Different heater styles and models may have different spacing requirements. For example, some heaters run hotter than others and may need extra clearance. That’s why it is critical to follow the instructions for your heater model. That said, there are some general guidelines for positioning standard electric baseboard heaters, as well as some basic safety precautions. The common exception to this guideline is thick carpeting. If the carpet pile is tall enough that it might cover the air opening, the heater should be installed above the carpet. Another exception is with baseboard heaters that must have an imposed space added between the heater and the floor.
Baseboard Heater Maximum Height
One valid criticism of baseboard heaters is that they take up wall space and limit the placement of furniture. With that in mind, is it possible to mount a baseboard heater high—even up near the ceiling—and preserve some of that wall space? Heater manufacturers typically do not specify a maximum installation height, but there is a reason why these are called baseboard heaters: Most standard heaters provide the best performance when they are placed close to the floor. This is because hot air rises and cold air drops. Baseboard heaters heat the air above them, not below.
Space in Front of Baseboard Heaters
Baseboard heaters typically need at least 12 inches of space in front of the heater. You can place a couch or chair in front of a heater, but it must be at least a foot away. Placing furniture closer than that creates a potential fire hazard, and it can greatly diminish the heater’s performance by restricting airflow to and from the heater. Note that this minimum applies to standard electric baseboard heaters. Heaters with fans need much more clearance—typically 3 feet or more. When installing a baseboard heater near a door, make sure the heater cannot be blocked by the door when it is fully open. A door that comes within 12 inches in front of a heater is a fire hazard, just like furniture that is too close to a heater.
Baseboard Heater Side Clearance
Drapes, furniture, and other combustible materials should be at least 6 inches away from each side of a baseboard heater. As noted, most baseboard heaters are designed so that their ends can touch baseboard wall trim, but this applies only to the very ends of the heater unit. Anything placed to the side of the heater, or above and to the side, should be at least 6 inches away. Because it is difficult to situate baseboard heaters safely with drapes, it is usually best to install the heater elsewhere when possible. Since baseboard heaters are highly effective under windows, another alternative is to install window blinds that stop at sill height when closed.
Baseboard Heaters and Electrical Outlets
Electrical codes typically do not prohibit installing heaters below wall outlets, but most heater manufacturers recommend against it. Faceplates and outlet bodies are heat resistant. Yet the concern is that a cord plugged into the outlet will drape down onto the heater. This could melt the cord’s plastic insulation, creating a serious shock and fire hazard. The safest approach is to avoid installing heaters under outlets altogether. The National Electrical Code (NEC) requires a wall outlet every 12 feet along walls. If an outlet is required where you’d like to install a heater, you may be allowed to use a heater with an integrated electrical outlet to meet the NEC outlet requirement. One alternative is to install two shorter baseboard heaters to work around an existing outlet. For example, instead of installing a single 96-inch-long baseboard heater, you may decide to install two 48-inch-long heaters on either side of the outlet. Many electric baseboard heaters can be ganged, or wired in parallel, both on the same circuit breaker and both on the same thermostat. Check heater instructions and your local codes for safety requirements.
Position of the Baseboard Heater
The baseboard heater should be installed in a horizontal position, within 1/4-inch of level. Use a bubble level on top of the heater casing to determine level. The heater should never be mounted vertically or upside-down.
