SettingsSettings for this calculationUS
How many door leaves are being painted.
Count each leaf: a pair of double doors is two. Cupboard doors count too if they are being painted with the rest of the woodwork — enter their size below as an average.
One face of one door: its width × its height.
A standard interior leaf of 826 × 2040 mm (about 2 ft 8 in × 6 ft 8 in) is 1.7 m², about 18 sq ft. A panelled door has more surface than its outline because of the mouldings — add a tenth for a four-panel door.
Whether both sides of each door are painted.
A door is usually painted whole, both faces and edges, when the room is decorated. Choose one face where the other side belongs to a room being done in a different colour or at another time.
The length of frame and architrave being painted, both sides of every door.
Each side of a door frame runs up both legs and across the head: twice the door height plus its width. A standard door has about 4.9 m (16 ft) of frame on each side, so about 10 m (32 ft) for both.
The width of painted surface on the frame, measured round its profile.
Wrap a tape round what gets painted: the architrave's face and its edge, and the exposed part of the lining. About 150 mm (6 in) is typical for a standard architrave and lining; a deep reveal in a thick wall is much more.
The length of skirting board being painted.
Round the room, less the doorways. Include any skirting on the sides of a chimney breast or into alcoves, which a room's length and width do not show.
The height of the skirting plus its painted top edge.
A 100 mm (4 in) skirting board with its moulded top is about 120 mm (4¾ in) of painted surface; a tall 170 mm (6¾ in) Victorian skirting about 190 mm (7½ in).
Top coats over primed or previously painted woodwork.
Two coats is usual for gloss or satin over an undercoat; a one-coat gloss is sold for repainting in a similar colour. Bare timber needs a primer and knotting first, which are separate products.
The area one unit of your trim paint covers per coat — printed on the tin.
Read it off the tin. An American or Canadian enamel usually claims somewhere between 300 and 450 sq ft to the gallon; a British or European gloss, satin or eggshell often claims 16 or 17 m² to the litre, which is well over 600 sq ft to the gallon. Ten square metres a litre, the default, is at the generous end of the first and the cautious end of the second. One-coat and high-build glosses go on thicker and cover less than either.
Woodwork paint needed
0.3565 gal
- Door faces
- 36.6 ft²
- Frames
- 16.5 ft²
- Skirting
- 18.21 ft²
- Area to paint, one coat
- 71.31 ft²
They open the calculator with your figures already in it
Woodwork Paint Calculator: 0.3565 gal — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
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How this was calculated
Formula source(s)
- No published standard governs joinery paint quantities. The page applies the coating identity — paint = area × coats ÷ spread rate — to door leaves measured by face, and to frames and skirting measured as run × painted girth
- Trim paints are rated per coat on primed, smooth timber: commonly about 300 to 450 sq ft per gallon (7.4 to 11 m² per litre) for North American enamels, and often up to 16 or 17 m² per litre for UK and European glosses, satins and eggshells; the product's own tin is the figure to use
Inputs used
- Doors
- 1
- Area of one door leaf
- 18.3 sq ft
- Faces painted
- Both faces of each door
- Door frame run
- 33 ft
- Frame girth
- 6 in
- Skirting run
- 46 ft
- Skirting girth
- 4.75 in
- Number of coats
- 2
- Spread rate
- 400 ft²/gal
Intermediate steps
- Door faces
- 36.6 ft²
- Frames
- 16.5 ft²
- Skirting
- 18.21 ft²
- Area to paint, one coat
- 71.31 ft²
What this calculation does not cover
- Door leaves are measured by their outline and frames by their girth. A panelled door has more surface than a flush one of the same size because of its mouldings, door edges are not counted, and a deep reveal adds lining an ordinary girth does not — add a tenth for panelled doors.
- Windows are not included. Timber window frames, sashes and sills are painted with the woodwork but vary too much in profile to take from a window's size; measure them as a run and girth and add them to the frame run.
- Primer, undercoat and knotting on bare or stripped timber are separate products and are not in this figure.
- The figure is paint that reaches the timber. Nothing is added for the tin, the brush or cutting in round glass and hinges — add it as an allowance.
- Doors, frames and skirting in housing built before lead paint was restricted are where an earlier lead-based layer is most likely, and the risk is in the preparation rather than the painting: sanding or heat-stripping turns a sound film into dust or fume that is especially harmful to children and in pregnancy. Test old woodwork before abrading or stripping it. No quantity on this page depends on it.
Estimated cost — your price
This site holds no price list for this material — local prices vary too much to publish honestly. Enter your supplier's price and the result is costed with it.
Part of bigger jobs
This trade is one line of several job takeoffs. Run the whole job and every other trade comes back with it, off the same measurements.
Or plan the space itself: measure it once, doors and windows included, and this figure comes back worked out on that space, with what goes with it.
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Computed in your browser — nothing you enter is uploaded. Presented in US customary units and US trade terminology. Where a formula follows a published standard, that standard and its edition are cited beside it on this page; where none governs, the page says so. Local amendments override model codes — verify against the code in force where you build.
Sources checked 2026-09-17 · v1.0.0
Regulatory standards & verification citations2
- No published standard governs joinery paint quantities. The page applies the coating identity — paint = area × coats ÷ spread rate — to door leaves measured by face, and to frames and skirting measured as run × painted girth
- Trim paints are rated per coat on primed, smooth timber: commonly about 300 to 450 sq ft per gallon (7.4 to 11 m² per litre) for North American enamels, and often up to 16 or 17 m² per litre for UK and European glosses, satins and eggshells; the product's own tin is the figure to use
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Your workspace
Most jobs need more than one number. Add the calculators you need next and they open right here, underneath this one — your figures stay on screen and nothing is lost to a page change.
Protection this work requires
- Stop and check first. Paint under later coats in older housing can be lead-based, and sanding or heat-stripping it produces lead dust that is especially harmful to children and to anyone pregnant. Test before you disturb it — this is a job for a tested, controlled method, not a better mask.
Tools and safety for this job
To roll and cut in two coats, prepare a surface for paint and strip an old coating off timber. Generic types, no brands, no prices.
- Hardwood dust is a recognised carcinogen: extract at the tool and wear a P2/N95 respirator when cutting or sanding indoors.
- Joint-compound dust is very fine and travels: a P1/FFP1 mask is the minimum, and a damp-sponge finish avoids most of it.
- A dust mask does nothing about solvent vapour: ventilate through, and use an organic-vapour (A1) cartridge respirator in an enclosed room.
- Most fatal falls on small jobs are from under three metres: use a tower or a ladder tied at the top, and never work off the top two rungs.
Show the 13 tools this job needsHide tools
Essential
Brushes
Dust sheets and masking
Filling knife
Random orbital sander
Roller frame, sleeves and tray
Scraper
Shave hook
Recommended
Caulking gun
Dust extractor or vacuum with a fine filter
Extension pole
Heat gun
Pole sander
Step ladder
Also needed as materials: abrasive discs, caulk and sealant cartridges, masking tape, plastic sheeting, roller sleeves, sanding screens or paper.
what each painting tool is for, and the spec that decides which to buy where one does.