Underfloor heating is slowly catching on in the UK although it is still largely reserved for prestige new build homes as it is time-consuming, and therefore expensive, to fit compared to conventional radiators. But underfloor heating does require lower temperature water than radiators and this lower energy requirement is what makes it attractive for a sustainable home.
Underfloor Heating Advantages
The other advantages of underfloor heating come from the even distribution of heat around the home and rooms. There are fewer hotspots or cold zones because there are no convection currents taking hot air around and dragging cold air behind them. This is the main disadvantage of radiators, particularly in a badly thought out installation. And of course interior design and decorating are easier as there are no visible pipes and radiators getting in the way.
However an underfloor heating installation in an existing home involves removing every floor and perhaps even raising floor heights to make room for it. This means that underfloor heating is rarely installed in an older house unless it is being completely gutted.
Basics of Hot Water Underfloor Heating
In these instances we are talking about water underfloor heating systems. These are effectively large radiators laid down and fitted beneath the floor, usually with the pipework supplying the hot water to each room going to and from a central manifold near the boiler. This centralisation makes for easier control of temperatures but further increases the cost and difficulty of the installation.
In the last ten years kits have become available to allow hot water heating to be installed in extensions to existing houses by tapping into the existing conventional radiator system. But often the boiler needs to be replaced to work with these extension kits so there yet more expense.
Emergence of Electric Underfloor Heating
Slowly, however, electric underfloor heating systems have been coming on the market in the UK. They have become cheaper and they are now available in kit form for DIY fitting. These systems comprise an electric heating element incorporated into matting which is laid on top of the base and under the flooring material. It is then connected to the existing electricity supply, although this must be done with a separate spur from the main board with a safety contact breaker.
These electric elements are much thinner than the hot water pipes so the whole installation is lower and it is usually not necessary to raise floor heights to make room for them. They can be installed in a wooden floor with joists and floorboards, something that isn’t normally possible with water underfloor heating systems (note that you do still have to raise the floorboards through).
With an electric system there is less heat build up. The electric wires are more numerous and smaller than the pipes, so there is less thermal expansion to deal with. Hot water pipes for underfloor heating are buried in a top screed layer of a floor so these electric elements are much easier to lay and fit.
The running costs of electric underfloor heating are generally higher than those of a hot water system although this is not clear cut. Different houses and boiler installations will perform differently as will different types of heating system. Energy prices are fluctuating a great deal these days, so it may not always be the case that gas heating is cheaper than electric, something that has generally held to be the case for the last fifty years or so. As the easily obtainable gas in the North Sea begins to run out this rule is even less likely to hold true.
But any cost evaluation process should take into account the installation of an underfloor heating system. There’s no doubt that an electric underfloor heating system will be a lot less expensive to install than a hot water system and might soon become cheaper than installing conventional gas central heating with radiators.
Sustainable Future for Electric Underfloor Heating?
In the future it is likely that solar panels that generate electricity will become powerful enough to power underfloor heating of this type. That will help a great deal in the quest to live in sustainable homes.