Cut condensation in a bathroom — HomeGraft

Reduce bathroom condensation and mould by fixing airflow, cleaning the fan, and resealing damp-prone edges.

BC-01Test your extractor fan is actually workingTurn on the fan and hold a piece of tissue near the grille. If it flutters and holds against the grille, the fan is pulling air out properly. If it barely moves, the fan may be blocked, weak, or wired to run for too short a time. Note what you find before moving on, since a weak fan is often the main cause of condensation.

RULES

1 sheet · Tissue paper

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KNOW THE RULES

New extractor fan installation or rewiring in a bathroom is notifiable electrical work under Part P of the Building Regulations. If the fan needs replacing or rewiring, use a Part P registered electrician or get the work checked by Building Control - don't rewire it yourself.

BC-02Clean the extractor fan grille and outside ventSwitch the fan off at the isolator or consumer unit before you touch it, even just to clean it. Unclip or unscrew the front grille and wipe away dust, mould, and cobwebs with a damp cloth. Check the outside wall vent too - a vent clogged with debris or a bird's nest stops the fan working properly.

1 each · Soft cloth

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1 each · Small flathead screwdriver

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BC-03Extend the fan's run-on time if it has a timer or humidistatMany bathroom fans have a small dial behind the grille that sets how long the fan runs after you leave, or how much moisture triggers it. Turn the dial up so the fan runs for 15-20 minutes after a shower, not just while the light is on. Only touch the dial itself - never the wiring behind it.

1 each · Small flathead screwdriver

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BC-04Improve airflow during and after showersOpen trickle vents on windows and keep the bathroom door open once you've finished, so the fan draws in fresh air instead of recirculating the same damp air. Run the shower with the door shut and the fan on, then leave the fan running with the door open afterwards. This single habit cuts condensation more than almost anything else.

BC-05Squeegee wet surfaces after every showerWipe down tiles, glass screens, and the bath or shower tray with a squeegee straight after use. It takes 30 seconds and removes most of the moisture that would otherwise sit and feed mould. Hang the squeegee up dry rather than leaving it wet on the tray.

1 each · Shower squeegee

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BC-06Treat existing mould spotsSpray a dedicated mould remover onto black spots on tiles, grout, and sealant, and leave it for the time stated on the bottle - usually 10-15 minutes. Wipe off with a damp cloth and rinse. Wear gloves and open a window, as these sprays contain bleach and the fumes are strong.

1 bottle · Mould remover spray

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1 pair · Disposable gloves

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1 each · Cloth

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BC-07Cut out and replace failed silicone sealantIf mould has worked its way inside the silicone around the bath or shower tray, cleaning the surface won't fix it - the sealant needs replacing. Slice along both edges of the old bead with a sealant removal tool or sharp blade, keeping fingers behind the blade, then peel it out and clean the gap with methylated spirit. Run a new bead of mould-resistant silicone with a caulking gun and smooth it with a wet finger or sealant tool.

1 each · Sealant removal tool

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1 tube · Mould-resistant silicone sealant

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1 each · Caulking gun

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1 bottle · Methylated spirit

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1 pair · Disposable gloves

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1 roll · Masking tape

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BC-08Lag any cold water pipe you can see under the bath panelUnclip or unscrew the bath panel to check for exposed pipework - a cold pipe in a warm, damp room attracts condensation just like a cold drink glass. Slide foam pipe lagging over any bare cold pipe and tape the ends. Refit the panel once you're done.

1 length · Foam pipe lagging (1m)

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1 each · Screwdriver

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BC-09Add a moisture absorber for a windowless bathroomIf your bathroom has no window and still feels damp after these changes, place a moisture-absorbing tub in a corner away from the bath or shower spray. Replace the crystals or empty tub once it fills with collected water, usually every few weeks. Treat this as a cheap backup, not a substitute for a working extractor fan.

1 each · Moisture absorber tub

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BC-10Tidy up and let everything settleRinse cloths and the squeegee and hang them to dry. Wipe down any surfaces you sprayed with mould remover once rinsed. Leave the bathroom door open and the extractor running for an hour, and avoid using the bath or shower for 24 hours so new sealant can cure properly.

1 each · Bin bag

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