Fence Paint Calculator

Fence paint or stain coverage depends on the product and the condition of the timber. Most fence paints cover 4–6 m² per litre on rough-sawn timber (which absorbs more) and 8–10 m² per litre on smooth or previously painted timber. Water-based fence paints dry in 1–2 hours; solvent-based treatments take 4–6 hours.

This calculator measures the total fence area: panel height × total run length × number of painted sides (usually one or two). For closeboard or overlap panels, the overlapping boards create extra surface area — the calculator adds 15–20% to account for this. Posts and gravel boards are included as additional area.

Enter fence dimensions, number of sides to paint and number of coats. The calculator shows total area, litres needed and tin sizes. Most UK fence paints are sold in 5 L and 9 L tins. One coat is usually sufficient for maintenance; two coats are recommended for bare or weathered timber for best coverage and longevity.

How much fence paint do you need? Coverage rates: typical fence stain 8-10 m²/litre per coat. Two coats recommended for new wood. Sample 12m × 1.8m fence × 2 sides = 43.2 m² × 2 coats = 86.4 m² coverage needed. At 9 m²/L = 9.6 L paint. Bigger bucket more economical: 5L tins typically £25-£50 for own-brand; £30-£60 branded. UK favorites: Ronseal Fence Life Plus (5L £25-£35); Cuprinol Garden Shades (2.5L £20-£30); Sadolin Superdec (5L £40-£60).

UK fence stain types. Water-based: easier cleanup, low odour, breathable, 7-10 year life. Solvent-based: deeper penetration, longer-lasting (10-15 years), strong smell. Oil-based: traditional, repels water best, 5-8 year cycle. Decorative coloured stain (Cuprinol, Sadolin): wide colour range, semi-transparent. Solid colour fence paint: opaque, hides imperfections. Always check 'shed and fence' specification — some products different from garden furniture stains.

When to paint your fence. Best: dry warm weather, 10-25°C, no rain forecast 24-48 hours. Spring (April-May) and early autumn (September): UK ideal seasons. Avoid: hot direct sun (paint dries too fast); freezing temperatures (poor adhesion); wet timber (won't bond). New timber: wait 4-6 months for moisture to escape before painting. Re-paint cycle: every 3-5 years for water-based; 5-7 years for premium solvent-based.

Application technique. Clean fence first: brush off dirt, moss, algae. Treat mould with specialist cleaner (Cuprinol Mould Remover). Sand smooth if previously painted. Apply with: brush (best for textured surfaces); roller (faster on smooth panels); HVLP sprayer (fastest but messier — protect plants). Two thin coats better than one thick. Don't paint in direct sun. Allow 2-4 hours between coats. Total project time 30m² × 2-side fence: 3-5 hours one person + drying.

Cost vs longevity. Budget fence paint £20/5L: lasts 3-5 years. Premium £50-£60/5L: 7-10 years. Sample 12m fence: budget total cost over 20 years = £100 (5 repaints) × 3 hours labour each = 15 hours of work. Premium: £180 (3 repaints) × 3 hours = 9 hours. Premium typically wins on lifetime cost + less labour. Best UK premium choices: Ronseal Fence Life Plus, Cuprinol Ducksback (5 year guarantee), Sadolin Superdec (10 year on suitable timber).