How to Install Underfloor Heating

It is important to ensure you install underfloor heating properly. If you don't, it could damage the floor, voiding its warranty.

Your underfloor heating system will have its own guidelines to follow. However, there are some general tips you can follow. Below we have provided a brief installation guide for wet and dry systems.

1. The Different Types of Heating Systems

There are two types of underfloor heating systems you can install. These include wet and dry systems. Both can be used alongside different types of flooring.

A wet system, also known as a hydronic system, pumps warm water throughout the pipes under the floor to provide heat. A dry system, also known as an electric system, heats the floor using mats with electric coils.

There are pros and cons to be aware of with both types. Wet systems are cheaper to run, but you will need to raise the floor to install them. Dry systems are typically better for smaller areas. They are easy to install, but they are more costly to run.

It is important to weigh up the pros and cons of each system prior to deciding which one is right for you. You will also find some types of floors can only be installed with specific underfloor heating types. So, always check manufacturer guidelines prior to installation.

2. Preparing for Installation

It is best to check the room is well insulated prior to installing underfloor heating. This ensures the heat will not be wasted. The subfloor should also be clean and free from debris. Insulation will need to be installed under the system to prevent heat escaping through the foundations.

If you are installing an electrical system, a professional will need to come to fix it to the mains.

3. How to Install a Wet Underfloor Heating System

Wet underfloor heating systems are more complex to install than dry systems. For this reason, we advise hiring a professional to fit it for you. To do it yourself you will need to identify where the manifold for the system will go.

If you are installing the system in one room, place the manifold in the same room. Larger systems multi-room systems will require pipework to run through walls or doorways. You will need to drill holes for both the flow and return pipes into the room. After drilling, clean up any debris.

Lay down the insulation before installing the system. When ready, fix the manifold into position against the wall. Make sure the unit is level. It should be fitted 600mm off the floor, allowing the pipes to be easily fitted.

Avoid placing the manifold in a corner. You may need space around it for future maintenance. Once it is in place, connect the manifold to the water supply. You can do this via the mixing valve and pump. Make sure the isolating taps are in the switched off position. If you want to use radiators alongside underfloor heating, a zone valve will be needed.

Next it is time to lay out and secure the pipework. This can be done in numerous ways. However, the most popular method is to use grip rails. Lay out grip rails at a 90-degree angle where you want to lay the pipes. Make sure they are positioned correctly before securing them in place. When you are ready to secure the pipework down, you will also need staples.

To finish, a layer of screed should be applied. Contact an expert to determine which type of screed to use. It should be applied over the insulation. Allow the screed to dry naturally after it has been applied.

4. How to Install a Dry Underfloor Heating System

There are different types of electric systems. Therefore, the method used will depend upon your chosen system. A loose wire system would best suit irregular shaped rooms. They come with cables which can be placed around furniture and objects.

Electric UFH mats are the most popular type used by homeowners. These are easier and quicker to install in standard, larger rooms. Matting systems can be purchased in 150w or 230w options.

If installing in a wet area, a fully earthed system is ideal. These feature an integrated safety mechanism. An expert will be able to advise you of which system is right for your room. We will focus our attention on installing electric matting systems. These are the most commonly used by homeowners.

5. Installing Electric Matting

If you are installing the underfloor heating in a cold room, the higher 230w option is ideal. Most rooms however will benefit from the 150w option.

If you need to install insulation, the insulation boards should be fitted first. Glue them down with suitable adhesive. Apply the matting using its built-in self-adhesive tape or backing. Stick it directly on top of the insulation boards.

Screed over the matting to finish. This type of installation is better suited to permanent floor coverings.

This is a basic guide for installing wet and dry underfloor heating systems. We do recommend sticking to the dry systems if possible. They are much simpler to install, whereas a wet system is best fitted by a professional.