Published specifications
| | Output | Fuel | Body | Mobility |
|---|
| Mr. Heater MH125 | 125,000 BTU | Propane, forced air | Not published | Portable |
| Dura Heat LPC80 | 50,000–80,000 BTU, adjustable | Propane, convection | Not published | Portable |
| GasOne | 50,000 BTU | Propane | Stainless steel | Wheels |
| EAST OAK pyramid | 48,000 BTU | Propane | Stainless, glass tube | Not published |
| Amazon Basics | 46,000 BTU | Propane | Not published | Wheels, water-fillable base |
| Dr. Infrared DR-239 | 3,000 W | Electric infrared | IP55 rated | Wall or ceiling mounted |
Two of those rows are not terrace heaters and are here deliberately. The forced-air MH125 and the convection LPC80 are shop and tent equipment: they warm the volume of an enclosed or semi-enclosed space rather than radiating at seated guests, which makes them right for a marquee, a delivery bay or a back-of-house area and wrong for a dining table.
How many heaters, and where
The rule of thumb that works in practice: one freestanding mushroom or pyramid heater covers a group of roughly four to six seats, placed so the reflector is above head height and the seats are within about a 6 to 8-foot radius. Radiant heat drops off sharply with distance, so eight heaters spread thin across a terrace warm nobody, while the same eight placed one per table group warm everybody.
Three placement rules that matter more on a commercial terrace than at home. Keep heaters out of service lanes — a heater on a route staff walk twenty times an hour will get knocked, and a knocked gas heater is a serious event. Keep them clear of awnings, umbrellas, planting and anything overhead, to the clearance the manual specifies. And on a windy or exposed terrace, prefer the water-fillable base: the Amazon Basics publishes that feature and it is a meaningful stability improvement on a tall, top-heavy unit.
Cylinder logistics is the actual job
- Count cylinders, not heaters. A 50,000 BTU burner run flat out empties a 20-pound cylinder in roughly eight to nine hours of burn. Eight heaters on a busy winter weekend is a real pallet of gas, and you need full and empty storage that is outdoors, upright, secured and clear of exits.
- Decide who swaps and when. A cylinder change by an untrained member of staff at 10pm in the rain is where incidents happen. Train specific people, keep a leak-test spray or soapy water at the station, and do changes before service rather than during it.
- Talk to your fire officer and your insurer first. Quantities of LPG stored on commercial premises are regulated, and requirements differ by jurisdiction and by whether the terrace is covered. Ask before you buy, not after the first inspection.
- Buy spares as part of the order.Not just cylinders — regulators, hoses and igniters are the parts that fail, and being one heater down is much better than being one heater down and waiting a week for a hose.
- Never run a gas heater in an enclosed space. A terrace with the sides dropped, a fully sealed marquee or a tented smoking area is not outdoors in the sense a manual means. The CPSC recommends CO alarms on every level of a building and outside sleeping areas, and an enclosed guest space with combustion appliances in it needs that thinking applied properly.
When electric is the better commercial answer
Mounted electric infrared removes almost everything in the section above. There are no cylinders to store, buy, swap, secure or account for; nothing standing in a service lane; nothing to knock over; and nothing to relight when the wind gusts. For a covered terrace with power available, a row of mounted units is usually the better operational decision even though the energy costs more per hour.
The DR-239 publishes 3,000 watts and an IP55 weather rating, and mounts to a wall or ceiling. Check the supply requirement before ordering at volume — 3,000 watts per unit across a terrace is a real electrical load and wants an electrician’s input on circuits and distribution, not a string of extension leads. Our patio heaters for covered porches page covers mounting height and angle, and propane vs electric patio heaters runs the running-cost comparison properly.
Where real commercial equipment is sold
If your terrace is permanent and sizeable, the retail route above may be the wrong one, and it is worth saying so plainly. Hospitality suppliers and hearth contractors specify hard-plumbed natural gas heaters — no cylinders at all, far lower running cost, and nothing for staff to handle — and overhead electric radiant arrays wired into the building’s supply. Both need a gas fitter or an electrician, both usually need permits, and neither publishes a retail price we can verify, so we name the channel rather than quoting figures.
What to ask a supplier for, with a terrace plan in hand: output per unit and the coverage radius they will commit to, mounting or plumbing requirements, the IP or weather rating, replacement part availability and lead time, and whether the quote includes commissioning. The last one is the item that moves a quote most.
One commercial detail that applies whichever route you take, and that the FTC’s own shopping guidance supports: order on exact manufacturer and model number rather than on a description or a photograph. At volume, a near-identical lookalike at a slightly lower price usually differs in the body material or the burner, and a terrace with two different heaters on it needs two sets of spare parts.
