Questions and answers

What is underfloor heating?

Underfloor heating is a heating system that uses heated water to warm the room. Its basic element is the pipework, which must be durable and made of high-quality material. For this purpose we therefore  recommend polybutene, which meets the quality and safety criteria,  is resistant to corrosion and dampens noise in the pipework. Heating water flows through the pipes laid in the floor and spreads heat across a large area. Even a larger house can be heated in this way. The water is heated by a boiler or another heat source. A condensing boiler is the most suitable, as its high efficiency is supported precisely by low-temperature systems.

You will find the complete range in the underfloor heating category – system insulation boards, pipes, manifolds, controls and electric heating mats.

What are the advantages of underfloor heating?

Full control – Underfloor heating gives the homeowner the option of setting the temperature in individual rooms or zones  independently of one another using programmable room thermostats, which provide full control and comfort.

In most households, for example, some rooms such as the kitchen and living room are used more often than others. Once a thermostat is installed, you can choose in every room of the house what temperature you want and for how long. This reduces the amount of energy used.

Energy savings - Underfloor heating is becoming ever more popular because it is an energy-saving heating option. Bear in mind that thermal comfort with underfloor heating is achieved at a room temperature 3 – 4 °C lower than with radiator heating (which also reduces energy demand by approx. 25 – 30%). It follows that with underfloor heating we achieve the highest level of thermal comfort at temperatures of just 20 – 22 °C.  

Free walls and an interior designed just as you wish - Because the radiators are removed, underfloor heating gives the homeowner complete freedom in designing the interior of the room.

Improved air quality – Underfloor heating stands out for its minimal air movement and its large share of radiant heat. It is therefore a good choice from a health point of view, especially for people with allergies and asthma.

Return on investment

This is calculated from the savings achieved by using underfloor heating compared with the original way of supplying heat. An important part of underfloor heating is the installation of a condensing boiler, which works at lower temperatures and therefore with more pronounced condensation and higher efficiency. Depending on the condition of the old boiler, such a replacement can save up to half of the heating costs. When a condensing boiler is installed, spending on gas heating falls, because a condensing boiler is up to 15 % more efficient than conventional boilers, as it also uses the thermal energy of the water vapour in the flue gases, which leaves a non-condensing boiler unused through the chimney into the air.

Is underfloor heating complicated to install?

Installing underfloor heating is very simple and flexible. It can easily be added to an existing building or installed as the main heating system in a new project.

It can be used together with traditional radiators or as the sole heating system, with either a condensing boiler or one of the new renewable heat sources.

Many factors  can have a significant influence on your decision. These include, for example, the number of rooms to be heated, the size of the rooms and so on.

If you want the best possible underfloor heating solution for your home, you need to choose the right specialist, who will calculate the heat losses and the pipe layout on the basis of your plans.

Frequently asked questions.

We have collected the most frequently asked questions about underfloor heating for you. We hope they will help you make your choice.

Why should I choose underfloor heating instead of a traditional radiator system?

There are many advantages to installing underfloor heating instead of radiators. One of them is that underfloor heating works at temperatures of around 35 °C - 50 °C,  whereas a radiator system works at 70 °C -80 °C, and for that reason underfloor heating has lower running costs. Properly designed underfloor heating can save up to 40% of normal costs.

Can I have both underfloor heating and radiators?

Yes, of course. It is common to have underfloor heating installed on the ground floor with radiators installed on the first floor.

However, with costs having fallen in recent years and given its many advantages, underfloor heating is increasingly being installed throughout the whole property wherever possible.

Can I use parquet or carpet over underfloor heating?

If a textile floor covering is used, the heating designer must allow for a partial reduction in heat output at the design stage. Carpets with a pile height over 10 mm and a rubber backing, PVC with a felt underlay and softwood parquet are not recommended (the resistance must not exceed 0,15 m2.K/W). We recommend wooden parquet with a max. thickness of 15 mm made of well-dried hardwood. For mosaic parquet, a max. thickness of 9 mm.

What insulation is normally laid under underfloor heating?

Rigid polystyrene is normally used, 30 mm thick for an upper floor and 60 mm for the ground floor (two 30 mm polystyrene boards are used, laid so that they overlap). The density of the polystyrene should be 20 kg.m-3 and its compressibility must not exceed 10% of its thickness at a pressure of 10 kg/cm2. Care must also be taken in areas without a basement, where waterproofing is used, to ensure the polystyrene is not in contact with primers based on cyclic compounds and solvents, which would destroy the polystyrene foam. In that case, rubberised bitumen with glass-fibre fabric must be used as the waterproofing layer.

Planning underfloor heating - the design

Many factors are taken into account when assessing whether an underfloor heating system should be installed in your particular project. Even once you have decided that underfloor heating is right for you, it is important to know what steps to take to make sure the system works as it should and delivers the best possible efficiency and output.

The information below will help you make the right decision about which type of underfloor heating system is right for you, and will also help you identify the  accessories you will need for the underfloor heating system to work.

Types of floor construction

The type of floor construction may vary depending on where you are installing the underfloor heating. Most projects use a conventional concrete screed; however, if you want to install underfloor heating in an attic between load-bearing timber joists, a conventional concrete screed would be unsuitable in terms of load or construction (the height of the habitable attic is too low and the floor cannot be raised).

Fixing the pipes in the floor

Two methods are commonly used in practice – fixing with clip rails and fixing with a system insulation board. Fixing with a system insulation board is the most advantageous in terms of cost and time. The pipes are completely encased in concrete, and the system boards overlap one another when laid, which prevents concrete from seeping through and thermal bridges from forming.

Floor coverings

Stone and ceramic tiles

Tiles are generally considered the best floor covering for use with underfloor heating. Both types have very good thermal conductivity.

Wooden and laminate floors

All types of wooden floor can be used with underfloor heating, but some are more suitable than others.

Rules for wooden floors:

The initial moisture content of the wood should be less than 8% to prevent warping or shrinkage.

The initial moisture content of the screed should be below 0,5%.

The surface temperature of the wood should not exceed 27 ^oC.

Softwood such as pine should be avoided.