How do I know what size electric baseboard heater I need?

Choosing the right size electric baseboard heater for your room is important for comfort and efficiency. An undersized heater will not provide enough warmth, while an oversized unit is inefficient and can make the room uncomfortably hot. Follow these steps to determine the proper heater size for each room.

Calculate the Room’s Square Footage

The first step is to measure the room’s dimensions to determine its square footage. Make sure to multiply length x width to get the total square footage. Here is an example:

Room dimensions: 15 ft long x 12 ft wide = 180 sq ft

Be sure to measure all livable square footage, including closets and other usable areas. Round up to the nearest 10 for an approximate value if needed.

Determine the Room’s Heat Loss

Next, you’ll need to calculate the room’s heat loss, measured in BTUs per hour. The heat loss depends on the climate, insulation, and other factors. Here is a rough estimate:

• Well-insulated room: Assume 20 BTUs per square foot
• Average insulation: Assume 25 BTUs per square foot
• Poor insulation: Assume 30 BTUs per square foot

Multiply the square footage by the BTU per square foot factor based on your room’s insulation. Using the example above:

180 sq ft x 25 BTUs per sq ft = 4,500 BTUs per hour heat loss

Select a Baseboard Heater Size

Now that you know the room’s heat loss, you can select an appropriately sized electric baseboard heater. Choose a heater that matches your room’s heat loss as closely as possible. Common sizes include:

• 1,000 watts = 3,413 BTUs per hour output
• 1,500 watts = 5,119 BTUs per hour output
• 2,000 watts = 6,826 BTUs per hour output

For the example room with a 4,500 BTU per hour heat loss, a 1,500 watt (5,119 BTU) heater would be ideal. The closest size should provide sufficient heating power for the space.

Adjust for Local Conditions

You may need to adjust up or down one heater size depending on the climate and room specifics:

• Increase for cold climates or poorly insulated rooms
• Decrease for moderate climates or well-insulated rooms
• Increase for rooms with many windows or exterior walls
• Decrease for interior rooms with no outside walls

It’s better to err on the side of a slightly oversized heater rather than undersized. A larger unit can always run at lower heat settings.

Space Heaters Evenly

Make sure to space baseboard heaters evenly around the perimeter of the room. Long runs over 10 feet may require multiple heaters. Place heaters under windows where most heat loss occurs.

Gaps between heaters should not exceed 15 feet. Use wire or metal covers between heaters for a seamless look.

Compare Installation Costs

When selecting heaters, consider the installation cost for electrical work. More powerful 240-volt heaters require special wiring, while 120-volt heaters can use normal outlets. Here is a comparison:

Heater Type	Voltage	Power Output	Installation Cost
120 volt	120V	up to 1,500W	Low – uses normal outlets
240 volt	240V	2,000 – 5,000W	High – requires special wiring

240V heaters provide more power, but may not be cost effective unless electrical upgrades are needed anyway. Check with an electrician on installation costs for your specific situation.

Select a Thermostat

Electric baseboard heaters require a thermostat for temperature control. Choose an adjustable thermostat that mounts to the wall at a convenient height. Models with a built-in thermometer and digital display make it easy to set your desired temperature.

For the best comfort and efficiency, install a programmable thermostat. These allow you to set customized heating schedules for different times of day. Programmable thermostats can cut heating costs by 10-30% per year.

Consider a Whole-House Solution

If heating many rooms in your home, consider installing electric baseboards throughout for a whole-house heating system. This provides consistent temperatures and comfort in all living spaces.

With a whole-house design, you can also install a central programmable thermostat to control all heaters simultaneously. This makes scheduling and temperature adjustments much easier compared to individual thermostats.

Hire a Professional Electrician

Always have a licensed electrician install your new electric baseboard heaters. They will ensure proper wiring, circuit capacity, and compliance with local building codes. This guarantees safe and efficient operation of your new heating system.

Discuss your rooms’ heating needs with the electrician to select the ideal heater sizes. They can also advise you on thermostats and other controls to complete your system.

Conclusion

Choosing the proper electric baseboard heater size comes down to calculating your room’s heat loss and matching it to an appropriate heater output. Consider local climate, insulation, windows, and other factors when sizing heaters. And always have a professional electrician install the system for safety and efficiency.

With correctly sized and installed electric baseboards plus a programmable thermostat, you can enjoy consistent, comfortable heat throughout your home.

Frequently Asked Questions

How is heat loss calculated for a room?

