How much gloss paint do I need per door?

A standard UK internal door is approximately 1.5 m² (1981mm × 762mm). At 16 m²/L coverage for gloss paint, one door needs about 0.09 L per coat, or 0.19 L for two coats. A 750ml tin covers roughly 4 doors with two coats. Don't forget the door frame — each frame adds approximately 0.5 m² per linear metre.

Do I need undercoat before gloss?

Yes, undercoat is strongly recommended before gloss paint. Undercoat provides better adhesion, builds opacity (especially when changing colours), and gives the gloss topcoat a smooth, even base. On bare wood, use a primer first, then undercoat, then gloss. On previously glossed surfaces in good condition, a light sand and two coats of gloss may suffice.

What is the coverage rate for gloss paint?

Gloss and satinwood paint typically covers 16 m²/L on smooth prepared surfaces. Eggshell covers slightly less at 14 m²/L. These rates assume a properly prepared surface with undercoat. Bare or absorbent wood will use significantly more paint. Water-based gloss may have slightly lower coverage than solvent-based.

How many coats of gloss do I need?

Two coats of gloss over undercoat is the professional standard. One coat of gloss rarely gives full coverage or a good sheen. When using water-based gloss, two coats are essential as the first coat can look patchy. Apply thin, even coats — thick coats cause drips and take longer to dry.

Should I use water-based or oil-based gloss?

Water-based (acrylic) gloss is now the standard in the UK due to VOC regulations. It dries faster (1-2 hours vs 16 hours), has less odour, and yellows less over time. Oil-based gloss gives a harder, shinier finish but takes longer to dry and yellows. For the highest sheen on doors, oil-based is still preferred by many decorators.

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Gloss Paint Calculator — Doors, Frames & Skirting

Calculate gloss, satinwood, or eggshell paint for doors, frames, skirting boards, and window frames. Includes undercoat quantities.

Number of Doors

Standard door = 1.5 m² each

Door Frame Length

Total linear metres of all frames

Skirting Board Length

Total linear metres of skirting

Window Frame Area

Total window frame area

Paint Finish

Number of Topcoats

2 coats recommended

Tin Size

Price Per Tin (optional)

How We Calculate This

This calculator adds up the areas of all woodwork items — doors, frames, skirting, and window frames — then calculates the gloss and undercoat paint required.

The formula

Door area = Number of doors × 1.5 m²

Frame area = Frame metres × 0.5 m²/m

Skirting area = Skirting metres × Height (m)

Gloss litres = (Total area × Coats ÷ 16 m²/L) × Wastage

For example, 4 doors (6.0 m²) + 8m frames (4 m²) + 20m skirting (3 m²) = 13.0 m². Gloss: 13.0 × 2 ÷ 16 = 1.63 L + 10% waste = 1.79 L → 1 × 2.5L tin. Undercoat: 13.0 ÷ 14 = 0.93 L + 10% = 1.02 L → 1 × 2.5L tin.