We clean every surface the dust reached

We clean from the ceiling down

A renovation leaves dust on every flat surface in the house, and on plenty of the upright ones too. So we work from the top down. Ceiling fans and light fixtures come first, because whatever we knock loose up there falls onto everything below. Then the walls and door frames, then window sills and counters. Floors are always last. Clean the floor first and you clean it twice, and by the second time the dust has been walked into every corner.

Dust does not stay in the room where the work happened. It drifts into closets and kitchen cabinets, and it settles on picture frames two rooms away. If the kitchen got new cabinets, tell us, because every drawer holds sawdust from the install. We clean the appliances too, and after a kitchen job that means inside the oven and the microwave. Mini blinds get wiped one slat at a time. A feather duster would only move that dust down onto the sill.

Floors take longer than anything else in the house. Hardwood gets vacuumed with a soft brush along the grain first, so the dust comes up out of the gaps between the boards. Then it gets a damp mop, never a wet one, because standing water swells the edges of wood boards. Carpet takes several slow passes with the vacuum, since fine dust sinks deep into the pile. When it is done right, you can walk across the floor in socks and the soles come up clean.

• Ceiling fans and light fixtures dusted first
• Door frames and trim wiped by hand
• Window tracks and mini blinds cleaned out
• Inside of the oven and microwave cleaned
• Floors vacuumed before they are mopped

Drywall dust turns to paste when wet

Most of the dust after a renovation is joint compound, the mud used to fill the seams between sheets of drywall. Sanding it smooth throws off a powder finer than flour. Hit that powder with a wet rag and it turns back into mud, a thin white paste that smears across cabinets and dries into streaks. So every surface gets a dry pass first, with a vacuum or a dry cloth, and only then a damp wipe.

The vacuum matters as much as the order. Drywall dust is fine enough to slip through a household vacuum bag and blow back out the exhaust. A regular vacuum can put dust into the air faster than it pulls it off the floor. On a construction clean we empty and check the vacuum often, because a full bag or clogged filter loses suction fast. Window tracks and the grooves in door trim get the crevice tool, not a cloth.

Fine dust keeps coming down for a while after the sanding stops. Some of it is still hanging in the air when we arrive, too fine to see. On a big job, the counters can look clean when we leave and show a light film two days later. That is dust settling, and it is not a missed spot. A second, lighter clean a few days after the first one picks it up. Skip it, and the film ends up on your dishes and on every shelf you fill.

Plaster and drywall leave different dust

A lot of the older houses around Danvers and Salem still have plaster walls over wood lath. Tearing out plaster makes a coarse, gritty dust that is heavier than drywall powder. It also brings out whatever has been sitting inside that wall for a very long time. Plaster dust drops close to where it was made, so the room being worked on takes the worst of it. That grit scratches. We vacuum it off floors and sills before anything gets wiped, because a cloth dragged across it will scuff a finish.

Newer additions, and most houses built in the second half of the last century, have drywall instead. That dust behaves the opposite way. It is fine enough to float, so it follows the air up the stairs and under bedroom doors. A Cape with its bedrooms tucked under the roof is the classic case. Sand a wall in the kitchen and there will be dust on the upstairs dressers the next day. That is why we check the whole house, even rooms the contractor never set foot in.

In Lynn and Salem, plenty of renovations happen inside two-family houses and triple-deckers, where one unit gets redone while people live above and below it. Dust from that unit finds its way into the shared stairway and hall. It is worth having the stairs and the landing cleaned along with the rooms inside, because the neighbors see that dust first. Old stair treads hold dust in the worn dips and along the edge by the wall, so they get vacuumed before they get wiped.

Your heating system can spread leftover dust

Many North Shore homes heat with hot water baseboard, the long metal covers along the bottom of the walls. Inside each cover is a row of thin metal fins, and drywall dust packs into them. Nobody notices until the first cold night in the fall, when the heat comes on and the house smells like something is burning. That is the dust cooking on the fins. The fins get vacuumed during the clean, since a cloth cannot reach between them.

Homes with forced hot air have a different problem. The return vents pull air out of the rooms, and during a renovation that air is full of dust. It collects in the ducts, and when the furnace kicks on, it blows back out through the vents onto clean surfaces. The fix starts before we get there: the contractor should cover the vents while they sand. We vacuum every vent cover in the house, including the big return grilles. If a lot of dust got into the ducts, a duct cleaning company should go before we do.

The season changes the job, too. During a spring or fall renovation the windows can stay open, and some of the dust goes outside with the breeze. In a Massachusetts winter the house is closed up against the cold, so the dust stays inside and lands on the sills. Humid summer air makes the finest dust cling to glass and cabinet fronts as a dull film. After a renovation we clean the windows inside and out, tracks included. Grit left in the track of a window or patio door grinds every time it opens.