How many patio heaters do I need?

A standard gas patio heater covers approximately 10-15m² effectively. For a 30m² patio area, you would need 2-3 heaters depending on temperature and desired warmth level. Place heaters where guests congregate rather than spacing evenly.

How much gas does a patio heater use?

A standard gas patio heater uses approximately 0.8-1.0 kg of propane per hour on the highest setting. A 13kg gas bottle will last approximately 13-16 hours. On a lower setting, consumption drops to about 0.4-0.6 kg per hour.

Gas or electric patio heaters?

Gas heaters are more powerful and work anywhere but need ventilation and gas bottles. Electric infrared heaters are cheaper to run, instant warmth, and lower maintenance but need a power supply and cover less area. Gas is better for larger open spaces.

How much does it cost to run patio heaters?

Gas patio heaters cost approximately £2-£3 per hour per heater on high. Electric infrared heaters cost about £0.50-£0.80 per hour at current electricity rates. For a 4-hour event with 3 gas heaters, expect £25-£35 in gas costs.

Outdoor Heating Calculator — Heaters & Running Cost

Calculate how many outdoor heaters you need and their running cost for your event.

Outdoor Area

Total area where guests will gather. One gas heater warms ~10-15 m² effectively, so size it to the seating/standing zone, not the whole garden.

Expected Temperature

Forecast evening low for your event. Below 5°C needs ~30% more heaters; below freezing ~60% more.

Desired Warmth LevelMinimal just takes the chill off (fewer heaters); Warm keeps a seated crowd cosy (~30% more heaters).

Heater TypeGas/pyramid heaters need bottles but cover open space; electric needs a power supply but is cheaper to run; fire pits burn logs.

How We Calculate This

The calculator estimates heater count from area, temperature, and desired warmth, then calculates fuel requirements and costs.

Coverage Estimates

Gas patio heater: ~12m² coverage, 0.9 kg/hr gas
Pyramid heater: ~15m² coverage, 1.0 kg/hr gas
Electric infrared: ~8m² coverage, 2kW
Fire pit: ~10m² coverage, ~£3.50/hr in logs per pit

Coverage is adjusted for temperature and desired warmth level. Gas is sold in whole bottles, so the Total Cost rounds gas up to full 13kg bottles, while the per-hour Running Cost reflects the fractional gas actually burned.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Adjust quantities based on your guests and event type.