A lot of people live in old houses. In the UK, 62 per cent of all dwellings were built before 1965, and 35 per cent were built before World War II [1]. New builds have to meet minimum environmental legislation and take into account energy performance certificates which demonstrate efficiency. This legislation was not around when older houses were built, so it is important to be able to modify your old build to become more energy efficient as an investment towards environmental sustainability and as to improve your energy performance certificate when you come to sell. By improving energy efficiency in your old house, you will also reduce your utility bills, which will inevitably increase as energy supply becomes more expensive. There are several tips and tricks to improving the energy efficiency of old houses and these will be discussed in this article.

Ventilation

Older homes are quite often deliberately draughty, and not poorly built, as one might expect from a draughty old building. Old homes are made from porous materials such as brick, timber and limestone. These materials will soak up water and dry out again when well ventilated. Therefore ventilation is vital to ensure an old home does not become damp and mouldy. New builds, on the other hand, are made from water resistant materials such as cement and plastic and do not tend to be draughty or damp. Here are some ideas for improving ventilation in your old home:

• Draught stripping is the placing of a strip of material over a draughty door, window or other crack to stop cold draughts from coming in and taking warm air out.
• Extract ventilation is the use of extraction fans in rooms which are prone to dampness such as kitchens and bathrooms. This allows the damp air to be pulled out of the room whilst maintaining heat.
• A trickle vent can be installed when replacing window frames. It is a small adjustable opening which allows the home owner to manually control ventilation in a room.
• Ventilate loft space. The original purpose of any loft was to act as a cold ventilation space that would expel any damp caused from rain or condensation [2]. Therefore it is important to maintain ventilation in this space and if converting your loft, you will need to consider how the house will ventilate itself when this cold area is removed. Special roof vents can be installed by roofers.

Insulation

Insulation plays a big role in improving the energy efficiency of an old house. However it must be done in such a way as to respect the ventilation of the property. Here are some insulating ideas for consideration:

• Internal wall insulation. This involves attaching insulated plasterboard to the inside walls of a house. This can be done in many ways. Where there is a lack of floor space, the plasterboard will be applied directly to the inside wall. Where there is more room, the plasterboard will be applied on top of a secondary insulation layer.
• Double glazed windows use two sheets of glass with a gap between them which creates an insulating barrier [3]. This keeps your home warmer.
• Cavity wall insulation can save you around £110 a year on your fuel bills [4]. This is the filling in of the gap behind your walls with insulating material if your house was built after 1920.
• External wall insulation involves adding a decorative facade to the outside of your home which has insulating properties.
• Insulate your loft by laying down special insulating quilts or get a professional to blow fire safe insulating material into your loft space.
• Insulate water pipes to retain heat so keeping hot water hot for longer.
• Insulate floors by laying a mineral wool underneath and filling in skirting board and floorboard gaps with sealant.
• Cheaper insulation options include putting up blinds and heavy curtains, which can almost halve the heat loss in old homes [5].

Heating

Upgrading your heating system in your old home can show drastic improvements on energy savings and utility bills. Three key improvements are:

• Insulate your hot water cylinder to keep water hot for longer and to save on reheating the water.
• Improve controls on your heating system. By doing this you can take more control of the amount of electricity being used to heat hot water for example, control room temperature so it is maintained at a minimum level, control when boilers are heated to take advantage of cheap electricity tariffs on Economy 7.
• Fit a replacement combi boiler. A combi boiler is both a high-efficiency water heater and a central heating boiler, combined within one compact unit [6]. No separate hot water cylinder is required as hot water isn’t stored but heated directly from the cold mains. A condensing combi boiler is more efficient due to its ability to extract more heat from the flue gases normally lost to the environment through the flue system [7].

Low carbon energy sources

If you wish to source your energy from a lower carbon option, then you will have to undergo planning permission. For older houses, this can be a tricky area, especially if the house is historically recognised or if you live in an area where a wind turbine or solar panels on your roof would present a problem to the overall look of an area. Low carbon and renewable energy solutions which potentially have the least visual impact include: ground source heat pumps; air source heat pumps; and water turbines [8].

Some inspiration

For some inspiration on how you can improve the energy efficiency of your old home, visit www.sustainable-energyacademy.org.uk [9] which aims to have an old retrofitted home publicly accessible within 15 minutes of everyone as part of their Old Home SuperHome project.

References

[1] Cook, M.G. (2009) Energy Efficiency in Old Houses, Crowood Press Ltd.

[2] What Price? (2010) Keeping a Loft Conversion Well Ventilated http://www.whatprice.co.uk/advice/building/loft-ventilation.html

[3] Energy Saving Trust (2010) Glazing http://www.energysavingtrust.org.uk/Home-improvements-and-products/Home-insulation-glazing/Glazing

[4] Energy Saving Trust (2010) Cavity Wall Insulation http://www.energysavingtrust.org.uk/Home-improvements-and-products/Home-insulation-glazing/Cavity-wall-insulation

[5] Energy Saving Trust (2010) Insulation Most Important for Preserving Old Homes http://www.energysavingtrust.org.uk/Resources/Energy-saving-news/Insulation-and-glazing/Insulation-most-important-for-preserving-old-homes

[6] Worcester Bosch (2010) What is a combi bolier? http://www.worcester-bosch.co.uk/homeowner/products/what-is-a-combi-boiler

[7] Combiboiler.net (2010) Combi Boiler Information http://www.combiboiler.net/

[8] Peak District National Park Authority (n.d) Conserving Your Historic Building: Sustainability and Historic Buildings http://www.peakdistrict.gov.uk/sustainabilityandhistoricbuildings.pdf

[9] SEA (2010) Sustainable Energy Academy http://www.sustainable-energyacademy.org.uk/