How Much Stain or Paint Do I Need for a Fence?
Bare timber drinks the first coat, so fence stain almost always goes further on paper than in the tin. Here is how to estimate the litres or gallons you need, both sides, with the right coverage for rough-sawn boards.
By the Calculate My Reno Team / Published
Skip to the tool
Open the Fence Calculator
Staining or painting a fence is cheap material over a lot of area, and the area is easy to underestimate because most fences have two sides. A quick calculation saves a half-finished fence and a second trip.
The method
Stain and paint are sold by coverage rate - the area one litre or gallon covers. So the estimate is area divided by coverage, times the number of coats:
area = length × height × sides
material = area ÷ coverage × coats
A fence is a tall thin rectangle, so use the run length from your fence calculator and multiply by the height. Staining both faces? Multiply the area by two.
Coverage and coats
The coverage on the tin assumes smooth timber and one coat. Real fences rarely match it:
| Factor | Effect on the count |
|---|---|
| Both sides | Doubles the area |
| Rough-sawn timber | Lose a quarter to a third of coverage |
| Bare new wood, first coat | Soaks up the most - buy generous |
| Re-coat on sealed wood | Goes furthest - closest to the tin figure |
| Posts, rails, caps | Add a little extra area |
For a new fence, plan on two coats and use the lower end of the coverage range.
Worked example
A 20 m run, 1.8 m high, stained both sides, coverage 6 m2 per litre, two coats:
- Area: 20 × 1.8 × 2 = 72 m2.
- Per coat: 72 ÷ 6 = 12 litres.
- Two coats: 12 × 2 = 24 litres.
In imperial, a 60 ft run at 6 ft high, both sides, is 720 sq ft; at 250 sq ft per gallon over two coats that is 720 ÷ 250 × 2 = about 6 gallons.
A few tips
- Stain the bare ends and any cut faces first - they soak up the most and rot first if left.
- Buy all of one colour batch at once so the shade matches across the whole run.
- A pump sprayer is faster on rough-sawn timber, but back-brush the first coat to push it into the grain.
- Budgeting the whole job? Stain and paint are a small line next to the timber - see how much does a fence cost.
Frequently asked questions
How much stain do I need for a fence?
Work out the area (length times height, times two if you stain both sides), then divide by the coverage rate on the tin. A 20 m run at 1.8 m high, both sides, is 72 m2; at 6 m2 per litre that is 12 litres a coat. Rough-sawn timber and a thirsty first coat can cut coverage by a third, so round up.
How much paint do I need to paint a fence?
Use the same area-divided-by-coverage method as stain, but paint usually needs a primer or first coat plus one or two topcoats, so multiply by the number of coats. For a 72 m2 fence at 8 m2 per litre over two coats, that is 72 ÷ 8 × 2 = 18 litres. Smooth, previously painted boards cover better than bare rough timber.
How many coats of stain does a new fence need?
A new timber fence usually takes two coats of stain - the first soaks deep into the dry, thirsty wood and the second builds the colour and protection. Some penetrating oils are sold as a single saturating coat. Re-coats every few years usually need just one coat as the timber is already sealed.
Does rough-sawn timber use more stain?
Yes, noticeably. Rough-sawn and weathered timber has more surface area and soaks up far more than smooth, planed boards - it is common to lose a quarter to a third of the stated coverage. When the tin gives a range, use the lower (rougher) figure for a new fence and round up.