Underfloor Heating with Carpets: Does It Work?

Underfloor heating is an increasingly popular heating solution for homes in the UK. It provides consistent and efficient heat distribution, frees up wall space, and eliminates the need for radiators or baseboard heaters. And it is especially lovely on your feet on those cold winter mornings.

However, one common question that arises is whether underfloor heating is compatible with carpets. Let’s explore the topic of underfloor heating with carpets, discussing the feasibility, benefits, considerations, and best practices for combining these elements in your home.

As a quick spoiler – yes, they are compatible. But you need to understand some key considerations before you choose your set-up.

Carpet & Underfloor Heating Compatibility

The compatibility of carpets with underfloor heating depends on various factors, including the type of carpet, its thermal resistance, and the type of underfloor heating system being used.

Carpet Type:

Some carpet types are more suitable for use with underfloor heating than others. Thin carpets with low thermal resistance allow for better heat transfer compared to thicker, more insulating carpets. Carpets with natural fibres, such as wool, tend to be more heat-conductive and allow heat to pass through effectively.

Thermal Resistance:

The thermal resistance of a carpet is measured in TOG (thermal overall grade) rating. It indicates how well a material can resist heat flow. For underfloor heating systems, it is recommended to choose carpets with a TOG rating of 1.5 or less to ensure efficient heat transfer.

Underlay:

The type of underlay used beneath the carpet can affect heat transfer too. Opt for underlays specifically designed for use with underfloor heating systems, as they are often thinner and have lower thermal resistance. These underlays allow heat to pass through more easily, maximising the warmth transferred through the carpet.

Heat Output:

Consider the heat output of the underfloor heating system. The temperature of the heating system may need to be adjusted to compensate for the insulating properties of the carpet. It is advisable to consult with a heating professional or the manufacturer of your underfloor heating system to set the optimal heat output needed.

Benefits of Underfloor Heating with Carpets

Comfort

The obvious one; underfloor heating provides radiant heat from the floor, creating a warm and comfortable feel on your feet throughout the room. When combined with carpets, the heat is evenly distributed, resulting in cosy and pleasant flooring that is gentle on bare feet.

Energy Efficiency

Underfloor heating can be more energy-efficient compared to traditional heating systems, as it operates at lower temperatures. Carpets act as an additional layer of insulation, helping to retain the heat and reducing heat loss, thus improving energy efficiency.

Design Flexibility

By having heating under your carpets, you get greater design flexibility with the room, as there will be no radiators or heating vents visible in the room. This provides more freedom in furniture placement and interior design choices, allowing you to go wild in your interior design ventures.

How Underfloor Heating Works

Before delving into the specifics of underfloor heating with carpets, let’s briefly understand how underfloor heating systems operate. There are two primary types of underfloor heating: electric and water-based (hydronic) systems.

Electric Underfloor Heating

Electric underfloor heating systems consist of heating cables or mats installed directly beneath the floor covering. These systems are typically powered by electricity and controlled using thermostats or programmable timers. The cables or mats heat up, warming the floor and radiating heat upwards to warm the room.

Water-based (Hydronic) Underfloor Heating:

Water-based underfloor heating systems involve a network of pipes installed beneath the floor. Warm water is circulated through these pipes, which heats up the floor and transfers heat to the room. The water is heated by a boiler or heat pump, and the system is controlled by a thermostat.

Considerations for Underfloor Heating with Carpets

While underfloor heating with carpets offers numerous benefits, there are several important considerations to keep in mind. Let’s explore these factors in more detail:

Carpet Type & Thickness
Thin, low tog-rated carpets are more suitable for use with underfloor heating as they allow better heat conductivity. Carpets with thicker piles or high tog ratings may impede heat transfer and reduce the efficacy of the heating system. It is recommended to choose carpets with a tog rating of 1.5 or lower for optimal performance.
Thermal Resistance
Carpets have a thermal resistance, often referred to as the R-value, which indicates their ability to resist heat transfer. To ensure efficient heat transfer, select carpets with low thermal resistance. Manufacturers or suppliers can provide information on the thermal resistance of different carpet options.
Carpet Underlay
The underlay beneath the carpet can also impact heat transfer. It is advisable to choose underlays with low thermal resistance to maximise the effectiveness of the underfloor heating system. Some underlays are specifically designed for use with underfloor heating and offer improved heat conductivity.
Heat Output & System Sizing
Your heating systems should be properly sized and designed to account for the additional thermal resistance of the carpets. It is important to work with a qualified heating engineer or underfloor heating specialist who can calculate the appropriate heat output and ensure the system can adequately heat the room.
Thermostat & Temperature Control
The thermostat for the underfloor heating system should be compatible with carpeted floors. Some thermostats have built-in floor sensors that measure the floor temperature accurately, regardless of the carpet thickness. It is important to consult with a heating specialist to select a suitable thermostat for your specific carpet and underfloor heating setup.

Best Practices for Underfloor Heating with Carpets

To ensure the successful integration of underfloor heating with carpets, follow these best practices:

Professional Installation: Underfloor heating systems should always be installed by a qualified professional who has experience working with carpets and understands the specific requirements for optimal performance.
Carpet Selection: When choosing carpets, consider the type, thickness, and thermal resistance. Opt for carpets with low tog ratings and consult with carpet manufacturers or suppliers for guidance on suitable options for underfloor heating.
Consult with a Heating Specialist: Consult with a heating specialist or underfloor heating expert to assess the compatibility of your chosen carpet and underfloor heating system. They can provide valuable insights, system sizing calculations, and recommendations for optimal performance.
Regular Maintenance: Proper maintenance of the underfloor heating system and carpets is crucial to ensure longevity and efficient operation. Follow the manufacturer’s guidelines for maintenance, and schedule regular inspections to identify any potential issues or necessary adjustments.

In Summary

Underfloor heating with carpets is indeed feasible, provided that the appropriate considerations and best practices are followed. With a careful selection of the carpet and a professional installation, you can enjoy the benefits of a heated carpet system.