On this site we are grouping the "measures" which can improve your home into the following groups:
Draughts and Ventilation
All houses leak air through the external surfaces to some extent, both in and out. Cold air coming in is often called a draught if it is felt by the occupants. If it is somehow controlled by vents or open windows then it is often called ventilation. A small amount of ventilation is essential to avoid air becoming stale and causing mould. For all the air that comes in via draughts and ventilation, the same amount escapes taking with it any heat that home owners have added to it. In the UK, it is common for the volume of a house to be exchanged with outside air six times per hour – that means reheating the entire volume of air every ten minutes. Hence, it’s a good idea to reduce leaking air to reduce draughts and heat loss, but not so much that essential ventilation stops.
Houses are necessary to provide security and shelter from the elements. Comfort is optimised by applying energy of some kind to heat houses; this energy can come in a number of forms and common sources in the UK are: coal, oil, gas, electricity and wood.
Heat can be delivered throughout a house in a number of ways, such as radiators, storage heaters, hot air and direct heating such as fires or electric heaters. As heating of some kind is essential it makes sense to select an efficient option or combination of options. Choices depend on lifestyle, access to energy sources, construction type, heat delivery system and cost, so it is not necessarily straightforward but worth the effort in getting advice.
Keeping Heat In
Heat can be lost from a house in two basic ways: carried out with leaking air, or conducted through the the walls, roof and floor. As it costs to heat the inside of the home, it makes sense to try and retain as much as possible of that heat by limiting its loss.
As there are two basic ways of losing heat, so there are 2 ways of stopping it. Preventing leaking air means plugging the gaps through which air leaks. Stopping it being conducted means adding insulation to the envelope between outside and inside. Stopping heat loss means that a house needs less heating to maintain the internal temperature.
Electrical lighting has been around so long it is easy not to give it a second thought. The energy that a light burns is down to two things, the power rating of the light and how long it burns for. So, even if the lights in a house are not changed, using them less will reduce energy use. However, the power rating of modern low energy lights, particularly LEDs, can now be up to about 1/10th of older lights. Hence, changing to low energy lighting, and using less, both contribute to using less energy.
Managing Energy and Water
The energy and water provided to modern housing is often metered, and so it is straightforward to know how much we are using. Indeed, with smart metering we won’t even need to open the meter boxes. Knowing how much we are using allows us to know what it is costing and to monitor the reductions caused by any changes we make. Just by monitoring usage, and thinking about what we are doing significant savings can be made often without radical limitations on lifestyle and comfort.
Solar and Renewable Energy
Energy comes in many forms. It can be stored in a material, such as coal, oil, gas and wood and these can be convenient energy sources. Alternatively, it can be something that is active and has to be captured in some way, such as solar energy and moving water and air. Unfortunately, coal, oil and gas have taken millions of years to create and once used, cannot be replaced. Other sources such as solar, wind and water can be thought of as renewable in that they will not run out. Wood is also considered renewable, if does take a few years to regrow trees but not millions like coal, gas and oil.
Windows are necessary for light, but what do they do for energy? It is difficult to make windows as good as walls for stopping air loss and retaining heat and so often they are an energy weak spot between inside and outside. However, they also allow solar energy into the house and so if sensibly placed can be a free heat source, known as solar gain. Hence, there are a range of options concerning windows to limit air leakage, heat loss and maximise solar gain. While window locations are dictated by the design of a house and changes can be very difficult, there are things that can be done to reduce heat loss and to increase solar gain.
Building and Changing your Home
It might seem that building from new is the only option when it comes to energy efficiency, but not many can do that and so most people will need to make changes to existing houses. Knowing what to do on a limited budget to make best effect can be a daunting task, and each house will be different. It starts with understanding what the house does with the energy that is pumped into it, and then how best to provide that energy. This site gives some simple tips about how to think about energy and what options might prove suitable for individual situations.