What is the Ideal Room Size for a 1,500-Watt Space Heater?

When you get cold, there are quite a few ways to warm up quickly. There are few things that really matter, you can light a fire in the fireplace, brew hot cocoa, or even turn on the heater. But how do you know what heater size you need to provide warmth? 

Depending on which unit you choose and your specific circumstances, one heater might be more energy-efficient than another. This is one of the characteristics that you should find in a heater. But the question is, how much space do you need to heat? What kind of fuel will you use to power it? How much will it cost to operate? All of these factors need to be taken into consideration before you buy.

These small appliances are great for warming one or two rooms at a time. So if you’re planning on using yours as your home’s sole source of heat, keep reading this content for a piece of helpful info about choosing the best size for your needs and situation. 

How Much Space Can a 1500 W Heater Heat?

When you need to heat a small space, the last thing you want to think about is the heat output of the heater. You just want something that works efficiently and doesn’t cost too much to run. But it can be a bit tricky to know what those stats mean and how they impact your house heating experience.

Supplemental space heaters may save lives, but estimating how many watts you need may be challenging without blowing through your electricity bill. Remembering that 10 watts per square foot are required to heat a space, you can determine the number of watts you need.

A 500-watt bulb is suitable for a desk, cubicle, or bathroom. For a small office, a small bedroom, or a bathroom, a 750-watt bulb will work well. For smaller spaces such as bathrooms, offices, bedrooms, or bathrooms, a 1000-watt bulb will be sufficient. 

If you want to stay warm and cozy in a medium-sized room, office, kitchen, or modest-sized living room, use 1500 watts.

How to Cut Space Heater Costs?

Space heaters are a great way to keep your home warm when the temperatures dip. They’re also much cheaper to operate than your primary heating source, which will be welcome news if you’re on a tight budget this winter. However, operating costs may still be a little higher than you anticipated and may cost you a lot of money.

Having a space heater might seem like a terrific idea, but you might be anxious about how much it costs. If you buy a heater with a digital thermostat, you will see exactly how hot you will get before you turn it on, rather than turning the heater on full blast and dripping sweat 30 minutes after it is off.

You can also buy a heater with an “eco mode,” which reduces heat production once the thermostat setpoint has been reached. A good rule of thumb is to remember that 10 watts per square foot are needed. For example, if you have a 50-square-foot bathroom, 500 watts should keep you warm.

Heater Room Size by BTU

The size and construction of your home or building will play a significant role in determining how much heat you need from your heater. The best way to know what size space heater you need is by measuring the room’s dimensions, adding together all its indoor areas, and finding the total square footage.

You can use this BTU heater room size table to determine how much space a furnace will heat or to know what size furnace to purchase based on the size room. These probably answer most of your questions. Kerosene and home heater oil furnaces are just two of the many types of heaters rated in BTUs.

Heater Room Size BTU

Reference: https://www.pickhvac.com/space-heater/room-size/

A 1500-watt 5200 BTU room heater, for example, is effective enough to heat a 170-square-foot space. A one-ton 12,000 BTU heater, in comparison, can heat up to a width of 400 square feet.

Heater Room Size by Watts

The amount of power delivered by an appliance is measured in watts, which is the product of amperage and voltage. Electricity is the only power source for these heaters; a gas heater, for instance, would be a fan-operated radiator heater. You can rate electric heaters, radiator heaters, baseboard, and oil heaters in watts.

An oil-filled radiant-heat space heater, for example, might use oil instead of water to retain heat after the power has been turned off. The heat generated by an electric heater should be 10 watts per square foot. For a 150-square-foot room, you would need a heater with 1,500 watts of heating power.

This table may guide you:

Heater Room Size by Watt

Reference: https://www.pickhvac.com/space-heater/room-size/

Example: What size heater is required to heat 300 square feet?

In the Room Size Column, you will find that a 3000-watt heater is suitable for a 300-square-foot room if you want to heat a room of 300 square feet.

How Many Watts Per Square Foot?

According to standards, an electric heater must provide 10 watts of heating power per square foot to maintain indoor comfort and avoid any health problems. You should not heat a garage or other inadequately insulated or noninsulated spaces with an electric heater unless they meet this standard.

Factors Affecting Heater Room Size Calculator

You must have the best heater-sized calculator to achieve the desired goals. Without an effective tool, it will be challenging to get accurate results. The ease with which you can measure the area of a space and how efficient your room is at retaining heat varies widely depending on the factors involved.

The BTU and Watts Heater Room Size Tables just above show indoor spaces and don’t apply to unheated garages, outbuildings, tents, or RVs, for example. Other factors, such as the 5200 BTU heater room size, will affect the outcome.

Ceiling Height

If a room has ceilings higher than 8 feet, you may want to opt for a larger heater to ensure adequate heating. For example, a 6,000 BTU heater would be sufficient for a 200-square-foot room. If the ceilings are 10 feet high, select an 8,000 or 9,000 BTU model instead.

You can multiply the BTU by 1.25 to get the appropriate size. For example, the table states that 6,000 BTU is required. 6,000 x 1.25 = 7,560 or 8,000, for example. You can also do this with wattage. For example, 1,000 x 1.25 = 1,250 watts.

Heat Needed

If you live in a cold climate and want to maintain a comfortable level of temperature in your home, a heater with 10 watts of heating power per square foot should suffice. If it’s cold outside, you might need 15 watts per square foot instead. They based the Heater Room Size by BTU Table on an average of 30 BTUs of heating power per square foot. On a day when Missouri is experiencing sub-freezing temperatures, and you wish to keep your space heater on, you may need 40 BTUs per square foot. 

On the other hand, if you want to keep your space heater on a chilly day in Missouri, 20 BTUs per square foot should be sufficient.

Drafty Rooms

A 1500-watt heater will overheat a large room unless the windows are well sealed. But most manufacturers equip their heater units with advanced safety features to reduce the chance of fire and overheating. A poorly sealed window will admit air and make the room cold, even if the insulation is adequate. In this case, you must estimate the room size to be 100 square feet rather than 150 square feet, as listed in the Table.

The Difference Between Convection and Infrared Heater

Air convection heaters warm the air by blowing air heated by a heating element throughout the device. Objects and people can be warmed using infrared heaters emitting infrared radiation. When it is freezing in the shade on a cool spring day but warm in the sun, you are standing in the sun and suddenly feel cold; you are experiencing the type of heat the sun provides. Infrared heaters function the same way, utilizing infrared radiation absorbed by objects as they move through them. These devices can produce up to 1,500 watts, making them fairly safe.

How Much Electricity Does a 1500 Watt Space Heater Use?

In addition to wattage, kilowatt-hours, and billing rates, predicting the amount and price of a space heater over time is a complicated process. You should consider where you plan on using the heater (if it’s a tiny space, you may not want it on continuously) and how long you think it’ll be active.

A 1500-watt heater operates for one hour, heating a modest-sized room, consuming 1500 watts. Since household products use links substantial energy, heaters are relatively economical. A coffee maker can use anywhere from 600 to 1200 watts, and a waffle iron requires 800 to 1500 or more. 

Many refrigerators have similar energy costs per kilowatt-hour, which means other common products have similar energy costs.

Calculate How Much Will a 1500 Watt Heater Cost to Run

Planning when purchasing electronics or selecting an energy rate can be beneficial. If you want to use your heater all night to keep you warm, you might want to plan. To determine how much electricity you’ll need, multiply the wattage by the number of hours it will be in use. Divide this number by 1000. Your energy company might charge you $0.25 for electricity. We must therefore multiply the amount of electricity used by the cost of electricity to come up with a final figure.


To summarize, a central heating system can heat an area of 200-300 square feet. To heat even more space, you need to buy a heater with more wattage. Some heaters can heat an entire room and not just one area. Be sure to know what kind of heater you need to look for, the one that is just right for the area you want to heat up. Reading reviews and articles, and contacting a professional may be a big help.


How much does it cost to run a 1500-watt heater for 24 hours?

It costs about 12 cents per hour to run a 1500-watt heater for 24 hours. The average cost of electricity in the United States forms the basis for this. The cost of running a 1,500-watt electric space heater is; $0.20 per hour to run, or $4.80 for 24 hours (per day).

How big of a room will 1500 watts heat?

1500 watts will heat a room that is approximately 150 square feet.

How many feet does a 1500-watt heater cover?

A 1500-watt heater can cover up to 150 square feet.