stage.
DR-04Clear the room and remove standing waterMove furniture and rugs out of the room, or up onto blocks if underneath is dry. Soak up standing water with old towels, a mop and bucket, or a wet-and-dry vacuum if you have one. Wring out and repeat until the floor feels just damp, not wet.
1 each · Wet-and-dry vacuum (hire or buy)
4 each · Old towels
DR-05Check the ceiling for trapped water and drain it safelyA bulging, sagging ceiling is holding water and can collapse without warning - drain it before it drains itself on you. Work out what's above with a stud detector or a magnet tracing a line of screw heads, and a small pilot hole to check: fine dust means timber joists, grey swarf means a metal frame. Cables and pipes can run almost anywhere in a ceiling and a detector can still miss them, so check your stopcock works before you drill, and isolate the electrics at the consumer unit if you're at all unsure. Find the lowest point of the bulge, well clear of any light fitting, and pierce it with a bradawl or screwdriver tip while someone holds a bucket underneath.
1 each · Stud detector
1 each · Bradawl or screwdriver
1 each · Bucket
DR-06Lift wet carpet and underlayPeel back wet carpet from its grippers and roll it away from the wall to let air underneath. Cut away sodden underlay with a utility knife - it holds water and almost never dries out enough to reuse. Stand the carpet on its edge somewhere ventilated if you're hoping to save it.
1 each · Utility knife
DR-07Remove wet skirting boardsHow you remove skirting depends what's behind it. On solid brick or block, it's usually screwed or nailed into plugs - ease it off with a bolster chisel along its length. On plasterboard over timber studs, it's fixed into the studs at intervals - lever gently near each fixing to avoid snapping the board. On plasterboard over metal studs, it's usually screwed into the metal track at the base - undo the screws where you can reach, or lever carefully if not. On dot-and-dab walls, check behind the skirting for water sitting in the void between the board and the masonry - it's easy to miss and slow to dry, so drill a few 6mm weep holes at skirting height to let it drain. On lath and plaster, work slowly, as wet plaster is already soft and can crumble away from the laths as you lever.
1 each · Bolster chisel
1 each · Claw hammer
1 each · 6mm masonry drill bit
DR-08Cut away badly sodden plasterboardOnly cut away board that's gone soft, swollen or crumbly - firm, damp board will dry out on its own. Work out what's behind it: a stud detector or magnet tracing screw heads, the hollow sound between fixings either way, and a small pilot hole - timber dust means wood studs, grey swarf means metal ones. Before you drill or cut, remember cables and pipes can run almost anywhere behind a wall; check your stopcock works, and isolate the circuit at the consumer unit if there's any doubt at all. Cut along the centre line of the studs either side of the damage with a padsaw, so there's something solid to fix new board to later.
1 each · Padsaw
1 each · Stud detector
DR-09Set up a dehumidifier and air movementPlace a dehumidifier in the centre of the room, away from walls, and close the door to keep damp air from spreading round the house. Point a fan or two at the wettest walls and floor to speed up evaporation. Open a window briefly each day to vent moist air outside if the weather's dry, then close it again so the dehumidifier isn't fighting outside humidity. Run it continuously for several days, emptying the tank at least twice a day at first.
1 each · Dehumidifier (hire or buy)
2 each · Electric fan
DR-10Monitor moisture levels dailyCheck progress each day with a damp meter on the wall, floor and any skirting you've kept - press the pins in and note the reading. Compare it to an unaffected wall elsewhere in the house so you know what normal looks like for your home. Keep drying until readings are close to that normal level and stay there for a couple of days - rushing this is the biggest cause of mould and failed repairs later.
1 each · Damp meter
DR-11Treat any mould that appearsWipe mould with a mould and mildew treatment or a diluted bleach solution, wearing rubber gloves and keeping the room ventilated. Don't paint or redecorate over mould - treat it and let the surface fully dry first. Small patches after a leak are normal; anything widespread or coming back repeatedly means the area isn't dry yet.
1 each · Mould and mildew treatment spray
1 pair · Rubber gloves
DR-12Dispose of wet waste safelyBag up wet carpet, underlay and any plasterboard offcuts and take them to your local household waste and recycling centre - most councils won't take large wet items in a kerbside collection. If the leak involved dirty or waste water rather than clean water, tell the site staff, as some sites handle contaminated waste differently. Check your council's website for accepted items and any booking system before you go.
4 each · Heavy-duty rubble sacks
DR-13Tidy up and plan repairsRinse and dry your tools, wring out mop heads, and empty and clean the dehumidifier tank and filter. Leave the room fully dry before replacing skirting or new plasterboard - fixing new material to a still-damp wall traps moisture behind it and brings mould straight back. Treat skirting and plasterboard repairs as a separate job once your damp meter readings hold steady.

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