WALLS Three common wall types are described below, with their insulation solutions.

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1 APPENDIX 5: Building Envelope Insulation is vitally important for temperature controlled buildings. If fuel (and therefore money) is being used to heat a building, less fuel (and money) will be used if the building is well insulated. Insulating a building can be a very different task depending on the type of building. There are many different ways that walls can be constructed, and each comes with its own optimal insulation type. WALLS Three common wall types are described below, with their insulation solutions. SOLID WALLS Older buildings, constructed before the latter half of the 20th Century, tend to be either completely solid, or have a badly constructed cavity which cannot be effectively filled. Solid wall insulation is generally suitable for properties built before the 1930s (approx). Since solid walls are made up entirely of brick or stone, they do not have a gap to fill with insulation, unlike cavity walls. Since there is no cavity to fill, the insulation must be fixed to the wall, either on the outside of the property, or the inside of the rooms. The benefits It retains up to 45% of household heat It can save a household up to 380 a year on heating bills It improves the thermal efficiency of a property to the same standard of cavity wall insulation It acts as a noise barrier It could increase the value of a property CAVITY WALLS In later constructions, walls were built with a gap between two layers of brickwork, or brick and breezeblocks. These cavities can be filled with insulation in a relatively simple procedure. The savings for installing this kind of system would be significant (around 10% - 15%). Cavities can be filled with insulation without disturbing the look of the outside of the property, or anything on the inside. This is achieved by drilling small holes in the outside of the brickwork and squirting insulating foam into the cavity. This is made even by having a series of holes across the expanse of the wall. The marks left are very small and difficult to notice if you aren t looking for them.

2 A very cost effective way to save energy by installing cavity wall insulation would be through the governmental grant Green Deal, or the Big Issue Funding. For more information, please visit: DECC Green Deal Summary Proposals Big Issue invest - Loan Finance TIMBER FRAME CONSTRUCTION To insulate the Timber-Frame construction is a really big improvement regarding the efficiency of the building. The most effective and least expensive is the Inside-out method: This method is the least expensive and offers the most flexibility for contractors involved with the project. Initially, the building is wrapped with rigid foam sheets to provide a thermal break. Then a 2 x 4 stud wall is built on the outside of the rigid foam. Spray-applied foam is then applied in the bays of this wall. The Inside-out method offers several advantages: It costs less then stressed-skin panels. No crane is necessary for installation. It is easier for electricians and plumbers to complete their work. Carpenters are able to install blocking to hang cabinets without the limitations imposed by stressed skin panels. GLAZING Excessive and uncontrolled infiltration of air is often the largest source of avoidable heat loss from buildings. It can account for 60% of total heat loss. Cold air infiltrates through the cracks that surround all doors and windows, while warm air escapes through vented skylights and fans. About a third of the energy used to heat a building is used to heat the infiltrating air. Example of Inside-out method CLEANING WINDOWS Consider cleaning the windows and or roof lights, to increase the amount of light coming through and therefore reducing the dependency on using artificial lighting. Clean windows allow more light into the building, helping to make it energy efficient with longer daylight hours while the heating season isn t quite over. In the summer, clean screens can be used to ensure fresh air enters the home without the bugs and debris from the past winter s wrath. Cleaning condensation off windows will help to reduce the water content of the air in the room, which will make the room feel more pleasant. Proper ventilation will prevent the build up of this condensation. ENERGY EFFICIENT DOUBLE GLAZED WINDOWS Double glazing provides an excellent solution to keep your building cool in summers and warm in winters. It also ensures that noise level remains low. Double glazing has quickly become one of the most popular and useful form of glazing worldwide.