Heat loss is calculated based on the room’s square footage and insulation factor. Multiply the square footage by an insulation factor like 20 BTUs per sq ft for well insulated rooms or 30 BTUs per sq ft for poorly insulated rooms. This gives you the room’s hourly heat loss in BTUs.

Should I size a heater to exactly match the heat loss?

It’s best to match the heat loss calculation as closely as possible by choosing the electric baseboard heater output in BTUs that fits your room’s needs. Having a slightly oversized heater is better than undersized.

How much space should be between baseboard heaters?

Evenly space heaters around the room perimeter, with gaps no larger than 15 feet between heaters. Long wall runs over 10 feet may require installing multiple heaters for even coverage.

Should I hire an electrician to install heaters?

Always hire a licensed electrician to install and wire your new electric baseboards. They will ensure proper circuit capacity, electrical connections, and building code compliance for safe operation.

What size breaker is needed for a 240V baseboard heater?

A 240V circuit with a 30 amp breaker can support a single 3,600 watt or two 1,800 watt heaters. For larger loads over 4,800 watts, a 50 amp breaker is typically required. Have your electrician size the breaker for your heaters’ total wattage.

How accurate are the BTU ratings for electric heaters?

Most baseboard heaters have a heat output tolerance of +5% to -10%. So actual output may be slightly higher or lower than the rated BTUs. Size your heater based on the nominal BTU rating during sizing calculations.

Should I get a programmable thermostat?

Definitely consider installing a programmable thermostat to control your electric baseboard heaters. Programmable thermostats optimize heating efficiency by customizing temperatures for different times of day. They can reduce annual heating costs by 10-30%.

Installing Electric Baseboard Heaters: Step-by-Step

Once you’ve selected the properly sized heaters, the next step is professional installation for safe and seamless operation. Follow these steps:

Step 1: Turn Off Power

The electrician will first shut off power at the main circuit breaker panel before doing any work. This prevents accidental shocks or shorts during the installation.

Step 2: Inspect and Prepare the Wall

Walls should be cleared of any furniture or décor where heaters will be positioned. Use a stud finder to mark stud locations for secure mounting. Clean the wall surface so heaters will adhere properly.

Step 3: Install Mounting Brackets

Attach sturdy metal mounting brackets at desired heights for each baseboard heater using screws anchored into the wall studs. Brackets hold the weight of the heaters.

Step 4: Wire the Heaters

The electrician will connect wires from the main circuit panel to each baseboard heater location per local electrical code. This may require installing new wiring if upgrading to 240V heaters.

Step 5: Mount the Heaters

Lift each baseboard heater into place and attach securely to the wall brackets using screws, clamps, or fasteners on the back of the unit. Ensure heaters are oriented properly.

Step 6: Install Thermostat

Mount the programmable thermostat to the wall per included instructions. Connect control wires from the thermostat to each baseboard heater to enable temperature control.

Step 7: Confirm Proper Operation

Turn the power back on and test each heater to confirm proper operation and heating. Set the thermostat to call for heat and ensure the heaters respond appropriately.

Step 8: Finish Installation

Snap any cover plates or trim pieces into place for a seamless look. Use foil tape to cover gaps between heaters. Confirm the room warms to the desired temperature and make any adjustments needed.

That covers the complete installation process. Following proper protocol and having a professional electrician handle the wiring ensures your new electric baseboard heating system will work safely, efficiently, and reliably.

Maintenance Tips for Electric Baseboard Heaters

Performing simple maintenance on your electric baseboard heaters prevents issues and keeps them working optimally. Follow these tips:

• Clean dust/debris – Use a soft brush attachment on a vacuum to remove any dust or dirt buildup inside the heater enclosure or around heating elements.
• Check for damage – Look for signs of dents, cracks, or damage to the heater covers or internal components. Replace if necessary.
• Inspect wiring – Check for fraying or damage to any power cables or connections. Contact an electrician immediately if any wiring issues are found.
• Test heating function – Turn on heaters occasionally during off seasons to verify proper operation.
• Change filters – For models with air filters, replace them according to manufacturer specifications, generally every 1-3 months.
• Update caulking – Reapply caulk/insulation around heater enclosures as needed to prevent air leaks.

Following these simple maintenance steps will extend the service life of your electric baseboard heaters and keep them performing as intended.

Conclusion

Determining the right electric baseboard heater size for a room involves calculating the square footage and heat loss BTUs to select a heater output that matches closely. Consider insulation, climate, and other factors as well in the sizing calculation. Professional installation is highly recommended to ensure proper electrical connections, building code compliance, and safe operation. With regular maintenance, quality electric baseboard heating provides an effective whole-home heating solution.