Underfloor Heating

What is Underfloor Heating?

Underfloor heating, also known as UFH, is an innovative heating process in the residential construction industry. The use of underfloor heating systems has been around for centuries when it was first engineered by the Romans to heat their marble floors. The process is currently enjoying a resurgence in popularity as an alternative heating option. Energy-efficient as well as being a space saver, underfloor heating is a viable solution to traditional alternatives by providing warmth and comfort to your home from the ground up. On the flip side, underfloor heating may not be the best option for all homes. Use the following information to help determine if underfloor heating will accommodate the heating requirements for your home.

Types of Underfloor Heating

Homeowners can choose between two of the most common underfloor heating systems. The first of the radiant systems is the hydronic, or wet, system. The benefit of the wet system is its use of warm water generated by the central heating system that may include a boiler or water heater. As the water runs through plastic pipes installed between the sub floor and the finished floor, it heats the surface to a comfortable temperature between 73 degrees and 89 degrees. An added benefit of the wet system is its use of water at low temperatures resulting in cost effective water heating.

The second underfloor heating option is the electric mat system. With this type, cables are attached to either a mesh mat or to a continuous roll of material. The mats or rolls are connected to the power supply and thermostat. Installing an electric system versus a wet system may be cheaper but in the long run the electric system is more expensive due to the increase in your monthly energy bill.

Cost of Underfloor Heating

The cost of installing either the water-based or electric system varies and depends on whether, you hire a licensed contractor, plumber, and electrician. All of these services are required depending on the system you choose. Besides having the knowledge and certification to install the system, each expert will also know how to calculate to allow for room size, ceiling height, type of flooring to be installed, anticipated temperature for each room, and what to expect in realistic terms of heat loss based on all of these factors.

With an electric system, if your home is being built or remodeled and the sub-flooring and finished flooring has not yet been installed, this will help lower the cost as it eliminates the need to pay to have the flooring removed prior to installation.

You’ll also need to factor in the cost of materials which will include underfloor heating mats or cables, insulation for the system to lay on, heating sensors and/or thermostats, and fees for a licensed electrician.

A water-based system, while cost effective over time, will initially cost more than an electric system to install. If your home is in the process of being constructed or renovated, it’s much easier and cheaper to install a water-based system and to address any initial issues, one being enough room between the sub-floor and the finished floor to install the pipes. If there isn’t enough room, which may be encountered in older homes, adjustments will need to be made to accommodate the pipes. This can add to the cost factor of a water-based underfloor system.

Keep in mind, with an electric system, a contractor is working with thin wiring that’s easy to manipulate. With the water-based system, pipes are much thicker and there must be enough room to work with for installation.

Pros of Underfloor Heating

One of the main pros of underfloor heating is that it’s out of view and doesn’t need a designated area of floor space for storage. Other advantages include:

  • All types of underfloor systems evenly distribute heat to the rest of the room.
  • Wet underfloor heating systems can warm a large area more efficiently than traditional heating systems or electric underfloor systems.
  • An advantage of underfloor heating systems is the way it warms the initial area by conducting the heat through the floor surface versus using a forced-air heating system.
  • An underfloor water heating system is cost effective once installed and is best suited to new construction so the floor can be designed from the start to accommodate the pipework.
  • A water system requires less energy resulting in the lowering of the monthly energy bill.
  • An electric underfloor system works best in smaller areas.
  • For allergy sufferers, underfloor heating is the perfect option since the process does not push allergens, dust, or pet dander into the air like an air-forced system.
  • The use of a programmable timer with an electric flooring system allows you to warm specific floor areas versus the entire home. The underfloor system is designed to work separately from your central heating system.

Cons of Underfloor Heating

Underfloor heating installation can be costly and is a better option for new homes being built, a new room addition, or for homes being remodeled or renovated which includes removal of the finished floor. This is especially true of the water-based system because of the complex process of installing the pipes and/or expanding the area between the sub-floor and finished floor. It can also be more expensive if the flooring is being installed on the second floor of a 2-story home.

Because underfloor heating works with lower temperatures, whether installing the water, gas, solar, or electric system, it can take longer to warm individual rooms.

There may be restrictions as to what type of furniture can, and cannot, be placed on the flooring. Electric underfloor heating is not recommended for floors covered in thick carpet.

An electric underfloor heating system has the additional cost of hiring certified electrician to ensure all of the wiring to the cables and thermostat are correctly connected.

underfloor heating

Choosing the Right Underfloor Heating System

Whether you choose electric or water underfloor heating, there are several things to keep in mind when choosing the system that best suits your home’s needs.

With electric underfloor heating, depending on room size and shape, you have the choice of installing heating mats which are good for large areas. If choosing wiring versus mats, this option has the flexibility to fit into small or tight areas as well as under a variety of floor types other than carpets. An electric underfloor heating system can be more expensive to operate for large areas and is better suited and more economical when used in a smaller area such as a bathroom, kitchen, or dining room. If using electric underfloor heating, adequate insulation is a major factor to help prevent heat loss.

Water underfloor heating incorporates the use of networked pipes to pump hot water throughout the flooring system. It is more expensive to install than an electric system but requires less energy, keeping monthly costs low.

Life Span of Underfloor Heating

  • The lifespan is over 25 years for an electric underfloor heating system as long as the flooring remains intact.
  • A system using a gas boiler lasts approximately 10 years due to the many components that may need to be replaced.
  • Water-based systems are designed to last for 50 years.
  • It is recommended to purchase an extended warranty from a reputable company to cover parts, pipes, cables, and thermostats that may need replacing due to accidental damage or a faulty part.

Flooring Considerations

If you are considering underfloor heating but not sure if the type of flooring you are having installed is suitable, consider these helpful tips.

  • Carpeting over underfloor heating systems is possible as long as the thermal resistance (tog) of the carpet and underlay is less than 2.5.
  • Many homeowners enjoy the beauty and easy maintenance of terracotta, stone, slate, porcelain, and ceramic tile. Each type is suitable for underfloor systems because of their thermal conductivity, although if using thick tiles, it will take more time to thoroughly reach peak temperature. Once it does, heat distribution is the same as with thin tiles.
  • Laminate, vinyl, and timber/hardwood flooring is possible but each type must be certified for UFH use. Not all brands are compatible with underfloor heating systems.

Underfloor Heating Maintenance

For the most part, your new underfloor heating system will not require a lot of maintenance. An annual maintenance check will address replacement of any parts causing leaks due to faulty seals or washers. A check-up will also ensure valves are functioning properly.

A water-based system shouldn’t need any pipe maintenance but in the event there is a problem, having the pipes flushed by a professional can remove any build-up or blockage.

Overall, depending on your choice of system, additional components that need periodic and/or annual maintenance include circulating pumps, boilers, central heating systems, heat pumps, solar panels, and radiators.

Hiring a Licensed Contractor

Choose a reputable contractor who is licensed, bonded, and insured to install the underfloor system. Contact several companies to provide estimates, go over their contracts, and provide information regarding their warranty for material and labor. Also, as an added checkpoint, contact your local Better Business Bureau to see if there are any current or past complaints filed for the contractors you are considering.

Underfloor heating has several advantages as well as disadvantages. Ask questions and be thoroughly informed whether the time, cost, and overall efficiency of this type of flooring is the best option for your new home, room addition, or for a remodeling or renovation project.

Share this article