Concrete Floor Radiant Heating: Types, Benefits and Installation Tips

Are you tired of cold, uncomfortable floors during the winter months?

Look no further than a concrete floor radiant heating system!

In this article, we will explore the numerous benefits of this innovative heating technology, including its energy efficiency, comfort, and even heat distribution. We will also discuss the different types of radiant heating systems available, basic installation tips, and how to select the best flooring for your new system.

Whether you're planning a new construction project or upgrading your existing heating system, concrete floor radiant heating is a game-changer that will transform the way you experience winter. So, let's dive in and discover all the advantages of this revolutionary heating system.

Concrete floor radiant heating: Things to consider

• Types
• Benefits
• Drawbacks
• Installation tips
• Is thin-slab better?
• Best flooring type
• FAQ

Types and differences

There are two main types of concrete floor radiant heating systems: electric and hydronic.

Electric radiant heating systems consist of electric heating cables or mats that are installed directly onto the concrete slab or in between layers of flooring. Electric radiant systems are typically easier and less expensive to install, but they can be more expensive to operate over time. When used with a thicker concrete floor, the floor will store the heat longer and make your house comfortable for hours without further electrical input.

Hydronic radiant heating systems use a network of plastic tubing to circulate hot water or other heating fluid through the concrete slab. These are known as "wet installations." The water is heated by a boiler, which can be powered by electricity, gas, or oil. Hydronic systems are more complex to install and require more space for piping and heating equipment, but they are generally more energy-efficient and can be more cost-effective in the long run.

The tubing is embedded in the concrete during construction or placed on top of the slab before the flooring is installed. Hydronic radiant systems are typically more expensive to install, but they can be more energy-efficient and cost-effective to operate over time.

Both electric and hydronic radiant heating systems can be controlled with a thermostat, allowing you to adjust the temperature according to your preferences. They can also be used in conjunction with other heating systems, such as a furnace or heat pump, to provide supplemental heat as needed.

Concrete floor radiant heating systems can also be divided into systems that use a large thermal mass of a concrete slab floor and those with a lightweight slab over a wooden subfloor.

Due to the high heat capacity, the thick concrete slab system is perfect for storing the heat from solar heating systems, which have fluctuating heat output. However, the disadvantage of thick concrete floor radiant heating systems is their slow thermal response time.

Benefits

Concrete floor radiant heating systems offer a host of benefits that make them an excellent option for residential homes.

1. Energy Efficiency: Radiant floor heating is more energy efficient than traditional heating systems because it heats the room from the ground up. This means that the heat is distributed more evenly and effectively throughout the space, reducing the amount of energy required to maintain a comfortable temperature.
2. Comfort: Radiant heating provides a more comfortable heating experience compared to traditional heating systems. The heat is distributed evenly, eliminating hot and cold spots.
3. Improved air quality: Radiant heating systems differ from forced-air heating systems in that they do not spread dust, allergens, and other pollutants throughout the home. This can improve indoor air quality and reduce respiratory problems.
4. Space-saving: Radiant heating eliminates the need for bulky radiators or vents, freeing up valuable space in your home. This can be particularly beneficial in smaller spaces.
5. Durability: Concrete is a durable and long-lasting material, which means that a concrete floor with embedded heating elements or PEX tubes can last for many years with proper maintenance.
6. Increased home value: Radiant floor heating is considered a desirable feature among homebuyers, which can increase the resale value of a home.
7. Aesthetics: Radiant heating eliminates the need for unsightly radiators or vents, which can improve the overall aesthetics of your space.

Concrete radiant heating is an excellent option as the main heating system; it is the cheapest, saves energy, and it provides healthier and comfortable living. It is a perfect solution for residential homes.

Radiant heat in concrete slabs is retained, so when the  doors or large windows are open, it will not affect the temperature inside your home as much as with the forced air heating systems. A concrete floor with a high density (high R-value) insulation placed below the slab makes the floor one big radiator.

Drawbacks and limitations

While concrete floor radiant heating systems offer numerous benefits, there are also some drawbacks and limitations that should be considered before making a decision to install one.

• Upfront costs: The initial installation costs of a concrete floor radiant heating system can be higher than traditional heating systems, particularly if retrofitting is required.
• Inconsistent heating: The heating system may not provide consistent heat distribution throughout the space, particularly if the tubing is not spaced correctly or if the heat source is not properly sized for the space.
• Slow response time: These systems can have a slower response time compared to forced-air heating systems, which means they may take longer to reach the desired temperature.
• Flooring limitations: Certain types of flooring, such as thick carpeting or hardwood, may not be suitable for use with a concrete floor radiant heating system.
• Limited zoning: Radiant heating systems are not as easily zoned as forced-air heating systems, which can limit the ability to control temperature in different areas of the home.

Concrete floor radiant heating - Basic installation tips

The installation of concrete floor heating can be more complex than traditional heating systems, and if you have some experience, skills, knowledge, and the right tools, it is not necessarily hard to install. The process involves installing a network of pipes or electric heating cables beneath the concrete floor, which can be time-consuming and may require some construction work.

The best time to install concrete floor heating (also known as the slab-on-grade installation) is when installing a concrete slab. It is also important to make sure that the concrete floor is properly insulated to prevent heat loss and optimize the system's energy efficiency.

Here is the video example: How to Install Radiant Floor Heat Tubing in a Slab On Grade.

If you are already paying for the installation of the slab, the recommendation is to install the floor heating as well since the only additional cost is adding affordable PEX tubing, plus labor, of course.

