How much firewood do I need for winter?

It depends on how often you burn and for how long. Many households use a few cubic metres a season. This calculator estimates your seasonal volume from how often you light the fire.

How is firewood sold in New Zealand?

Often by the cubic metre, sometimes thrown or stacked, which can differ. Compare suppliers on a consistent measure, and buy dry, seasoned wood, which burns far better than green wood.

Why does dry firewood matter?

Dry, seasoned wood produces more heat and less smoke than wet or green wood, so it is better value and better for air quality. Buying ahead and storing it under cover helps.

Firewood Calculator

This calculator helps New Zealand households that heat with a wood burner work out how much firewood they need for the season and what it should cost, avoiding both running short in winter and overpaying. You enter your burner use and the way firewood is sold, and the tool estimates the volume required and the cost at the prices you enter, helping you compare suppliers selling by different measures. The breakdown shows the estimated seasonal volume, the cost, and a comparison across suppliers, bringing clarity to a purchase that is often guessed at, and helping you buy the right amount of dry wood at a fair price.

Nights burning per week

Weeks in the season

Cubic metres per night

Supplier A ($/m3)

Supplier B ($/m3)

0 m3

estimated firewood needed for the season

Cost with Supplier A$0

Cost with Supplier B$0

You save with the cheaper$0

Cubic metres per night is a rough guide; a typical evening fire uses a small fraction of a cubic metre. Firewood is sold thrown or stacked, which differ, so compare on the same measure. Buy dry, seasoned wood and store it under cover. Estimate only.

How it works

The calculator estimates how many nights you burn over the season, which is your nights per week times the weeks, then multiplies by the cubic metres you use per night to estimate the total volume. It then prices that volume against the two suppliers you enter, so you can see the cost difference and order the right amount in one go rather than topping up at a premium mid-winter.

Worked example

Burning 5 nights a week for 18 weeks is 90 fires. At 0.04 cubic metres each, that is about 3.6 cubic metres for the season. At $130 a cubic metre that is roughly $468, while a $150 supplier would cost about $540, so the cheaper supplier saves around $72.

Related calculators

Home Heating Cost Calculator: compare heating.
Electricity Cost Calculator: power costs.
Cubic Meter Calculator: work out volume.
Budget Calculator: household budget.

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