How Many Heaters Do You Need? Sizing Bromic Heat for Patios, Pergolas and Restaurants
The most common heater mistake is buying one big heater for a space that needs two smaller ones. Radiant heat works best when it covers the seating evenly, so sizing is really about coverage and placement. Here is the simple method we use with customers.
Step 1: Measure the area people use
Measure only where people sit or stand, not the whole yard. A 12 by 16 foot dining area is 192 square feet; a lounge corner around a sectional might be 10 by 12, or 120 square feet.
Step 2: Match it to heater coverage
Each Bromic heater warms roughly this much area (from our product specifications):
| Heater | Approx. heat area |
|---|---|
| Platinum Electric 2300W | 65 sq ft |
| Platinum Electric 3400W | 108 sq ft |
| Platinum Electric 4500W | 143 sq ft |
| Tungsten Electric 2000W / 3000W | 65 / 100 sq ft |
| Tungsten Electric 4000W / 6000W | 130 / 160 sq ft |
| Eclipse Electric 2900W | 121 sq ft |
| Platinum or Tungsten Gas 300 series | 160 sq ft |
| Platinum or Tungsten Gas 500 series | 215 sq ft |
Divide your area by the coverage and round up. In practice, two smaller heaters on opposite sides often feel more even than one large heater on one side.
Worked examples
- Covered dining patio, 12 x 16 ft (192 sq ft): two Platinum Electric 3400W (108 sq ft each), one at each end, or a single 500 series gas heater if you have the headroom.
- Pergola lounge, 10 x 12 ft (120 sq ft): one Tungsten Electric 4000W or Platinum 4500W centered over the seating.
- Long balcony, 6 x 20 ft (120 sq ft): two smaller heaters spaced along the length, such as two Platinum 2300W, rather than one big heater at one end.
- Restaurant patio, 30 x 40 ft (1,200 sq ft): six to eight heaters in an even grid, controlled in zones so you heat only the sections that are seated.
Step 3: Adjust for your conditions
- Open or windy: size up, or add a heater. Wind carries warmth away from people faster.
- Fully covered with walls on two or three sides: the listed coverage usually feels generous.
- Colder climates or long winter use: lean toward the larger model in each line.
- Higher mounting: heat spreads wider but gentler, so allow more heaters if you mount well above the minimum height.
Step 4: Place heaters where people sit
Center ceiling heaters over tables, angle wall heaters toward seating, and keep within the minimum heights and clearances in our installation guide. Plan controls at the same time: zoning several heaters on separate channels, or adding dimmers, lets you use only the heat you need. See our guide to Bromic controls.
Heaters by size
Frequently asked questions
How many square feet does a patio heater cover?
Bromic heaters range from about 65 square feet (Platinum Electric 2300W) to about 215 square feet (500 series gas). Divide your seating area by the heater's coverage and round up.
Is one big heater or two small heaters better?
For most patios, two smaller heaters on opposite sides give more even warmth than one large heater on one side, because radiant heat is strongest directly in front of the heater.
How many heaters does a restaurant patio need?
Measure the seated area and divide by heater coverage, then add a little for wind. A 1,200 square foot patio typically needs six to eight heaters, ideally zoned on separate controls.
Does wind affect how many heaters I need?
Yes. In open, windy spots plan for more coverage or a larger model, even though radiant heat holds up better in wind than heat that warms the air.