How Much Clearance Does a Patio Heater Need Under an Awning?
Quick answer
A freestanding propane patio heater needs 2 to 3 ft between the top of its reflector and any combustible material above it, and 2 to 3 ft at the sides, according to four full-size heater manuals checked; where a manual contradicts itself, use 3 ft in both directions. A wall or ceiling-mount gas infrared heater such as the Bromic Tungsten needs 3 ft above and at the sides (14 in above with its heat shield) and must be mounted at least 8 ft off the floor. Electric infrared heaters need about 3 ft clear in front, 6 to 13 in to the ceiling, and a mounting height of 6 to 8 ft. Gas heaters are only allowed under an overhead cover with no more than two walls, or with a set share of the walls left open.
A freestanding propane patio heater needs 2 to 3 feet between the top of its reflector and anything combustible overhead, which includes awning fabric, and 2 to 3 feet at the sides. That is the range in the four full-size propane heater manuals checked for this page (a tabletop model asks for 18 inches above), and two of them give different numbers in different sections of the same booklet, so the safe reading is 3 feet above and 3 feet around. Wall and ceiling-mount heaters work on different numbers: a Bromic Tungsten gas heater wants 3 feet above it and to the sides and must hang at least 8 feet off the floor, while electric infrared heaters need about 3 feet clear in front and can sit as close as 6 inches to the surface they hang from.
The figures circulating online (18 inches, 24 inches, 36 inches, 47 inches, 6 feet, 8 feet) all appear in real heater manuals. They conflict because they belong to different heater types, and several are the heater's height above the floor, not the gap to the awning.
Clearances by heater type, from the manuals
Figures are as printed in each maker's US instructions. "Above" is measured from the top of the heater; "floor" is the heater's minimum height above the ground.
| Heater and manual | Above (to combustibles) | Sides | Front, floor and other |
|---|---|---|---|
| Freestanding propane: Hiland HSS-A | 2 ft in the safety section; 36 in in the pre-lighting checklist | 3 ft in the safety section; 24 in in the checklist | Checklist: "Heater is outdoors (outside any enclosure)" |
| Freestanding propane: Hiland HLDS01 | 2 ft (24 in) | 3 ft (36 in) | Same figures in both sections; checklist says outside any enclosure |
| Freestanding propane: Mi-T-M propane patio heater (MH-0042 manual) | 3 ft in the safety section; 2.3 ft in the checklist | 2 ft in the safety section; 3.3 ft in the checklist | 47 in (1.2 m) to the top and sides if walled on all sides with no roof; allows partial enclosures (below) |
| Freestanding propane: Well Traveled Living patio heater | 36 in | 36 in | Checklist says outdoors, outside any enclosure |
| Tabletop propane: Fire Sense items 60262, 61322, 62969 | 18 in | 24 in | Outdoor use only, outside any enclosure |
| Wall or ceiling-mount gas infrared: Bromic Tungsten Smart-Heat Gas 300 and 500 (US) | 3 ft; 14 in with the Tungsten heat shield | 3 ft | At least 8 ft above the floor; allows partial enclosures (below) |
| Electric infrared: Bromic Tungsten Smart-Heat Electric (US) | On suspension tubes, face at least 250 mm (about 10 in) from the ceiling for 2000 W and 3000 W, 330 mm (about 13 in) for 4000 W and 6000 W | Keep combustibles away from sides and rear | 3 ft (900 mm) in front; floor at least 96 in (8 ft) ceiling-mounted, 71 in wall-mounted, 8 ft for Canadian approval; 20 in between heaters |
| Electric infrared: Infratech W-series | 6 in from the ceiling | 18 in from adjacent walls | 3 ft in front; floor at least 6 ft if UL listed (Infratech's reference manual suggests 7 ft), 8 ft if UL/cUL listed; heaters 3 ft apart |
Two patterns stand out. Every mounted heater, gas or electric, carries a floor height, and those floor heights (6 ft, 71 in, 8 ft) are the source of most "6 feet" and "8 feet" claims you will read. And no manual in this set mentions awnings by name: each speaks of combustible materials, overhead structures or ceilings, and a fabric awning is a combustible overhead material in every case.
