A damp laundry day can quietly turn a cosy home into a clammy one — fogged windows, a musty edge on the stairs, that tell-tale black halo above a skirting board. Venting your tumble dryer outside sounds old-school, almost boring. Yet it might be the small, practical move that makes the mould ease off and your bills breathe out.
Inside my own flat, the windows were beading after a weekend of drying clothes on racks, the air heavy, the bathroom fan losing the fight. The mould at the back of the wardrobe? Back again.
We’ve all had that moment when you move a sofa and your heart sinks. You don’t want another gadget, another routine, another lecture about perfect housekeeping. What you want is air that doesn’t feel sticky and walls that stay clean.
A short duct through an outside wall can be enough. It’s small, cheap, and unglamorous. And it changes the room.
Warm, wet air is sneaky — and it’s costing you
Every cycle, a typical 7 kg tumble dryer evaporates roughly two to three litres of water from your clothes. If that moisture lingers indoors — from a condenser unit that leaks warmth back into the room, or a portable vent kit that blows into a bucket — it doesn’t just fog the glass. It raises humidity, pushes damp into cold corners, and feeds spores that love still air.
I visited a couple in Leeds who never thought about their dryer. They used a flexi hose perched on the window ledge, which slipped on windy days and puffed into the kitchen. Mould crept behind the kickboards, a sweet, unpleasant whiff when you opened a drawer. They fitted a proper through-wall vent with a flap and a short rigid duct — under £40 — and within a week the glass stopped weeping and that smell eased. Their winter gas bill? Slightly lower, because they weren’t heating a home that felt perpetually clammy.
Here’s the quiet physics: drier air is easier to heat and less likely to condense on cold surfaces. When you push warm, moist exhaust outdoors, you’re not asking your home to swallow it. That means fewer patches on paint, fewer hidden damp traps, and fewer hours with the boiler nudged up. A tight vent run also helps the dryer finish faster, which trims electricity use. It’s not magic. It’s friction, moisture, and pathways.
The simple how-to: venting to the outside, neatly
Start with the route. The best path is the shortest, straightest line from the dryer to an external wall. Measure from the outlet to the brickwork, then buy a rigid duct and an external grille with a backdraft flap to match the diameter (usually 100–102 mm). Rigid or semi-rigid duct beats thin foil hose because it reduces lint traps and back-pressure. Keep the run under two metres if you can.
Drill a core hole or use an existing vent if you’re lucky. Fit the sleeve, then the outside grille. Indoors, connect the duct with a smooth elbow, secure with a proper clamp, and run a thin bead of silicone where the sleeve meets the wall. Add a gentle downward fall to shed any stray condensation. Let the flap swing freely outdoors with no ivy, no cobweb build-up, no cluttered bins blocking airflow.
Let’s be honest: nobody measures duct runs with a tape before buying a vent kit. Still, a few calm checks save headaches. Don’t crush the hose behind the dryer — leave a hands-width gap. Clean the lint filter every cycle and the duct every few months with a brush kit. If you’re renting, a removable window vent panel might be your friend until the landlord green-lights a permanent hole.
“We used to think the mould was ‘just old house stuff’,” says Aaron, who lives in a 1930s semi in Nottingham. “Once the dryer vent was sorted, the bathroom actually stayed mirror-clear after showers. The whole place felt lighter.”
- Rigid duct and a louvred flap cut lint build-up and noise.
- Short, straight runs help the motor breathe and dry faster.
- Seal the wall sleeve edges to stop sneaky draughts.
- Keep the external flap clear so it doesn’t stick open.
What about energy, noise, and the “is it worth it” question?
There’s a common worry: won’t a vented dryer pull in cold air and nudge up heating use? In a leaky house, any fan shifts air. Yet the trade-off changes when you stop bathing your rooms in steam. Drier air carries less hidden heat and feels warmer at the same thermostat setting. Your dryer also runs more efficiently when it isn’t pushing through a kinked or long, squishy hose.
*Yes, a small hole in a wall can change how your home feels.* That’s because you’re guiding moisture along a path of least resistance. Less damp means fewer black freckles on the ceiling, fewer bleach-fuelled clean-ups, and fewer late-night worries about that patch behind the wardrobe. And if you’ve been drying clothes on radiators, sending moisture outside is a clean break from the cycle.
Heat-pump dryers remain champions for kWh per cycle. If you already own one and love it, keep going. If your reality is a solid, older vented dryer, a tidy outdoor vent with a tight flap and a short run can mean **lower bills**, **less mould**, and a bit of **quiet efficiency**. It’s about making your existing kit work like it should, not buying your way to a fresh start.
There’s a bigger human story in all of this. We live in homes that carry our lives — the laundry basket that never seems to empty, the towels that never quite dry in winter, the window you wipe with your sleeve as you head out. When the air is right, small domestic moments feel easier. When it’s wrong, they rub.
Venting a dryer outside is not a home-renovation epic. It’s a Saturday job with a drill, a hole saw, and a podcast in your ears. You cut a circle, you pop in a sleeve, you clip a duct, you step back. The flap ticks in the wind and then goes quiet.
And yet the ripple effect can be real. Clothes dry properly. The boiler cycles a touch less. The bathroom mirror clears faster. That corner behind the bookcase… stays boringly clean. Share the trick with a neighbour who keeps their window open in January “for the dryer” — they might thank you. Or lend your brush kit to someone down the hall who hasn’t looked behind their machine in years.
| Point clé | Détail | Intérêt pour le lecteur |
|---|---|---|
| Short, rigid duct | Straight run under 2 m, smooth elbows | Faster drying, lower energy, less lint |
| Backdraft flap outside | Louvred grille that shuts when off | Stops draughts and pests, tidy look |
| Routine cleaning | Filter every load, duct brush each season | Safer machine, steady performance |
FAQ :
- Can I vent a tumble dryer outside in a rented flat?Often yes with permission, but a removable window panel is a neat stopgap. It slots where the pane opens and comes out when you move.
- Do I need a professional to core the wall?Many DIYers do it with a 4-inch core drill and care. If you meet brick, cables, or no clue about what’s inside the wall, hire a pro for an hour.
- Will a vented dryer cost more to run than a heat-pump dryer?Usually yes per cycle, but a well-vented machine runs shorter than a choked one, and sending moisture out reduces indoor damp trouble.
- Can I vent into a loft, garage, or crawlspace instead?No — that simply moves the moisture and the mould risk. Always terminate outdoors with a proper grille.
- How often should I clean the duct?Filter every load, quick visual monthly, brush-out each season or after 20–30 cycles. Lint is sneaky and flammable. Keep it boring.
