Order of work
- Safety first. If the house was built before 1978, assume the old paint may contain lead: test it with an EPA-recognized kit or a certified inspector before you sand or scrape, and follow the EPA’s lead-safe work practices if it’s positive. Keep windows open or run a fan while you paint and while it dries.
- Clear and cover the room. Move furniture to the middle or out, lay the drop cloths, take off switch plates and outlet covers, and turn off power to any fixture you’ll paint around.
- Repair and clean. Fill nail holes and dents with spackle, let it dry, sand it flush, and wipe the walls down. Spot-prime the patches, or prime whole walls on new drywall, stains or a big color change.
- Paint the ceiling first, so drips land on walls you haven’t painted yet. Cut in along the edges with a brush, then roll it out in sections.
- Paint the trim with a brush, let it dry, then tape it off with painter’s tape. (Some painters do the trim last and tape the walls instead; either way each edge gets taped once.)
- Paint the walls: cut in along the ceiling, the trim and the corners, then roll each wall top to bottom while the cut-in edge is still wet. Wait for the recoat time on the can before the second coat.
- Pull the tape while the last coat is still slightly soft, at a low angle, and touch up any spots. Put covers and furniture back once the paint is dry to the touch.
Tools you’ll need
- Step ladder, and an extension pole for the roller on ceilings and high walls
- Putty knife, sanding sponge and a damp cloth for prep
- Screwdriver for switch plates and outlet covers
- 5-in-1 painter’s tool for opening cans, scraping and cleaning rollers
- Paint stir sticks and a bucket for mixing (boxing) cans together
- Safety glasses, gloves and a fan for ventilation
About this planner
Painting a room takes more than paint. A typical trip to the store also needs primer for patches or new drywall, a separate paint for the ceiling and the trim, tape for every edge, a roller cover for each product, brushes for cutting in, drop cloths and spackle. Forget one of them and the job stops halfway through a Saturday.
This planner works out the paint for the walls, ceiling and trim from your room’s size, subtracts doors and windows, adds primer if you need it, counts the tape, drop cloths, roller covers and brushes, and prices everything with your local numbers. The drawing shows the room from above and its four walls unfolded side by side, so you can see what gets painted and which edges get taped.
How to use it
- Measure the room’s length, width and wall height. For an L-shaped room, plan each rectangle separately and leave the shared opening out of one of them.
- Count the doors and windows. Count a patio door or a picture window as two.
- Choose the coats, check the coverage on your paint can, and say whether you’re painting the ceiling, the trim and whether you need primer.
- Open Your local prices, enter what your store charges, and print the project sheet to shop from.
How the quantities are worked out
Wall area = 2 × (length + width) × height − doors × 21 − windows × 15
Wall paint = wall area × coats ÷ coverage
Ceiling paint = length × width × coats ÷ coverage
Trim = (perimeter − doors × 3) + doors × 17 + windows × 16 ft, painted 4 in wide
Primer = primed area ÷ 300 sq ft per gallon (one coat)
Tape = perimeter + baseboard + casing, + 10%, in 180 ft rolls
Drop cloths = floor area ÷ 108 sq ft (9 × 12 ft), rounded up
Doors count as 3 × 7 ft and windows as 3 × 5 ft, the standard allowances paint makers use. Trim is counted on the room side only: baseboard around the room less each doorway, and casing up both sides and across the top of each door and around each window, with about 4 in of painted face per foot. Primer is figured at the low end of the 300–400 sq ft per gallon printed on common primers, because bare drywall and patches soak it up. Each paint is bought as whole gallons, plus one quart when what’s left over is a quarter-gallon or less.
