Paint Calculator
Calculate exactly how many litres of paint you need for any room or surface. Accounts for doors, windows, coverage rate, and the number of coats.
Painting Guide
Paint Coverage Rates
Coverage varies significantly by paint type and surface. Standard emulsion (vinyl matt, silk): 10–14 m² per litre. Premium emulsion (Farrow & Ball, Little Greene): 10–12 m² per litre. Masonry paint: 5–8 m² per litre. Gloss or satin (woodwork): 14–18 m² per litre. Always check the tin — the stated coverage assumes smooth, sealed surfaces. New plaster, rough or porous surfaces, and highly absorbent substrates will reduce coverage by 30–50%. Use a good primer coat on new plaster and first-time pain
How Many Coats?
One coat: only suitable for touch-ups, re-painting the exact same colour, or if using a paint-and-primer combination on a well-prepared surface. Two coats: standard for most painting projects — gives even coverage and better depth of colour. Three coats: needed for dark colours over light (especially with deep colours like red, dark blue, and black which have poor opacity), new plaster (one coat to seal plus two finish coats), and highly absorbent surfaces. Using cheap paint and applying three c
Preparation is the Work
Professional decorators spend 60–70% of their time on preparation — filling, sanding, cleaning, taping. The most common DIY painting failure is inadequate prep. Fill all holes and cracks with Polyfilla, sand smooth when dry, and prime the filled areas. Wash walls with sugar soap to remove grease, nicotine, and general grime — paint will not adhere properly to dirty surfaces. Sand gloss woodwork with 120-grit before repainting — gloss needs a key to accept new paint. Tape edges with low-tack pain
Paint Finishes for Different Surfaces
Matt: ceilings and walls in low-traffic areas — hides imperfections well but not washable. Eggshell or washable matt: the modern compromise — looks close to matt but can be wiped clean. Suitable for most walls. Silk: more sheen, highly washable, shows wall imperfections more. Good for kitchens, bathrooms, hallways. Soft sheen: between eggshell and silk. Satinwood: for woodwork (doors, skirting, window frames). Gloss: traditional high-sheen woodwork finish. Water-based (acrylic) paints have large
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