Heat Mat Press Release
Part L changes and UFH systems
David Green a Director at Heat Mat looks into the effects the changes to Part L of the Building Regulations will have on underfloor heating systems.
The new documents for Part L of the Building Regulations (Conservation of Fuel and Power) introduce many new standards for heating. Included are new minimum provisions for the control of underfloor heating systems and the specification of the installation and additional insulation. The overall changes to Part L are a vital step towards the Government's target of reaching zero carbon homes by 2016, and will result in significantly more energy efficient properties with the obvious benefit of reduced fuel bills and carbon emissions. Electric underfloor heating systems lend themselves particularly well to being used for installations covered by the new Regulations, particularly as they run at high efficiencies for converting electricity into heat.The Regulations themselves introduce a number of specific requirements for installers and specifiers of underfloor heating systems.The main points are covered below.
Underfloor heating controls
Each room is required to have its own temperature control device. However, where adjacent rooms have similar functions it could be acceptable for them to share a controller. In bathrooms and en-suites which share a thermostat with a bedroom, the bathroom or en-suite will have to have an additional controllable heat source installed, such as a towel rail or radiator. For this reason it is highly preferable to control each underfloor heating area separately. Heat Mat can offer wireless thermostats to simplify the installation in these circumstances. All systems will need to have weather compensating controllers fitted which take into account the changing seasons when calculating the time to start heating. In areas where an undertile heating system is being used as the main heat source it is a requirement to install programmable thermostat/timers which incorporate a manual override feature, so the air temperature of the room can be easily controlled. For dwellings over 150m2 at least two space heating zones must be created, each having separate temperature and on/off controls. Heat Mat's BEAB approved NGT thermostat is fully compliant with all of these requirements, in addition to being simple to install and use.
Insulation requirements
Where underfloor heating is installed there is now a requirement to ensure a significant level of insulation is present beneath the system, to limit downward heat loss.
System requirements
Where electric underfloor heating systems are being used as storage systems the minimum screed thickness on top of the cables is now 65mm. Direct acting underfloor heating can not have a screed layer deeper than 60mm, to ensure the heat reaches the room reasonably quickly. Under-tile electric heating must now have a thickness of less than 4mm. Some systems currently on the market breach this limit. The Regulations appear to state that the heating cable must be pre-spaced as a heating mat, rather than being supplied as a loose cable.
Central control systems and home automation
The next big thing in underfloor heating is the move towards rooms being centrally controlled, whether by a proprietary thermostat or a home automation system running KNX or a similar protocol.With this in mind Heat Mat has introduced a new central control unit which allows every room in a house to be wirelessly controlled from a central point. The system is based around the company's simple to use NGT thermostat, and allows up to 15 rooms to be controlled from a central point whilst retaining the ability to adjust the temperature in each room locally.The product is quick to install, available in more than 50 different finishes and also includes a wireless relay point for the control of panel heaters or similar devices if required.
