I can recall many occasions over the past 10 years where I have been called out and inspected a faulty underfloor heating installation, I discovered that the underfloor heating systems generally have been designed¬¬ on the border of normal operation to, I assume, reduce the overall amount of the materials required, and thereby make the cost for the project more attractive against rival companies, but at what cost to the end user?
The customer may have saved money by purchasing a cheaper system but what has been sacrificed with particular regard to the performance of the underfloor heating system? Surely the opportunity to the end user is, other than all the additional benefits of a well designed under floor heating system, to have a under floor heating system designed to maximise the energy saving potential and thereby reduce their fuel bills to a minimum.
Good underfloor heating design should take into account all the relevant energy values and the restrictions presented by the prescribed floor finishes, and deliver the energy load required supplied via the energy source with the minimum flow temperatures. This requires careful consideration and design to allow for the heat source not to be oversized as this also can be a contributing factor to the lessening efficiency of the heating system.
There are a lot of companies out there that take the energy values from published articles and tables and apply these in a generic form to create a solution to your energy needs; I believe those companies should take the more factual route, my advice to anyone seeking a high quality underfloor heating system is to ask questions like;
“What heat output per square meter has my system been designed to deliver?”
“What would happen if I switched from a tiled surface to a carpet with a high Tog value?”
“What would happen if at a later stage I switched from gas boiler to high efficiency heat pump?”
“What software did you use to design my heating system?”
There are installers just sketching there designs if that, and using a pipe centre spacing to give out a heat output recommended by the manufacturers, but are you aware of the implications if they have not taken into account for the all the important factors involved for the buildings heat requirements that can lead to over sizing. Have the pressure limits been adequately calculated for, which may cause the pumps being inadequately sized? Have they the resources to calculate the exact length of underfloor heating pipe and heat loss running in each zone?
There’s an old saying that still stands true today, “buy cheap, pay twice” but in this instance it’s more like “buy cheap, buy several times” because how are you going to quantify the cost of an inadequately installed underfloor heating installation after your finished floor surfaces are down. I believe very careful consideration needs to take place, that you have the right person with relevant experience, because you need to get the maximum payback from your underfloor heating and more importantly I believe as new energy sources come along how will your underfloor system cope with this new technology?
My question is as always potential clients considering an underfloor heating system is this; Price or Performance, buyer beware.