Worked example
These are the planner’s starting values and the results they produce:
| Room length | 14 ft |
|---|---|
| Room width | 12 ft |
| Wall height | 8 ft |
| Doors | 1 |
| Windows | 2 |
| Coats of paint | 2 |
| Paint coverage per gallon | 350 sq ft |
| Ceiling | Paint the ceiling too |
| Trim | Paint baseboard and door & window casing |
| Primer | None – repainting walls in good shape |
| Wall paint, per gallon | $40.00 |
| Ceiling paint, per gallon | $35.00 |
| Trim paint, per gallon | $45.00 |
| Primer, per gallon | $25.00 |
| Any paint or primer, per quart | $18.00 |
| Painter’s tape, per 60 yd roll | $7.00 |
| Canvas drop cloth, 9 × 12 ft | $20.00 |
| Spackle and sanding sponge | $10.00 |
| Roller cover, each | $6.00 |
| Roller frame, tray and liners | $15.00 |
| Angled brush, each | $12.00 |
| Bought | Item | Buy | Cost |
|---|---|---|---|
| Ceiling paint (flat)0.96 gal for 168 sq ft × 2 coats | 1 gallon | $35.00 | |
| Wall paint2.09 gal for 365 sq ft × 2 coats; buy it all in one batch | 2 gallons + 1 quart | $98.00 | |
| Trim paint (semi-gloss)0.19 gal for 98 ft of trim (33 sq ft) × 2 coats | 1 quart | $18.00 | |
| Painter’s tape, 1½ in150 ft of edges + 10%; 60 yd (180 ft) rolls | 1 roll | $7.00 | |
| Canvas drop cloths, 9 × 12 ftCover the 168 sq ft floor; reuse them room to room | 2 | $40.00 | |
| Spackle and sanding spongeFor nail holes and dents; a quart tub does a room | 1 each | $10.00 | |
| Roller covers, 9 inOne per product: ⅜ in nap for smooth walls, ½ in for ceilings and light texture | 2 | $12.00 | |
| Roller frame and trayWith 2 tray liners, so each product gets a clean one | 1 set | $15.00 | |
| Angled brushes2½ in for cutting in walls and ceiling, 2 in for trim | 2 | $24.00 | |
| Estimated materials total | $259.00 | ||
Tips before you buy
- Buy all of the wall paint at once and pour the cans together in a bucket (“boxing”) so the color matches from wall to wall.
- Flat paint hides flaws on ceilings; eggshell or satin wipes clean on walls; semi-gloss stands up to scuffs on trim and doors.
- Wrap rollers and brushes tightly in plastic between coats instead of washing them; they’ll keep for a day.
- Write the paint name, color code and sheen on a piece of tape inside a switch plate. You’ll want it for touch-ups years later.
- Keep a little leftover paint in a small sealed jar for touch-ups, and take the rest to a paint recycling drop-off if your area has one.
Frequently asked questions
What do I need to buy to paint a room?
For a 14 × 12 ft room with 8 ft walls, one door and two windows, painting the walls, ceiling and trim with two coats: 2 gallons + 1 quart of wall paint, 1 gallon of ceiling paint, 1 quart of trim paint, one roll of painter’s tape, two 9 × 12 ft drop cloths, spackle, two roller covers, a roller frame and tray, and two angled brushes. At typical prices that comes to about $259.
How much does it cost to paint a room yourself?
Mostly the cost of the paint. In the same 14 × 12 ft room, the walls alone come to about $188 for paint and supplies at typical prices; adding the ceiling and trim brings it to about $259. The drop cloths, roller frame and brushes can be reused for the next room.
How much painter’s tape do I need for a room?
Add up the edges: along the ceiling, above the baseboard, and around each door and window casing. A 14 × 12 ft room with one door and two windows has about 150 ft of edges, so one 60-yard (180 ft) roll is enough.
Do I need to prime before painting?
Prime new drywall, patches, stains, glossy surfaces and big color changes such as dark to light. Repainting sound walls with a similar color usually needs no primer, or only spot priming. Priming the walls of a 14 × 12 ft room takes about 1.22 gallons at 300 sq ft per gallon, so buy a gallon and a quart.