Find your way around the underfloor heating options
Are you planning your home and deciding between radiators and underfloor heating? At first glance it may seem that the only difference is that radiators are in plain view while underfloor heating is “hidden beneath the surface”, but there are in fact several fundamental differences. A radiator heats a much smaller area, so its efficiency drops while energy consumption rises, whereas underfloor heating, laid beneath the whole floor of the room, warms the space more evenly and, combined with a well-insulated house, gives you an energy-efficient home. What is more, it does not take up any of the room the way a radiator does. So how do you find your way around the range of underfloor heating on offer?
You will find the complete range in the underfloor heating category – system insulation boards, pipes, manifolds, controls and electric heating mats.
Types of underfloor heating
If you have decided to make walking barefoot around your home more pleasant by choosing underfloor heating, you can pick between electric and water-based (wet) underfloor heating.
Underfloor heating powered by electricity uses resistance cables or mats connected to the mains. It is easier and cheaper to install, but because electricity is a more expensive source of heat than natural gas, this type of underfloor heating is recommended for smaller areas such as bathrooms.
Compared with electric underfloor heating, water-based heating is more demanding both to install and to pay for, but in the long run it is clearly the better investment for households with a gas boiler. Another significant advantage is that such a system can be connected to energy from renewable sources, such as fireplaces with a back boiler, wood boilers, heat pumps or solar collectors.
Water-based underfloor heating and its options
Depending on the planned ceiling height of the room and on how much load from a concrete screed the structure can bear, customers choosing water-based underfloor heating decide between a wet and a dry system.
In the so-called wet system, which consists of screed, a heating layer and an insulation layer, the total thickness comes to 10 to 15 centimetres. Even here, however, you can choose between a high and a low profile of underfloor polystyrene.
For underfloor heating with a higher profile we recommend the UHP55 system insulation board. It is 5.8 cm thick and allows pipe spacing in multiples of 7.5 cm. If, on the other hand, you need to fit into a shallower floor build-up, the ideal solution is the UHP53 system insulation board, 3.6 cm thick with pipe spacing in multiples of 5 cm. Whether you choose the higher or the lower profile, both options are best combined with the DP50 self-adhesive perimeter expansion strip, UHP 16 polybutylene pipe or PEXALPEX multilayer pipe, which is made up of several layers, with the aluminium layer in the middle acting as an oxygen barrier that stops oxygen getting into the heating pipework.
The dry system requires a total layer thickness of roughly 11 to 12 cm. The solution for this option is polystyrene for underfloor heating 30 mm high, with pipe spacing in multiples of 12.5 cm and a heat-reflecting layer made up of heat distribution plates.
Preparing and laying water-based underfloor heating
A cabinet is fixed into the prepared opening in the wall, and a manifold with two bars is mounted on the guide rails inside it: the bar with flow meters, which supplies the hot water, goes at the top and the bar with valves at the bottom.
With the wet solution, polystyrene is laid on the reinforced concrete base and, to allow for the thermal expansion of the concrete, a self-adhesive perimeter expansion strip with a foil that stops concrete seeping in is stuck around the walls. If you choose polystyrene for dry underfloor heating, UHPS heat distribution plates are placed in the system board. If the floor finish is to be ceramic tiles, the plates are laid in every second groove; for a floating floor, in every groove.
Before the polybutylene pipe is actually laid, its start has to be threaded under the guide rail in the cabinet. We recommend laying the pipe in a “snail” (spiral) pattern; for a planned spacing of 15cm, for example, lay the pipe at 30cm centres, because on the “way back” it will run down the middle, which gives you the 15cm spacing.
Once all the circuits have been laid, the pipe is connected to the manifold, with the hot water flow fixed at the bar with the flow meters and the return below it. Make sure that the flow and return of each circuit always sit one above the other in the manifold. For easier checking we recommend labelling each circuit with a number and the name of the room.
In the next step, for wet underfloor heating, the heating screed of coarse-grained concrete is poured; once it has fully set, a 1 cm thick floor finish is laid on it, which can be either a floating floor or tiles. If the floor is expected to carry heavy loads, we recommend adding extra reinforcement before the screed is poured. After the underfloor heating has been concreted in, the floor finish laid and the plastering and painting completed, the frame with the door is fitted and the sliding plate at the bottom of the cabinet is lowered onto the finished floor. If you have chosen dry underfloor heating, at this point E25 boards with a total thickness of 25mm are laid on the surface and joined with adhesive and screws.
Now nothing stands in the way of switching on your underfloor heating and enjoying the warm feeling of a heated floor under your feet.
Quality and expertise from professionals
Living in a home of our own, and the choice of heating that goes with it, is a decision that can improve the quality of our living for a very long time. Our comfort and heating costs should therefore, from a long-term perspective, take into account the choice of supplier, its product range and the service it offers. Atria SK, s. r. o., an online retailer, has specialised mainly in heating technology since it was founded in 2012. Its portfolio of brands includes well-known names such as JUNKERS, PROTHERM, VAILLANT, VIESSMAN and many others. It currently also sells to the Czech Republic and already has business partners and customers in Poland, Slovenia and Croatia. Its primary aim is to give its customers enough information and alternatives to make decisions on heating technology that they will be happy with, and its technical support does not end at the moment of sale.
If you need advice on which solution is best for your flat or house, do not hesitate to contact us at info@atria.sk.