Updated November 2, 2026.

Start with the occupied area

Plan outdoor heating around the places where people sit rather than the entire property boundary. Draw the table, chairs, doorways and usual walking routes. Add the heater position only after marking those features. A heater that blocks access is a poor fit even when its advertised coverage sounds sufficient.

Coverage depends on the heater design and installation, as well as the surrounding conditions. Bromic notes that model, mounting height and wind affect gas-heater coverage. Treat a coverage diagram as model-specific guidance rather than a promise that every square foot in a rectangle will feel the same.

The manual decides clearances

Read the exact model’s installation instructions before purchase. Required distances to ceilings, walls and combustible materials vary. Do not copy a clearance number from a different heater, and do not assume that a patio umbrella or fabric canopy is compatible with the proposed location.

For fixed gas or electrical work, use the installer and approvals required for that equipment and location. A shopping guide cannot establish that a particular circuit, gas supply or enclosed area is suitable. Resolve those questions before choosing hardware or drilling mounting points.

Choose a layout that stays usable

For a portable model, account for its whole base and the space people need to pass it. For a mounted model, consider the intended heat direction and the seated positions. Move the drawing through a normal evening: chairs pulled out, guests arriving and the door opening.

Keep the manufacturer’s clearance zones clear during use, not only at installation. A storage basket, cushion or moved chair can change the arrangement. Do not move a hot or operating portable heater unless its instructions explicitly permit the action.

Do not solve wind with unsafe enclosure

If wind makes the seating area unsuitable, reconsider the location or whether to heat it at all. Do not surround an outdoor combustion heater with improvised sheeting or operate it indoors to improve performance. Outdoor-only equipment must stay within its approved use and ventilation conditions.

The same care applies to temporary entertaining arrangements. A covered party area can differ from the open patio where the heater normally stands. Recheck the actual surroundings rather than assuming an outdoor label makes every roofed space acceptable.

A pre-purchase worksheet

Record the seating-area dimensions, the proposed heater location, overhead materials, available utilities and the exact manufacturer’s clearances. Ask a qualified installer to review any fixed installation. If the diagram does not work, choose a different layout or equipment instead of shrinking the required spacing.

Should you size by BTU alone? No; output, direction, installation and conditions all matter. Can one heater serve every corner of a large patio? Do not assume it can. Size the occupied zones and follow the maker’s planning information for each proposed unit.

Sources and further reading