When a manual contradicts itself
Two of the five propane manuals print different clearances in different places. The Hiland HSS-A safety section says "three (3) feet from the sides & two (2) feet from the top." Its checklist before lighting says the heater must be "at least 36" on top and at least 24" on sides." The Mi-T-M manual does the reverse: three feet on top and two at the sides in the safety section, then "2.3 feet on top and at least 3.3 feet on sides" in its checklist.
The practical fix is to take the larger number in each direction. For the Hiland HSS-A that is 36 inches above and 3 feet at the sides; for the Mi-T-M, 3 feet above and 3.3 feet at the sides. Across all four full-size propane manuals, 3 feet above and 3 feet (or 3.3 feet for the Mi-T-M) at the sides satisfies every figure printed.
Read your own manual: clearances sit in the general safety section near the front and again in the checklist before lighting. Check both. If your model gives a larger number than this page, the manual wins.
The partial enclosure rule: may a gas heater run under an awning at all?
Before distances, a gas heater has to be allowed under the awning in the first place. An awning with the patio walls around it is, in the manuals' language, a partial enclosure. Two manuals in this set spell out which partial enclosures they accept.
The Mi-T-M propane manual says the heater "may be installed with shelter no more inclusive than":
- Walls on all sides but no overhead cover, keeping 47 in (1.2 m) from combustibles at the top and sides.
- "A partial enclosure which includes an overhead cover and no more than two side walls. These side walls may be parallel, as in a breezeway, or at right angles to each other."
- An overhead cover and three side walls, "as long as 30 percent or more of the horizontal periphery of the enclosure is permanently open."
The Bromic Tungsten gas manual uses a similar list: an enclosure with walls on all sides and at least one permanent opening at ground level; a partial enclosure with an overhead cover and no more than two walls; or an overhead cover with more than two walls, where at least 25% of the total wall area is completely open and at least 30% of the remaining wall area is open and unrestricted.
Under a patio awning, the house wall counts as one wall. A privacy screen on one side makes two, which both manuals accept. Side curtains on both ends make three walls plus a roof, and the open-area percentages decide. Close a front drop shade as well and a gas heater is no longer permitted by either manual.
The other three propane manuals give no partial enclosure allowance at all. Their checklists before lighting say the heater is "outdoors (outside any enclosure)," the same words Mi-T-M uses, but with no list of acceptable shelters behind them. Nothing in those manuals authorizes running the heater under an overhead cover, so if yours reads that way, keep the heater in the open.
Electric heaters have no combustion gas and no enclosure rule of this kind, which is the main reason they are the usual choice for covered patios.
Fabric awnings: where to measure and what to choose
A retractable or fixed fabric awning is combustible overhead material, so every overhead figure in the table applies to it in full. Treated fabric does not change that. Fabric certified to NFPA 701 is tested for how it spreads flame, not for how it handles hours of radiant heat from below; the guide to awning codes and fire ratings explains the difference, and the awning fabric guide covers how acrylic, polyester and vinyl differ.
Measure to the lowest point of the fabric above the heater, not to the brackets. A retractable awning slopes down from the wall, so the fabric is lowest at the front bar and the valance. The projection and pitch guide shows the arithmetic: a 10 ft awning at 14 degrees drops about 29 inches from bracket to front bar.
Worked example
Say a freestanding propane heater stands 7 ft 6 in to the top of its reflector. Using 3 ft above, the fabric directly over it must be at least 10 ft 6 in off the patio.
An awning whose front bar sits at 84 in (7 ft), a common target in the awning mounting height guide, cannot have that heater anywhere under it. Even near the wall, brackets at 9 ft 5 in leave the fabric about a foot too low.
The heater has to stand outside the awning's footprint, with 3 ft between the edge of its reflector and the front bar or valance. That puts it in the open, which is also where the stricter manuals want it.
That is why electric suits a fabric awning better. A wall-mounted electric infrared heater sits below the awning brackets, needs 3 ft clear in front, and faces down and out rather than up. Bromic's manual says to make sure the heater "is not facing the ceiling or flammable or combustible substances/materials," so aim it at the seating area, angled down, and check the distance from its face to the fabric above.
Heaters that clip onto an awning's front bar or arms put heat directly against the frame and fabric, and only the awning maker can say whether its frame and cover accept them. Unapproved add-ons are a common warranty exclusion; see awning warranties.
Metal covers and patio roofs
Aluminum or steel panels are not combustible, but wood beams, rafters, fascia boards and polycarbonate glazing are, and the overhead figures apply to them. Ceiling fans and lights sit in the heat plume. And the partial enclosure rule applies to a gas heater under any roof, metal or not, because it is about ventilation rather than fire.
The differences between these covers are set out in metal and polycarbonate awnings. If year-round heat is the goal, a roofed structure with a flat ceiling is the setting the Bromic and Infratech ceiling-mount instructions describe; awning vs patio cover compares the two.
Where this answer stops applying
- Other models. These manuals cover the main heater types, not every model sold. Clearances vary even within one brand, as the Bromic gas and electric manuals show.
- Heat shields and deflector kits change the figures. Bromic's Tungsten heat shield (part 2620165 or 2620166) cuts the overhead clearance from 3 ft to 14 in. A kit only changes the numbers if the heater's own manual says so; a generic deflector on a propane heater does not license a smaller gap.
- Restaurants and commercial patios. Fire codes and fire marshals can restrict propane heaters under commercial canopies, near exits and in enclosures beyond what these manuals say. See restaurant awnings for heaters, side panels and permits.
- Grills. Cooking appliances have their own manuals and, for apartments, a fire code distance; see can you grill under an awning.
- Fire pits. Gas fire tables ask for 72 to 96 in overhead and wood-burning pits for no overhead at all; see can you put a fire pit under an awning.
- Weather. Bromic's gas manual says not to install the heater "in open locations subject to rain," and its electric manual recommends mounting under cover where possible. All five propane manuals list wind below 10 mph in their checklist before lighting.
Frequently asked questions
How far should a patio heater be from an awning?
For a freestanding propane heater, 2 to 3 ft from the fabric above the reflector and 2 to 3 ft from the sides, depending on the manual; use 3 ft both ways if your manual gives two sets of figures. For a Bromic Tungsten gas heater, 3 ft above and to the sides. For electric infrared, keep 3 ft clear in front of the heater and do not point it at the fabric.
Is the "6 feet" or "8 feet" rule right?
Those figures are minimum mounting heights above the floor for wall and ceiling heaters: Infratech's UL listing allows 6 ft, its cUL listing 8 ft, Bromic's electric heater 71 in on a wall and 96 in on a ceiling, and Bromic's gas heater 8 ft. They are not the distance between a heater and an awning.
Sources and further reading
- Bromic Heating: Tungsten Smart-Heat Gas instruction manual, US, V2.3 (installation requirements and clearances)
- Bromic Heating: Tungsten Smart-Heat Electric instruction manual, US, V1.8
- Infratech: W-series installation and operating instructions
- Infratech: Reference manual (mounting options)
- AZ Patio Heaters (Hiland): HSS-A patio heater owner's manual
- AZ Patio Heaters (Hiland): HLDS01 patio heater owner's manual
- Mi-T-M: Propane patio heater operator's manual, MH-0042-PM11
- Well Traveled Living: Patio heater assembly, care and use instructions
- Fire Sense (Well Traveled Living): Outdoor tabletop heater, items 60262, 61322, 62969
How we write our guides: figures are typical US ranges checked against manufacturer documentation, published standards and installer pricing. Read our editorial standards. Spotted an error or outdated detail? Request a correction.