Basement floors can be downright cold. As a do-it-yourselfer, you may have attempted to warm the area with space heaters or other forms of temporary heat without much success. Whether you have a full basement, partial basement, or daylight basement, the solution to your problem may be radiant floor heating.
How Does Radiant Floor Heating Work In a Basement?
Radiant floor heating works by installing tubing under a floor, or in this case, concrete. These tubes are filled with warm water and this water is circulated throughout the floor.
This heat radiates upward, warming the concrete, floor covering, and the surrounding air. Known as hydronic radiant heating, this design employs special tubing, called PEX. The design allows for the tubing to be looped across a large area, like a basement pad.
Generally speaking, radiant heat in a basement can raise the temperature up to ten degrees per hour. Since a basement is protected from the elements, a hydronic system is a very efficient choice for heat. Concrete tends to hold temperature better than wood, so radiant heating is a great choice, especially if the concrete is thick. Additionally, the basement is within the insulation of the home, so retaining heat is much easier than say, a garage floor.
Are Heated Basement Floors Safe For My Family?
Yes. Radiant floor heating is safe to use, even in areas where ventilation is less than perfect. Since the heat source is isolated under concrete, it can never become hot enough to become dangerous and does not produce any dangerous fumes.
Do Heated Basement Floors Heat the Whole House?
Yes. Since heat rises, there is no better place to install radiant heating than a basement. Plus, the heat can be concentrated in cooler areas, such as within 8’ of an exterior wall. It can also be reduced, for example, in a storage room with no occupants.
What Are the Pros and Cons of Radiant Floor Heating in a Basement?
- Radiant floor heating is excellent for heating a space with concrete floors, like a basement.
- A radiant heat system in a basement takes advantage of how heat rises. In contrast to forced air systems, radiant floor heating in a basement will work passively to warm the first floor without fans, nor noise.
- Finishing a basement would usually require upgrading the home’s heat pump or furnace to heat the space. Radiant floor heating in a basement not only allows for separate control of the temperature in the space, but may eliminate the need for a costly HVAC upgrade.
- Basements can be musty. Radiant floor heating evaporates excess moisture in the basement, helping to reduce mold and mildew.
- Pouring new concrete in an existing basement is more difficult than pouring a regular pad, making it more expensive for the same amount of concrete.
- Hydronic radiant heating becomes more economical as the project becomes larger. The rule of thumb suggests that if the basement is less than one fifth of the total square footage of the home, installing a hydronic system may not be economically feasible.
Are Heated Garage Floors a Fire Hazard?
No. Radiant floor heating is completely safe if installed properly. Manufacturer’s instructions should always be followed to ensure the system is completely sealed and grounded.
How to Install a Heated Basement Floor
Installing radiant floor heating in a basement is usually done as part of a remodeling project. Since a hydronic system employs both plumbing and electrical systems, it is recommended to hire professionals to make the final connections when the project reaches that point. The manufacturer of your system will also provide detailed instructions for matching the appropriate tubing to the size of the pad.
Hydronic Radiant Heat Installation
Because a hydronic system uses both electricity and water, you will want to orient the system to adjoin the garage, or some other space to house the components. This system uses a device called a manifold, which works like the spokes of a wheel to distribute water wherever it is needed. This allows for greater control of the system after installation. Other components include a boiler and circulation pump.
Here is a list of tools you may need:
- Concrete tools, such as a mixing paddle, drill, and trowel
- Utility knife
- Wood and/or masonry chisel
- PEX expander tool
- PEX tubing cutter
- Tape and/or adhesive
- Electrical tools, such as a wire stripper and crimper, screwdriver, and multimeter
Step 1. Layout
Measure the entire basement floor area. If you have a partial basement that does not mirror the first floor, measure each section and add them together. This number will be asked of you anytime you are shopping for materials, so keep it handy.
Hydronic systems have the huge advantage of being customizable, so a detailed plan will make the project much easier and useful. Getting help from the manufacturer during this phase is strongly recommended, as time and money-saving options may be available.
