James Whitaker
What You're Actually Dealing With
Dust from a renovation isn't one substance — it's several, and they behave differently. Plaster and filler dust is fine, alkaline and sticky, and it settles on everything, then gets dragged through the house on socks and shoes. Brick, tile and concrete dust contains crystalline silica, which is genuinely harmful to breathe and travels further than you'd expect. Timber dust from sanding is lighter still, and old paint dust from pre-1970s homes deserves caution until you know what you're dealing with.
The single most useful thing to understand is air pressure. Dust follows air movement, so if the rest of your house is at a higher pressure than the work zone, air — and dust — pushes out into your living space. Get the pressure the other way round and dust stays where it belongs.
Seal the Work Zone Before You Start Demolition
Do this on day one, before the first hammer swings. Retrofitting containment halfway through a job is far harder work than setting it up properly at the start.
- Use 1000-gauge polythene sheeting (sometimes sold as 250 micron) rather than the flimsy decorating stuff. It stands up to being brushed past and doesn't tear on a stray nail.
- Fix it with telescopic dust barrier poles and a decent tape — low-tack on painted surfaces, gaffer on anything else. Wipe the surface first; tape won't stick to dust.
- In doorways, fit a zippered dust door rather than taping plastic shut. You'll be going in and out fifty times a day, and a reusable zip beats re-taping every time.
- Seal every gap, not just the obvious ones. Skirting gaps, keyholes, sockets on shared walls, gaps under doors, loft hatches and the space around pipework all leak fine dust.
- If the work is upstairs, tape off stairwell openings and consider hanging a second barrier at the bottom of the stairs as a belt-and-braces measure.
Extraction Beats Ventilation Every Time
Opening a window helps with fumes and heat, but it won't stop fine dust migrating through the house. Extraction is what actually removes it at source.
- Hire or buy a HEPA air scrubber and run it continuously inside the sealed zone. As a rough guide, you want it to turn the room's air over four to six times an hour.
- Position the scrubber so it pulls air away from the doorway you're using. Placing it facing the barrier just pushes dust at the one weak point in your containment.
- Use on-tool extraction with power tools — an M-class dust extractor on a sander or mitre saw catches the vast majority before it ever becomes airborne. Cheap L-class units are fine for general debris but not for silica or fine filler dust.
- Set up a box fan blowing gently out of a window in the work zone if you want to create negative pressure cheaply. Just don't rely on it as your only control.
- Empty extractor bags outdoors, into a sealed bag, and never shake a filter out inside the house.
Protect Floors, Vents and Walking Routes
Dust that lands on a floor gets walked everywhere. Dust that gets into a heating or ventilation system gets distributed to every room in the building.
- Lay heavy-duty floor protection — rigid boards or thick correx — on the route from the work zone to the door and the stairs.
- Switch off and tape over supply vents, extract grilles and MVHR terminals in the affected area. If the system has a filter, change it once the dusty work is finished.
- Remove soft furnishings, rugs and curtains from nearby rooms, or bag them. Fabric holds fine dust and releases it for weeks.
- Put down a tacky mat or a damp towel at the exit of the work zone, and keep a separate pair of boots that never leave that zone.
- Close internal doors elsewhere in the house and stuff a towel along the bottom — cheap, quick and surprisingly effective.
Clean Little and Often, Not All at Once
A single heroic clean at the end of the job is a losing battle. Ten minutes at the end of each working day keeps the whole house manageable.
- Never dry-sweep. It just lifts dust back into the air. Use a HEPA vacuum, and mist surfaces lightly with water before wiping.
- Wipe horizontal surfaces with a damp microfibre cloth, rinsing it in a bucket rather than under a running tap.
- Vacuum the containment barrier itself, and wipe down the zip area on the dust door — that's the spot most likely to transfer dust into the rest of the house.
- Bag waste inside the work zone, double-bag it, and carry it straight outside. Don't stack rubble in a hallway overnight.
Look After Yourself, and Finish the Job Properly
Your lungs are the last line of defence, and they're the one piece of kit you can't replace. Wear a well-fitted FFP3 mask for dusty work, and safety glasses — dust in the eye is a common and miserable injury. Change out of work clothes at the barrier rather than walking through the house in them, and shower before bed rather than taking dust upstairs with you.
When the dustiest phases are done, don't declare victory immediately. Run the air scrubber for another day, change the extractor and vacuum filters, wipe down skirting boards and door frames, and give the area one final HEPA pass once the fresh dust has had time to settle. Do that, and you'll be back in a genuinely clean home rather than one that merely looks clean until the sun comes through the window.
