Installing A Heat Emission Plate (HEP) System

Installing A Heat Emission Plate (HEP) System

When it comes to UFH on ground floors, this tends to be done by embedding pipe into the screed. And providing it is done right, you have an extremely efficient system. However, more and more people want UFH throughout their home meaning incorporation of underfloor heating on (normally) a suspended timber floor. Many systems can do this, but this week we are covering heat emission plates.
Things to know when selecting this system.

  1. You want to try and select the thickest plate you can (the more aluminium, the better the heat transfer). Ask your supplier for the thickness of the plate. You need to be looking at 0.5 mm plates – any thinner & the transfer is reduced.
  2. The centres of the joists are important if selecting HEP’s, they need to be uniform and they cannot be an engineered type of joist. You are required to notch the joist at the end then past the pipe through.
  3. The plate size needs to match your joist (the most common size is 400mm between joists) and the plates should be slightly shorter, this is so the HEPS do not overlap and cause noise.

Ok, so you decide this system fits your building. Now it comes to the laying. The biggest mistake I see with this system and ultimately giving an inferior performance, is how the plates are laid. I have seen and heard of far too many installs where the plate has sagged in the joist. But why is this bad? Because it changes a system designed to be a conductive heat transfer to a convective heat transfer, as you are introducing an air gap between the emitter and the surface.
We can demonstrate the severity of introducing an air gap in this example. On a radiator, if you put your hand over the top of the radiator without touching it, you will find this is comfortable and would not be a problem (this is convection- you even feel the air movement as it rises). However, when you touch the radiator, this is direct contact with no air gap and the heat conducts to your hand (conduction) meaning you usually cannot keep your hand there for very long.
This is the same principle as the heat emission plates. So, you can get a severe drop in performance if the plates sag.
The best remedy is to support the underside of the plate by making a false floor by using either supported rigid insulation or build a false base with wood planks. You then want to use fibre insulation and overfill between the joist. Now when you put the plate down – they arch into the room – then staple the plate down to stop them moving and lay your pipe. I did this in my own house with great success and got a nice 27°C floor surface temperature (maximum for the floor I have) and have no cold spots. Also, my water temperature is only set to 50°C
Top tips:

  1. I found MLC was too tricky to lay because of the stiffness so use a PEX or PE-RT pipe.
  2. Make sure the plate has a light bulb profile groove and not a simple U profile groove. They might be more costly, but it stops the pipe coming out of the plate.
  3. Make sure you are notching the joist in line with building regs otherwise you can weaken the floor.
  4. Try and not step on the plates, if you do, make sure they are still sitting proudly.

If you’ve any more questions about installing Heat Emission Plates, our technical team are always here to help you out. Get in touch with us

Email Us

Call Us

Read more of our Tech Tuesday articles

View all

Follow us on social media to stay up to date with the latest industry trends, product offerings and more Tech Tuesday articles!