Eric the Heater Guy
The honest answer: it depends on your layout, ceiling height, wind, and fuel. Here's how the count is actually figured — then we'll do the real math for your patio, free.
Ten inputs. Get these right and the heater count falls out of the manufacturer's specs — get them wrong and no formula saves you.
Heat the seats, not the square footage. Two patios with identical floor area can need very different counts depending on where people actually sit.
Length, width, and shape set the coverage zones. Long narrow patios size differently than square ones — the geometry matters more than the total square feet.
Wall/ceiling infrared, freestanding mushroom, glass-tube tower, and enclosed-burner units all cover space differently. The model is half the answer.
Higher mountings spread heat wider but weaker — which changes both the model and the count. This is the input most people forget.
Every model publishes minimum distances to ceilings, walls, and overhangs. Clearances can rule a model out before the count is even calculated.
The biggest variable on an open patio. Wind steals heat and kills open flames — exposed spaces need more heat per seat, closer spacing, or wind-rated models.
Natural gas suits permanent wall/ceiling installs; propane suits portable and rental setups; electric infrared shines under covered patios. Fuel constrains the model choices.
Portable units flex with the layout and the season; mounted units disappear into the architecture but need structure, fuel lines, and permits. Different math, different count.
Each model publishes a coverage figure at a given mounting height. The real count is coverage zones laid over your seating plan — not square footage divided by a magic number.
What the fire marshal allows, what the structure supports, and what the gas or electrical scope costs can all change the plan. See commercial patio heating requirements.
Starting points — not a substitute for sizing to your actual patio.
In calm, covered areas. Drop to ~8 ft where wind hits. Higher mountings cover wider but weaker — model and count both change.
In calm conditions. Wind is the enemy of portable heat — exposed patios need more units, closer to seating.
Mark where guests sit first, then lay coverage zones over those seats. Empty walkways and host stands don't need heat.
Heating the whole patio evenly is rarely the goal. Zone heaters over seating banks so dead areas don't drive the equipment count.
How the thinking actually goes. Your patio will differ — that's the point.
The setup: narrow sidewalk-adjacent patio, 8–10 tables, a 9-ft storefront overhang, natural gas available.
What matters: mounting height under the overhang, clearance to the storefront, and seating rows — not the walkway down the middle.
The takeaway: wall-mounted infrared along the storefront often covers this footprint with fewer units than freestanding heaters — but only the overhang height and the model's published clearances decide which model.
The setup: 800 sq ft, 30+ seats, 10–12 ft ceiling, gas stubbed to the patio.
What matters: ceiling height spreads each heater's coverage wider but weaker; wind at the open sides; heaters zoned over seating banks rather than spread evenly.
The takeaway: the count doesn't scale linearly with square footage — higher mounting changes the model choice, and open sides may need tighter spacing than the middle.
The setup: no cover, real wind exposure, no gas line yet, lounge seating.
What matters: wind is the dominant variable; there are no mounting surfaces; fuel logistics (propane storage and swaps) are part of the plan, not an afterthought.
The takeaway: open rooftops need more heat per seat than any covered space. Freestanding propane or wind-rated units, placed close to seating — and the propane plan gets figured out before the heater count is final.
The setup: coastal or canyon-adjacent exposure, regular gusts, existing open-flame heaters that keep blowing out.
What matters: open flames struggle in wind regardless of quantity; enclosed-burner models rated for wind; closer spacing; windbreaks change the math.
The takeaway: in wind, the model matters more than the count — the wrong heater underperforms at any quantity. Fix the model first, then size the number.
The setup: solid roof, 8–10 ft ceiling, existing electrical, dining tables.
What matters: electric infrared under a ceiling is efficient and clean; the manufacturer's ceiling clearances for the exact model; panel capacity for the load.
The takeaway: covered with a ceiling often points to electric — simpler install, no combustion or ventilation questions — but an electrician confirms the circuit capacity before anything is ordered.
I'll help you figure out the setup — heater count, models, and placement, sized to your patio. Free, no obligation.
You don't need to know the heater model. That's our job. The more of this you can send, the tighter the plan:
As a rule of thumb, 10–12 feet apart in calm, covered areas — closer (8 feet) in wind-exposed spots. Exact spacing comes from the manufacturer's published specs for the model and mounting height.
Roughly one per 100–150 square feet in calm conditions — more in wind. Layout matters more than square footage: heaters should cover seating, not empty floor.
Yes. Higher mountings spread heat wider but weaker — which changes both the model and the count. That's why we ask for ceiling height on every quote.
No — and anyone selling you one is guessing. The count comes from the manufacturer's published specs applied to your layout: dimensions, ceiling height, wind exposure, fuel, and seating. That's what the free Patio Heating Plan does.
A photo of the space and rough dimensions are enough to start. Seating count, ceiling or mounting height, fuel type, and your city help too — but you don't need to know the heater model. That's our job.
That's the free Patio Heating Plan — send patio photos and dimensions and we'll spec the heater count, models, and placement.
Eric the Heater Guy