About this calculator
Stain, oil or sealer for a whole deck, including both faces of the railings and the steps, adjusted for weathered wood.
How it’s calculated
Area = deck + 2 × railing length × height × 1.2 (allowance for spindles) + steps. Amount = area × coats ÷ coverage. Rough or weathered wood is assumed to drink about a third more.
Worked example
With these inputs:
- Deck length
- 16 ft
- Deck width
- 12 ft
- Railing length
- 28 ft
- Railing height
- 36 in
- Steps
- 3
- Wood condition
- New / smooth
- Coats
- 2
- Coverage (sq ft per 3.78 L can)
- 250
the result is:
- Stain needed
- 12.4 L
- Deck surface
- 192 sq ft
- Railing (both faces)
- 201.6 sq ft
- Total area
- 408.4 sq ft
Tips from the trade
- Clean and brighten the wood first. Stain won’t stick to grey fibres.
- Do a water-drop test: if water beads, the wood isn’t ready to take stain.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and the building code adopted in your province before ordering.