Interior Painting Cost: Materials vs Labour

Measure wall length × height for each wall, subtract large openings if you want to be tidy, and do ceilings as a separate rectangle. Two coats and realistic coverage matter more than buying the cheapest tin. New drywall, stained walls, or a jump from dark to light usually need primer or an extra coat — that is product, not optimism.

Worked example: a room with 160 sq ft of wall and 120 sq ft of ceiling. At roughly 350 sq ft per gallon per coat (a planning figure — check your tin), walls need about 160/350 ≈ 0.46 gallon per coat; two coats ≈ 0.9 gallon. Ceiling at one or two coats adds its own line. You still buy whole gallons or litres. The Paint Calculator keeps the arithmetic honest before you round up at the counter.

US jobs think in gallons and square feet; UK jobs in litres and square metres. Pick the system you will buy in. Coverage claims assume ideal surfaces — real walls with texture or repairs use more film. Do not convert halfway through in your head.

Prep (filling, sanding, caulking), masking, cut-in quality, ceiling work, and furniture moving often dwarf the cost of the paint itself in a contractor quote. Empty rooms paint faster than furnished ones. High trim detail, stairwells, and wallpaper stripping slow the job more than square footage alone suggests.

Colour changes show every defect. A “same colour refresh” with light prep is a different labour day from a deep feature wall over patched plaster. Ask quotes to describe prep level in plain language: spot fill, full skim touch-up, or full reboard where the Drywall Calculator would already have predicted sheet counts.

Access matters. High ceilings, awkward landings, and rooms that must stay in use overnight change crew size and hours. A low per-square-foot number that assumes a vacant clear room will not survive a lived-in family house.

Enter paint, primer, tape, filler, and sundries in the Cost Estimator, then add a labour allowance if you have an hourly or per-room quote. Keep a contingency for repairs that appear once old paint comes off — hairline cracks and soft spots are normal in older US and UK homes.

National averages for “cost per square foot to paint” hide prep differences. Prefer itemised scope: rooms, coats, whether ceilings and trim are included, who moves furniture, and who supplies materials. The Paint Cost Calculator helps when you want a materials-focused money view beside the gallon count.

If the contractor supplies paint, ask for the product grade or sheen list. “Premium” without a name is not a specification. If you supply paint, write that into every quote so labour-only bids stay comparable.

Primer on new drywall, tannin-stained timber, or sealed stains is an extra product line. Burying it inside “paint” makes DIY budgets look artificially cheap next to a pro who primes properly.

Ceilings usually want a flat ceiling formulation; walls take a washable sheen suited to the room. Kitchens and bathrooms may need more scrubbable finishes. Calculate ceiling area separately from walls in the Paint Calculator so you do not under-buy the white that shows every lap mark.

Trim, doors, and frames are slow, brush-heavy work. A quote that is cheap on walls but silent on doors is incomplete. Decide whether doors are in scope before you compare totals.

DIY saves labour but costs time and risk of visible lap marks, especially on ceilings and in hard daylight. Hiring makes sense when stairs, high work, or major colour changes need experience — still use your own gallon count to check the material line.

If you DIY, budget primer, tape, drop cloths, brushes that actually hold an edge, and a second day for cut-in touch-ups. Consumables are easy to forget when comparing a “paint only” estimate to a full contractor quote.

For rental turnovers or resale timelines, labour speed often outweighs gallon savings. Decide with the calendar and the finish quality you need, not only the tin price on the big-box shelf.

Line up inclusions: walls, ceilings, trim, doors, primer, furniture moving, flooring protection, and number of coats. A bid that skips ceilings can look cheaper until you add them back.

Ask whether patch-and-paint of damaged drywall is included or charged as extras. If walls need reboarding, estimate sheets with the Drywall Calculator first so you know whether you are buying a paint job or a mini renovation.

Payment timing and recoat windows matter in humid weather. Written scope beats a handshake price that grows when the first wall reveals nicotine stain.

List each room’s wall and ceiling area, coats, and whether primer is planned. Run the Paint Calculator, round up to whole containers, and price that materials list. Put the same list next to each contractor’s materials assumption.

If their gallon count is far below yours, ask which areas or coats they excluded before you assume you over-measured. If theirs is far above, they may be pricing heavy prep coats or a safer coverage rate — that can be good practice, not padding, when walls are rough.