Guide to Underfloor Heating Heat Output

It’s essential to know the heat output of an underfloor heating system if you want your home to be heated evenly to a comfortable temperature. After all, the role of an underfloor heating system is to ensure that every room in your house is heated to a temperature you desire. You wouldn’t like to install a heating system only to have it underperform. You can only estimate how much heat you will require to keep your space heated if you first determine the heat loss. You should go for a system with a heating output that compensates for the heat loss.

Read on to know everything you should understand about an underfloor heating system’s heat output. You shouldn’t hesitate to contact us if you have any questions.

Floor Size

The heat output corresponds to the size of the heated floor area. If the heated area is extensive, the maximum heat output of your underfloor heating system will be higher. However, the heat output will depend on the size of the heated floor area compared to the overall room size. Large rooms have higher heat loss than smaller ones. If the heated area is less than 80% of the overall room size, the underfloor heating system might not produce enough heat to warm up the room. However, if your home is perfectly insulated, the heat from the system will be enough.

Floor Temperature & Floor Type

The heat output will also depend on the floor temperature. You will have a higher heat output if the floor temperature is high. It’s important to note that different floor types have different features. While some floor types can be heated to high temperatures, others can’t. How much you can increase the floor temperature depends on your floor finish. If your floor is made from dense and solid materials like stone and tile, there will be an efficient heat transfer from the heating element to the floor surface due to the good thermal conductivity of the flooring materials. For a higher heat output, stone and tile flooring can be heated up to 29°C degrees or higher. For soft flooring materials like wood, linoleum, or laminate, the situation is different. These materials have poor conductivity and can only be heated up to 27°C degrees. What happens if your flooring finish can only allow a floor temperature of 27°C degrees, yet you can’t achieve maximum heat output with this floor temperature? In this case, you should consider changing the flooring material to ensure the underfloor heating system will produce enough heat to work as your sole heat source.

Choose the Right Thermostat and Air Temperature

Many homeowners invest in advanced thermostats that control temperature based on the air or floor temperature. While measuring temperature, the thermostat relies on an air or floor probe. The thermostat and probe’s accuracy will significantly impact the heat output as the thermostat switches the heat on and off. You will need a much higher heat output to reach a higher room temperature. You will particularly need a higher heat output in the bathrooms where you need a higher air temperature of around 23°C, unlike other rooms that need a temperature of 21°C. Poor thermostat control or placing the thermostat probes incorrectly could result in under or overheating your rooms. Poor controls and poor placement of thermostat probes could also damage the floor finish. It’s advisable to invest in a quality thermostat that won’t compromise your flooring. When you invest in a quality thermostat, you are assured of quality temperature control and significant energy savings.

Floor Insulation Increases Heat Output

Floor insulation will also have a significant impact on the heat output. You can increase the heat output by using the proper insulation. The insulation can be placed right below the heating units or pipes. The insulation can also be placed below the medium or the screed on which the heating system is embedded. When there is no insulation, the heat produced by the underfloor heating system moves upwards and downwards. The heat might even escape to the ground below the structure, consequently wasting energy and money. Insulation boards come in different designs and thickness to provide the desired insulation. Insulation is the perfect way to achieve a lower heat output requirement and reduce heat loss if you can’t change the size of the heated floor area or the floor finish. You can keep the heat in by adding a cavity wall or additional floor insulation. You can’t go wrong with insulation if you seek to lower the heat output requirement of your heating system.

Underfloor Heating System Power

The ideal power of an underfloor heating system should be between 14-20W/m² to give the desired output, provided you have a reasonably warm home, and your floor is well insulated. The power output of an underfloor heating system is expressed in Watts per square foot. You should go for a 15-20W/ft² heating system to reduce the heat up time since the system will not be turned on throughout. If you only put the heating system on for half the time a room is in use, the power provided is equivalent to half the system’s Wattage.  A 20W/ft² system will yield a power output of 8-12W/ft² per hour.

Bathrooms and Other Rooms with Permanent Fixtures

The heat output will vary depending on the fixtures in a room. Certain rooms like the bathroom have permanent fixtures like toilets, baths, and the sink. You should not install an underfloor heating system beneath these fixtures. This means that you can only heat certain portions of your bathroom floor, leaving the areas where fixtures sit, and this will affect the heat output. When installing the heating system, you should never cut or shorten the heating cables. Avoid leaving any excess cable exposed or coiled under the fixtures or inside the wall cavity. You should ensure that all of the heating cables are well covered with tile adhesive.

Overcoming Space Limitations

It’s advisable to go for highly conductive floor finishes when installing an underfloor heating system in a small room with a limited area for wire and pipe installation. The ideal floor finishes are tile or stone because they can be heated to a high floor temperature. These flooring materials will help you achieve a higher heat output than what you can achieve with the soft floor finishes. It might also be necessary to use a secondary source of heating to achieve a higher heat output depending on the heat loss of an area. You can increase the total heat output in your bathroom by using wall heaters or heated towel rails.

The structure of the flooring material and the molecules within it will influence the heat flow. Flooring materials like tile and stone have a dense structure, which means that heat will travel much quicker. Flooring materials like wood have a more porous structure that will make the heat travel much slower.

Call Us Today

If you would like to know the heat output of your underfloor heating system, you should contact us. We will help you calculate the heat loss and determine whether the floor heating system will produce ample heat to warm up a room. We will also advise you on the best underfloor heating system that will meet your heating needs. We have helped many homeowners achieve an optimum heat output by choosing the right floor finishes and ensuring that their homes are well insulated. We are just a phone call away; our polite and caring experts are ready to help whenever you need them.