Wood Finishing Guide: Varnish, Oil, Paint

Choose the right finish, calculate the litres you need and apply it like a pro.

Which finish?

Finish	Look	Durability	Best for
Varnish	Glossy/satin film	High	Tabletops, floors
Oil / hardwax	Natural, low sheen	Medium	Furniture, tool handles
Stain	Colours without film	Low (needs topcoat)	Changing wood colour
Paint	Opaque film	High	Cabinets, painted furniture

Area = length × width × number of surfaces
Litres = area × coats / coverage (m²/l)
Buy = litres × (1 + margin%)

Typical coverage: varnish/paint 8–12 m²/l, stain 8–15 m²/l, oil 10–18 m²/l per coat.

A tabletop 1.8 × 0.9 m, 3 coats of varnish at 10 m²/l, 10% margin:

Area = 1.62 m²
Litres = 1.62 × 3 / 10 = 0.49 l
Buy = 0.49 × 1.10 ≈ 0.54 l → buy 0.75 l

Use the wood finish calculator to size your can before buying.

Estimate varnish, paint, stain and oil quantities for your wood surfaces and coats.

The simple formulas to convert board dimensions into cubic meters and board feet.

The North American lumber unit explained with examples and conversions.

Understand waste percentages, why they vary and how to price them into your projects.

Layout strategies to reduce waste and speed up cutting on your panel saw.