Mark Dowdeswell, Senior Category Manager at Uponor, outlines best practice when installing its Minitec low profile UFH system.
Underfloor heating (UFH) was once seen as an aspirational product. However, it is becoming increasingly seen as a standard must-have, with the market growing at over 13 per cent annually. The reason more and more people are choosing underfloor heating is being driven by a number of factors, including an increased awareness around energy efficiency as well as how underfloor heating provides economic benefit, increased thermal comfort and also saves space in the building it is installed in.
In the past, underfloor heating was reserved for new builds, with retrofitting being seen as time consuming, expensive and difficult. However, the combination of better knowledge and improved technology has led to low profile systems that are more than suitable for retrofit project thanks to the specialist heights and designs they are available in. This system can be installed on top of a variety of materials, including solid concrete, timber suspended floors or tiles. They also allow for a variation of floor coverings to be installed on top without impacting heating efficiency.
There are numerous key differences when installing a regular underfloor heating system compared to installing a low profile one. To highlight the best practices when installing a low profile system, we’ve collated a step-by-step guide to applying the ultra-thin, wet-screed based system Minitec.
Step 1
Remove any old carpet and adhesive, then clean and prime the concrete screed so it is ready for you to apply the underfloor heating panels. The panels can also be directly installed onto tiles, but they must be cleaned thoroughly and primed. For wet-screed systems such as Minitec, the primer must be compatible with the levelling compound, which will be applied at a later stage.
It is crucial that the subfloor is stable, flat and properly prepared, otherwise, it can lead to problems later on, such as damage to the floor finish. If the underfloor heating panels are to be installed on top of old floorboards, it is important to lay at least 5mm of self-levelling screed first.
Step 2
Next, fix the edge strip to the wall and lay the underfloor heating panels across the floor area. Both the edging strip and the panels of the Minitec system have a self-adhesive layer on the back to assist application and make sure the system is secure.
Remove the protective backing on the edging strip and press along the wall, starting from the right-hand corner of the room. The edging strip is provided in various profiles to help create an effective seal along the wall and floor. Remove the back from the panels to expose the adhesive layer. Attach the panel at the first corner and roll it out over the floor, making sure to apply pressure to secure the panel in place.
Minitec panels can be walked on without boarding being placed over it and once the whole area is covered, the panels can be easily shaped by simply cutting them with a knife.
Stage 3
Once the panels are down, connect the polyethylene pipes as per the floor plan, making sure the pipes are laid in loops of equal sizes. The Minitec panel allows the 9.9mm pipes to be clipped in at a minimum of 50mm centres. This is the distance between two pipes measured from the ‘centre’ of one to the next. 50mm is much closer than the typical 100mm centres and allows the underfloor heating to be more reactive, meaning it is able to heat up 50-60 per cent faster than standard underfloor heating systems. If there are any obstacles in the room, you need to alter the centres on the pipe to avert them.
When you combine the tracking within the panels alongside the flexibility of the pipes, it helps you to lay the pipes in both consistent and accurately spaced lines. Minitec panels are designed to allow the pipes to be installed in both 90˚ and 45˚ bends. To do this, simply apply firm pressure to fit the pipes into the panels’ grooves, using your foot to press them into place. With the system being so robust, you don’t have to worry about breaking the panels during this step.
Stage 4
Once these steps have been completed, it is time to install the manifold, connect the pipes and test the system. If you are connecting to the Uponor compact manifold with branch compressed connections, the pipe will need to be bent at a right-angle and pushed onto the compression adaptor. The end of the pipe, including the adaptor, is compressed onto the pipes and sewed onto the manifold.
Stage 5
Once you have the pipes in place, it is advised that you mix and pour a levelling compound on top, covering the pipes and panels. With Minitec, there are prefabricated holes at regular intervals, allowing the levelling material to flow in smoothly and bond directly with the underlying substrate. This layer is applied until it reaches just above the panels’ studs, achieving the 15mm installation height.
Compounds are available with curing times as low as 30 minutes, allowing the floor finish to be completed on the same day if required. Traditionally, hard surfaces such as ceramic tile or stone will be chosen as they are suitable materials for transferring heat to the surface of the floor. However, Minitec will work efficiently with the majority of floor coverings including carpet – as long as the combined tog rating of the carpet and underlay does not exceed 2.5 tog value it won’t affect the UFH’s ability to heat the room.
The heating system itself can be brought up to temperature just three days after laying the compound. This is also the point at which you can optimise the efficiency of the Minitec system by connecting it to the Smatrix Pulse smart control.
For further information on Minitec from Uponor visit https://www.uponor.com/en-gb/products/underfloor-heating/minitec
