Firewood Calculator NZ

This calculator works out how much firewood a New Zealand household needs for winter and what that wood should cost, so you can order the right amount rather than running short or over-ordering and wasting money. You enter how many nights a week you typically burn the fire, how many weeks the heating season lasts, and roughly how many cubic metres a single night's fire uses, and the calculator estimates your total seasonal volume. You then enter the price per cubic metre charged by two suppliers, and the tool returns the estimated volume needed for the season, the total cost from each supplier, and how much you would save by choosing the cheaper one. This makes it easy to compare quotes on a genuine like-for-like basis, rather than being caught out by suppliers who sell by different measures, such as a thrown cubic metre versus a stacked one. When buying, confirm which measure a price refers to, and choose dry, well-seasoned wood over green wood, since it burns hotter, produces less smoke, and gives you more heat for your money. Storing wood under cover once delivered helps keep it that way. The cubic metres per night figure is a rough guide and will vary with your burner and house size, so treat the results as an estimate for planning rather than an exact order quantity.

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$
$
3.6 m3
estimated firewood needed for the season
Cost with Supplier A$468
Cost with Supplier B$540
You save with the cheaper$72

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.

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Frequently asked questions

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.