In this case, when installing concrete floor heating for the whole house, there will be no need to buy pipes or heaters that will take up valuable home space.

PEX tubing is the best option for installation, and once it's installed inside the concrete slab, it has to be protected against damage and must allow for the free transport of hot water.

During the installation of concrete floor radiant heating, the reinforcement wire mesh should be properly positioned in the slab area before pouring the concrete. A polyethylene vapor barrier and insulation are also needed for efficient heat distribution. PEX tubing is then attached either with wire ties or special clips, and it is important to follow the manufacturer's instructions to secure the tubing.

PEX tubing is looped inside the concrete floor, and the spacing between the loops determines the amount of heat produced. The recommendation is to keep the loops one foot apart to make bending easier and ensure unobstructed hot water flow. The depth at which the PEX tubing is placed within the concrete slab will determine the temperature of the hot water used and how long it takes to heat the floor. The recommended concrete slab thickness is between 4 and 6 inches.

The most efficient and safe installation location is in the middle of the concrete slab, without any joints. It is recommended to use the entire length of the tubing to avoid potential leakage where joints are present. A new floor radiant heating system should be checked for defects before pouring the concrete by using air pressure of 50 psi, and the tubing must maintain the pressure for 24 hours without leaking.

Is installing a thin-slab floor radiant heating system better?

The thin-slab concrete floor radiant heating system is a better option than the previous one.

Thin-slab floor radiant heating systems are typically installed on top of an existing floor or subfloor. A thin layer of concrete is poured over the PEX tubing on the wooden flooring, allowing retrofitting over an existing concrete floor without significantly raising the floor height.

The heating elements can be embedded within a thin layer of concrete, gypsum, or other material, which provides a stable and durable foundation for the system.

As in the previous example, the PEX tubing is secured to the wood subflooring, not to the reinforcing wire. The height of the thin slab of concrete is usually 1.5 inches or 38 mm, so the tubing must be installed tightly to the floor to prevent protrusion through the concrete.

What is the best flooring for concrete floor radiant heating?

The best flooring for concrete floor radiant heating systems depends on several factors, including the type of heating system, the size and location of the space, and personal preferences for aesthetics and durability. Here are some flooring options that are compatible with concrete floor radiant heating:

• Tile: Ceramic or porcelain tile is a popular choice for covering a radiant floor heating system because it conducts heat well, is water-resistant, and is durable. It's important to choose a tile with low thermal resistance to ensure efficient heat transfer.
• Natural stone: Like ceramic tile, natural stone is a good conductor of heat and can be used with radiant floor heating. Stone floors offer a natural, rustic look and are resistant to scratches and stains. Additionally, tile and stone can be more difficult to install than other flooring types, which can increase the overall cost of the flooring.
• Engineered wood: Unlike solid hardwood, engineered wood is less susceptible to warping or shrinking due to changes in temperature and humidity. It can be installed over the heating system and comes in a variety of colors and styles.
• Luxury Vinyl Tile (LVT): LVT is a popular choice for covering a radiant floor heating system because it's durable, waterproof, and has a low thermal resistance. Additionally, although LVT is designed to mimic the look of other flooring types, some users may not find it as convincing as the real thing.

Installing the insulation under the subflooring can control the efficiency of radiant heating. The recommendation is to buy and install the insulation with an R-value greater than the R-value of the floor covering, so heat can go up, not below.

It's important to note that some flooring materials, such as carpet and solid hardwood, may not be suitable for use with concrete floor radiant heating as they can insulate the heat and reduce the system's efficiency. It is recommended to work with a licensed professional to ensure proper installation and compatibility with your specific radiant floor heating system.

Conclusion

Concrete floor radiant heating systems offer a cost-effective, energy-efficient, and comfortable heating solution for residential homes. While the installation process may require some construction work, it is a worthwhile investment for long-term benefits. It is important to work with a licensed professional to ensure proper installation, maintenance, and compatibility with the flooring material. With proper installation and maintenance, concrete floor radiant heating systems can provide a comfortable and cozy living space for years to come.

FAQ

Can radiant floor heating be used for cooling?

Yes, radiant floor heating systems can also be used for cooling. This is known as radiant cooling or radiant heating and cooling. The system works by circulating cool water or a refrigerant through the tubing or pipes installed beneath the floor surface, which absorbs the heat from the room and transfers it to the cool water or refrigerant. The cooled water or refrigerant is then circulated back to the cooling system to be re-cooled, and the cycle continues. However, it's worth noting that radiant cooling may not be as effective as traditional air conditioning systems in areas with high humidity levels.

Is radiant floor heating enough to heat the house?

Whether radiant floor heating is enough depends on various factors such as the size of the space, insulation, climate, and personal preferences. In general, radiant floor heating provides consistent and comfortable heat throughout the room, but it may not be enough in extremely cold climates without additional heating sources or if the space is not well insulated. It's essential to work with a licensed professional to ensure the proper sizing and installation of your radiant floor heating system to meet your heating needs.

Does radiant floor heating have to be in concrete?

No, radiant floor heating does not have to be in concrete. While concrete is a common material used for installing radiant floor heating, there are other options available such as thin-slab systems and systems installed under a finished flooring surface. In fact, some systems use electrical wires or mats to provide radiant heat, which can be installed under a variety of flooring types. The type of system and installation method used may vary depending on factors such as the size and layout of the space, the type of flooring, and personal preferences.