Professionals will design the system to have more tubing near doors and windows if you have a daylight basement. This is done because up to 20% of the heat lost will escape through an exterior wall. This is not usually necessary in full basements as they are below grade, however, you can also adjust the heat using the adjustments on the manifold.
Pro Tip. If you have extra tubing left on a roll, add another zone to the system instead of tossing it. You can always just turn that zone off if it is not needed.
Step 2. Install the Insulation, Vapor Barrier, and Tubing Guides
Hydronic system installations are essentially two systems, however, manufacturers today have improved the installation process by combining components and reducing the complexity. For example, a vapor barrier between the ground and the concrete is required by code.
This is because groundwater levels rise and fall naturally, so if the level gets too close to the surface, it can pull the heat from the system into the ground. The vapor barrier blocks any moisture transfer between the tubing and the ground, ensuring that the heat will always radiate upwards.
Most hydronic installations will use pre-formed panels. These panels are insulated on one side, have a vapor barrier built-in, and provide a mechanical connection to the tubing. To install these panels, start at the corner of the basement where the connections to electricity and water will be located.
Align the first full panel with an adjoining wall and snap another panel to it. These panels connect with interlocking edges and eliminate the need for additional reinforcement by using the weight of the concrete to keep them in place.
After reaching the opposite wall, cut the next panel in half and begin the next row. This method prevents any two panels from sharing a joint and will retard future cracking of the concrete. Continue until the entire area is covered with the panels.
Pro Tip. Cover the entire area with the panels even if there will be no tubing on a few. This will not only save concrete but will also make finishing the pad much easier and uniform.
Step 3. Install the Tubing
Start the tubing from one end of the first panel, making sure to leave enough extra to make the connections to the manifold. Simply wind the tubing around the supports in the panel and secure them using a PEX strap.
Once the end of the pad is reached, the tubing must be sleeved through a small section of conduit that will extend from the concrete. This will protect the tubing as it exits the pad and prevent damage as it expands and contracts.
Step 4 . Make the Connections
With both the tubing and electrical runs made, you can connect the system together. Connect the tubing to the manifold and the manifold to the boiler and pump using PEX connectors on both ends.
The electrical connections can use either 110v or 220v service, depending on the system requirements. Ensure you have space and service requirements available before beginning the project to avoid any unpleasant surprises. If you are inexperienced working with electricity, hiring a professional to make these connections is recommended.
Pro Tip. You may be tempted to use the same mechanical push-on PEX connectors often used in residential plumbing. Do not use these, as these types of connectors must remain accessible and using them will cause a code inspection to fail.
How Warm Should a Heated Basement Floor Be?
Probably the biggest advantage of a heated basement floor is the controllability of the heat. The manifold function within the system allows one section of the floor to be warmer than another.
Zones can be created just like with your security system so that areas with little or no traffic can be adjusted as needed. Especially in a basement, a hydronic system will be very efficient to use as the heat does not escape as it would, for example, in a garage.
How Much Does a Heated Garage Floor Cost?
The cost for a basement floor heating system will vary from region to region, but expect to pay between $8.00-$20.00 USD per square foot. Hydronic heating in a basement is controlled by a thermostat, so the operating cost is usually just a few dollars per day.
Heated floors in a basement are very cost-effective to operate, but the system itself can be expensive. If you plan to live in the home for many years, or live in a climate where heated floors are standard, the return on investment is usually good.
How Long Do Heated Floors Last In a Basement?
The mechanical parts, such as the pump and boiler, will typically have a finite lifespan of about 15-20 years. The tubing, however, will typically last 20-30 years. This is double the average lifespan of a similar forced-air system, such as a heat pump or furnace. The system is designed to be left on all the time, relying on a thermostat to regulate the temperature.
Is Heating My Basement a Good Idea?
Radiant floor heating has many applications but works no better or more efficiently than in a basement floor. Hydronic heating in a basement is nearly maintenance-free, very durable, and essentially silent. If you want your basement to be comfortable, inviting, and just a great place to spend time, radiant floor heating may be the best investment you can make.