Skip to Content

Is It Bad to Put a Furnace in Your Crawl Space?

Is It Bad to Put a Furnace in Your Crawl Space?

Share this post:

This post may contain affiliate links. If you click an affiliate link and make a purchase, I may earn a commission. Also, as an Amazon Associate I earn from qualifying purchases.

If you decided to explore your home and found an unfinished area under your house, you’ve probably come across a crawl space. These areas resemble basements but have vents that let external air in. The greatest benefit to these spaces is that you can install piping systems there.

Since this area is somewhat big and can accommodate multiple devices, some consider installing furnaces there. However, is it bad to put a furnace in the crawl space?

If you’re careful, it can be a great idea to install a furnace in a crawl space. The area can hide the furnace from view and can make the upper floors warm. However, there can be some hazard risks that you need to be mindful of.

Continue reading if you want to learn more about installing furnaces in crawl spaces. Let’s get started!

Can You Put a Heater in a Crawl Space?

You can surely install a heater in your crawl space, depending on the dimensions and layout of your home. Crawl spaces are excellent places to conceal the furnace and keep it out of view because they’re under the house to hide away the plumbing systems and such.

If you meet all the requirements, you won’t encounter any significant issues. You just need to make sure there’s enough space available and that you set everything properly.

There might be some benefits to placing a heater in a crawl space. For instance, the majority of heating system problems happen on winter days. This is because your heater is operating the most during that time.

Yet, if you set it in a crawl space, the underground space will shield your furnace from climate problems and keep it in good condition.

What Kind of Furnace Do I Need for the Crawl Space?

Furnaces come in a wide variety of types. Some, however, may not be suitable for the crawl space.

Vertical radiators, for example, won’t function well because of the crawl space’s low ceiling.

Fortunately, there are some options to think about. If you want to install a heating system, you have two choices. You can install a heater or a furnace. Here are the types of furnaces that you can install:

Convection Electric Heaters

A convection heater is a type of radiator that warms and circulates air using convection currents.

This kind of furnace won’t cost you much money to run because it doesn’t consume much electricity in the crawl space. The standard convection heater consumes around 1500 watts of power per hour, which doesn’t cost a lot.

Additionally, you won’t require as much heat if you insulate the crawl space before installing the furnace. This can enable you to further reduce the heating bill even more.

Horizontal-Flow Furnaces

A horizontal flow furnace is a path through which warm air exits the radiator and into your ductwork so that it spreads around the house.

One benefit of these furnaces is that you can turn them on their side, allowing them to flow the air on one side and discharge it out the other.

Given that the space is constrained by the low ceiling, this heater is ideal for crawl spaces.

It’s important to know that they have a fixed flow direction, so you can’t adjust it to your liking.

Factors to Consider When Placing a Heater in a Crawl Space

While installing furnaces in a crawl space may be a good idea in some situations, there are several factors to take into consideration.

Generally, the installation of a heater in a crawl space isn’t prohibited by the regulations. However, there are still a few significant factors that may cause you to reconsider.

1 – Moisture

Your crawl space is most likely humid and dim. They typically become wet during the warm, humid summertime when there’s a lot of moisture.

Mold may grow as a result of moisture condensing on surfaces and other components. Because it prefers moist, humid environments, mold will proliferate quickly.

Therefore, there’s a risk that installing a heater will both facilitate mold growth and make the mold spores easier to flow through the furnace.

2 – Cost

Crawl spaces frequently lack sufficient insulation. Due to this problem, your home loses a considerable amount of heat.

Although it’s not strictly essential, insulation in the crawl space lowers heating costs. People can sometimes keep their heaters on for a long time since winter can be extremely cold.

If you leave the heater running for a long time, you may pay extra for your electricity bills as it uses a lot of electricity. Therefore, you should keep the costs in mind when installing a furnace.

3 – Accessibility

As mentioned before, the crawl space is often a hidden section of the house. The majority of the time, a hatch allows for internal access to this space. Because of the tight space and entry point, this can make access to this area difficult.

Hence, installing the system and fixing it afterward can be quite challenging due to the limited accessibility.

What You Need to Prepare to Install a Furnace

You must ensure that the crawl space is secure before you install the heater. To create a safe space, you must consider the following points.

1 – Ventilation

Ventilation is one of the most crucial factors you should consider. If the system is functioning properly, the surface will be capable of circulating air, preventing moisture buildup. Therefore, it won’t lead to mildew, mold, and wood rot growth.

So, if you don’t have vents built, you must constantly create an air draft. Establish at least two crawl space vents on opposing sides of the home to provide proper airflow. The ducts should be at least an inch above the floor level.

Make sure to place them around the sides of the residence and on the backside.

If you can’t install vents, you can use a fan blower heater. These heaters function by blowing air over a source of heat. Therefore, as it encourages both heating and ventilation, it might be a terrific addition to your crawl space.

2 – Fire Prevention

It goes without saying that furnaces pose a fire hazard. They have the potential to start a fire if positioned too close to flammable objects.

What’s more, the low ceiling of your crawl area makes it always flammable, especially if it’s uninsulated. Thus, you should exercise caution to avoid any fire by doing the following:

Place a Thermometer

You may want to place a wireless temperature probe in the crawl space close to the heater. These gadgets enable you to observe the temperature without being bound to the furnace.

Typically, they include another remote thermometer that shows the temperature of the crawl space from a distance. This way, you can conveniently measure the crawl space’s temperature on a regular basis and take quick action if it starts to get too warm.

Check for Any Leaks

Pipes from the plumbing system typically fill the crawl space. Additionally, the area runs electrical wiring throughout the entire house.

Due to the electrical wiring and the heater, any pipe leaks can be dangerous and start a fire.

If you spot a leak, get in touch with a specialist right at once to have it repaired. Also, remove anything that can readily catch fire, such as a paint bucket or old clothing.

Lower the Amount of Plugged Cords

Since there are many electrical devices present, the number of cords hooked into a single outlet should be kept to a minimum.

A single socket can quickly overload due to the high current that the devices take from it. This can result in a full-blown circuit breaker, increasing the risk of electrocution and starting a fire.

Hence, never connect more than two devices into the same socket at once. Use only outlets that support several plugs if you want to connect many electronics at the same time.

3 – Flood Prevention

Make sure to take the appropriate flood prevention precautions if you reside in an area with a high risk of flooding. The ideal crawl space height is between 44 and 48 inches since it allows for better access and prevents major flooding.

Additionally, the crawl space needs to have enough outlets to let flood water enter and exit the crawl chamber. Examine the grade of the terrain around your property, in addition to your gutters to make sure they’re in working order.

You should also have a reliable drainage system. Crawl spaces might benefit greatly from a French drain. With the help of these outlets, you can transport any excess water that accumulates in your crawl space elsewhere.

These drains are especially beneficial if the water forms into puddles. The drains stop surface and groundwater from infiltrating and ruining your crawl area.

The installation of an automated sump pump is another option. It’s a system that recognizes rising water flow and levels in an area. Using this device, the water won’t be able to rise past a certain height if you install it correctly.

Final Thoughts

Crawl spaces can house furnaces easily. The area may shield the heaters from weather-related issues, such as rain. With proper caution, these furnaces will install easily without causing you any hassles.

However, there are some factors that you need to consider and prepare for before you set up the furnace. For example, you need good fire prevention measures to safeguard the area. Additionally, make sure that there’s enough accessibility so you can do maintenance easily.

This way, you’ll have a safe crawl space and a furnace that will last for a long time.


If you want more backyard tips including recipes, how-tos and more, make sure you subscribe to my youtube channel

Share this post: