Interior Painting serving Cambridge and Metro West MA.

Census estimates put 47.0% of Cambridge's housing units in buildings from 1939 or earlier, and the median year built across the city is 1950. Another 20.9% of units date from 1940 through 1979. Taken together, 67.9% of the city's homes were built before 1980, and anything finished before 1978 can carry lead paint somewhere under the current color.

That history shapes an interior job more than the color card does. A room built before 1940 may have plaster patched more than once, trim carrying many coats, or a ceiling finish that modern latex does not grip, so the first step is finding out what is already on the surface before anything new goes on top.

Plaster walls and ceilings

In houses of that age, walls and ceilings may still be original plaster on wood lath, or a past renovation may have swapped them for drywall. Sound plaster takes paint well, but it moves with the seasons and shows hairline cracks, nail pops where lath has shifted, and bulges where the keys behind it have let go.

Hairline cracks can be opened slightly, filled and primed. Loose areas need to be reattached with plaster washers or cut out and patched before they are painted, because new paint adds weight and will not hold a failing section in place. A ceiling that peels in sheets may have an old calcimine or distemper layer underneath that latex will not bond to; that layer has to be washed off or sealed with a primer made for it.

• Crack repair and skim patches on plaster
• Sealing chalky or water-stained ceilings before topcoats
• Scraping and sanding built-up trim, doors and window casings
• Washable finishes for halls, kitchens and baths

Lead dust inside the house

Indoors, the federal Renovation, Repair and Painting rule covers paid work in pre-1978 housing that disturbs more than six square feet of paint in a room. Sanding a window sill, scraping a door jamb or cutting into old trim can easily cross that line. Lead-safe work means plastic over floors and furniture, containment at doorways, misting instead of dry sanding, and HEPA vacuuming and wet cleaning before the room is handed back.

Massachusetts goes further for families with young children: the City of Cambridge notes that under state law any apartment or single-family home with an occupant under six must be deleaded, and that a deleaded home is lead-safe, not lead-free. Deleading is a separate legal process, not the same thing as repainting. Our lead-safe painting page explains the difference, and income-eligible owners can ask the city's Home Improvement Program about loans for lead hazard work.

Rentals, owner units and turnovers

Two out of three occupied homes in Cambridge are rented (66.5%, by census estimate), and for a landlord, a turnover repaint has a fixed window: the old lease ends, the new one starts, and patching, priming and two coats all have to fit in between. Picking one durable wall color and one trim color for every unit in a building makes touch-ups far simpler the next time around.

Owner-occupied rooms are a different job. Furniture has to be moved and covered, rooms are done in sequence so the house stays livable, and drying time matters for bedrooms that need to be slept in that night. Our guide to getting a house ready for interior painting lists what to clear and protect beforehand.

Scheduling around the city's work-hour limits

Cambridge restricts construction noise that can be heard 50 feet from the lot line to 7 a.m.–6 p.m. on weekdays, with a 9 a.m. start on Saturdays and holidays, and Sunday construction needs Police Department approval. Brushing and rolling are quiet, but power sanding and running a vacuum outside the building are not, so the loud steps belong inside those windows.

Interior painting also works through the winter, when exterior work is limited; see our notes on painting indoors during the cold months. Homes in Mid Cambridge, Cambridgeport, North Cambridge and every other part of the city can be looked at on a free on-site visit.