This blog was published on our Blogger account on 4 Feb 2015, with a few minor edits on 22 Sep 2020. Our philosophy on the subject has not changed.
When you're considering a new build, no matter what its purpose, there are certain things you have to get right from the start. Many people are surprised that, as underfloor heating and renewable energy specialists, our mantra is "Insulation, insulation, insulation." The reason for this is that the insulation in your floors, walls and roof are critical to keeping the cost of your heating to a minimum, and the occupants' comfort to a maximum. Heat easily seeps through the fabric of the building if you don't get this right, and you end up heating outside as well as inside; literally heating space. And it's not rocket science to work out that in the case of the floors and walls, you won't be able to change it later without major upheaval.
The above photo shows a poorly insulated house. Note the single glazed pane on the ground floor window, with a much higher heat loss than the other double glazed panes. Also, this house has had cavity wall insulation that has not completely filled the cavities, hence the blotching effect where heat is being lost through the walls. There is a lot of heat also being lost from the chimney, but that is already outside the house anyway.
This time the photo shows a very well insulated house with hardly any heat loss except for the top sections of the ground floor windows (perhaps due to the windows having trickle vents). It is a pretty safe bet to say that this house is heated by radiators because the hotter air with the greater heat loss is at the top half of the rooms. With underfloor heating this effect would not be so noticeable.
If you intend using renewable energy devices, and why wouldn't you, we always recommend installing insulation to 'better than building regulations' u-values. It is all to your/your clients' benefit in the end. A little extra money spent up front, will save money on fuel to heat the building for many year to come, and which, if insulated well, may not need much heating at all.
It's all a bit like taking a long journey, I suppose; any car worth its road tax will get you from A to B. An old banger will get you there eventually, a run-around vehicle (what I call a shopping car) will get you there too, but you may prefer to spend a bit extra and get there in style, comfort, and efficiency.
An underfloor heating system is more efficient to run than the old banger/Moggy Minor that is a radiator system. Let's face it, who hasn't had a moan that all the heat from your radiator system seems to heat the ceiling more effectively than it heats where you sit. After decorating her living room, and noticing the lovely warmth as she ascended the ladder, my neighbour often said that she wished she could put all the furniture up at ceiling level where the heat was. We never hear that from our UFH customers, or their cats.
Having discounted the old banger option, you then get to choose from the shopping car to luxury, performance and in some cases sheer bling, ranges of underfloor heating. Some think that all underfloor heating systems are the same, and that by paying a lower price you'll still get the same performance, but this is not the case. Not all underfloor heating systems are the same, there are different qualities of equipment and different levels of control sophistication. Whether you choose to spend less or more is obviously up to you, but like I said at the beginning, you have to get it right from the start.
PC-W, BUH 04.02.15 (minor edits 22.09.20)