Energy Efficiency Measures

EWI systems help buildings to retain heat by affixing an extra layer of weatherproof insulation to the outside walls. They are typically used if the wall doesn’t have a cavity that can be fitted with insulation. (This is quite common on older property types, which can lose around 45% of their heat this way.) Besides preventing heat loss, EWI systems offer other important advantages.

• They can improve the property’s external appearance, using a choice of coloured renders or brick-effect finishes.
• They provide a weatherproof surface that prevents damp and draughts from entering the home.
• They can keep the property cooler on hot summer days.
• They don’t involve major disruption to the home’s interior, redecoration, or any loss of interior space.

IWI systems are another form of insulation suitable for use on solid walls (i.e. without cavities.)  Like EWI systems, they trap heat but the insulation material is affixed to the interior walls instead. That reduces the internal floor area slightly, and it means that anything attached to the existing internal wall (shelves, switches etc.) will have to be moved. It also means having to redecorate. IWI systems should help to reduce draughts but won’t improve the weatherproofing of your home. However, IWI is sometimes the only solution – for example, if space outside is limited or if planning restrictions prohibit anything from changing the outward appearance of your property.

These are quite simply a mix of EWI and IWI. For example, it might not be feasible (or permitted) to install EWI to the front of your home, but it might be okay elsewhere. In that case, you might choose to fit IWI to the front elevation, and EWI to any other walls.

The walls of most modern residential properties are built with a cavity in between the inner and outer layer. For example, the inner wall might be made of blockwork, while the outer is made of brick. In any case, the gap between can usually be filled with insulation material to improve a property’s ability to hold on to its heat. The installation process is often quicker and less disruptive than when using solid wall insulation systems.

The Energy Saving Trust estimates that an uninsulated home will lose about a quarter of its heat through its roof. Insulating your loft to the recommended thickness is one of the cheapest and most effective ways of cutting your bills quickly. The National Insulation Association (NIA) notes the following guidance.

“Room in roof” refers to a loft space that has been converted for use as living space. Again, fitting suitable insulation will help to keep such spaces much more comfortable and prevent heat from being wasted. Since the insulation needs to be overhead (above what will probably be a sloping ceiling) insulation will often take the form of mineral wool or insulation boards, protected behind plasterboard. Ventilation issues also need to be considered carefully.

Homes will sometimes lose heat through their ground floor, in which case, fitting floor insulation can prevent unnecessary losses. Floor insulation is also invaluable if you have an underfloor heating system. It’s much less important to fit it on upper floors, except where they are built above open or unheated spaces.

Draughts can often be eliminated quickly, cheaply and easily, making draught-proofing one of the most cost-effective ways to cut your bills. Simple measures, such as re-sealing window frames or fitting draught excluders to doors and letterboxes can deliver big savings. Often, tasks can be tackled on a DIY basis but be aware that there will always be a need for adequate ventilation, particularly in rooms that have fires or where there is a risk of damp and condensation (e.g. kitchens and bathrooms.)

Older doors and windows can lose heat in two key ways. First, heat may escape through the glass and other materials (plastic, wood etc.) Second, they may have gaps that allow draughts, which means cold air getting in, and warm air getting out. Modern replacement doors and double- or triple-glazed windows will generally be much better at retaining heat, and they should also be free from draughts – delivering a twofold saving.