3 Double glazing is essentially two layers of glass placed together in a window frame. Between both layers of glass, a space exists, therefore reducing heat transfer through glass. When glass panes are placed together, they are known as double glazed units of glass. The glass has thermal and acoustic properties, allowing it to form an excellent source of insulation whilst simultaneously allowing the light to enter your office. It noticeably helps to reduce your electricity bill. If everyone in the UK who could install Energy Saving Recommended (ESR) double glazing we could save 850 million from our fuel bills and enough energy to heat over 1 million homes per year. The British Fenestration Rating Council (BRFC) and the Energy Saving Trust (EST) have developed a government backed scheme whereby windows are rated according to their energy efficiency (insulation and heat saving). Windows are rated for their energy using the familiar A G scale applied to white goods such as fridges. Thus an A rated window is considerably more efficient than a G rated window. With double glazing you will experience: Improved Energy Efficiency and Comfort Reduction in Energy Bills Reduce Condensation Increased Security Reduced Noise Transmission The benefits of energy-efficient windows: Smaller energy bills: replacing all single-glazed windows with B-rated double glazing could save you around 165 per year on your energy bills. A smaller carbon footprint: by using less fuel, you will generate less of the carbon dioxide that leads to global warming - typically, 680kg a year. A more comfortable building: energy-efficient glazing reduces heat loss through windows and means fewer draughts and cold spots. Peace and quiet: as well as keeping the heat in, energy efficient-windows insulate your property against outside noise. Reduced condensation: energy-efficient glazing reduces condensation build-up on the inside of windows. The costs and savings for energy-efficient glazing will be different for each building and each window, depending on the size, material and installer. Double glazing should last for 20 years or more. Ventilation Replacement windows will be more airtight than your original frames, so condensation may build up in your house due to the reduced ventilation. If your house does not have much background ventilation, look for replacement windows with trickle vents incorporated into the frame to let in a small amount of controlled ventilation. ALTERNATIVES TO DOUBLE GLAZING If you cannot install double glazing for example if you live in a conservation area, period property, or listed building you can install secondary glazing, use heavy curtains, or do both.

4 Secondary glazing: A secondary pane of glass and frame can be fitted inside the existing window reveal. This will not be as well sealed as a double-glazing unit, but will be much cheaper to fit, and will still save energy - you could save about 100 a year on fuel bills. Low emissivity glass will improve the performance of secondary glazing. Heavy curtains, sealed blinds and shutters: Curtains lined with a layer of heavy material can reduce heat loss from a room through the window at night and cut draughts. Hollow blinds, fitted into place with a sealed frame, and sealed shutters will also help cut draughts and keep your heat in for longer. SOLAR WINDOW FILM Providing an abundance of natural light in your buildings is a great way to conserve energy. But sunlight can create excessive heat and uncomfortable hot spots, fades valuable furnishings, creates computer screen glare and contains harmful UV rays. Whether your buildings are high-rise or low-rise, a Sun Control Window Films can help you to control energy costs and provide tenants with a more comfortable environment. Solar window film In addition to energy savings, solar window film provides many attractive benefits: 1. Maintaining moderated indoor temperatures by significantly rejecting solar heat transmitted through glass and windows 2. Allowing natural day lighting while reducing glare 3. Providing unobstructed enjoyment of scenic views without blinds, shades or shutters 4. Protecting expensive furniture, curtains, artwork, flooring, etc. by blocking over 99% of UV rays 5. Providing added safety and security by protecting against injuries resulting from flying glass due to breakage from severe weather, break-in attempts, or terrorism. Traditional window blinds, curtains and awnings can obscure your view, making the room darker and require regular maintenance. Tinted window film avoids these drawbacks. This product is not expensive, however the installation costs can be high. Payback will vary depending upon the amount of sunlit glass exposure, the type of solar window film, the type of glass, cost of fuel, cost of application, etc. but the range is in the 2-5 year period. ENERGY EFFICIENT DOORS Like any other part of the building, doors can be insulated and draught-proofed to prevent heat from escaping. Buildings regulations state that installing a new door requires approval from the relevant buildings control body, and new external doors now generally contain integrated insulation to reduce heat loss and comply with the regulations. A properly fitted new external door should include an effective draught-proofing system. Existing doors can be improved by fitting draught-proofing strips around the seals and the letterbox. Fitting draught-proofing to the doors and windows could save up to 40 a year.

5 DRAUGHT PROOFING As well as insulating the walls, it is essential to ensure that the building is draught proofed. There are often large gaps under doors and around window frames, which allow draughts in and heat out. Consider fitting or renewing draught excluders to external doors and windows, to reduce heat loss through air infiltration. The addition of wall insulation to the building will remove draughts from poorly maintained brickwork. Other gaps must be blocked individually. This can be achieved using products purchased from DIY stores, and can be quite a simple process. Draught proofing is easy to obtain and fit. Gaps around doors can have rubber seals or brushes fitted. These can be purchased from DIY stores, and simply screwed into place at the edge of the wooden door, or fixed to other materials following the instructions given by the manufacturer. Draught proofing is a vital part of ensuring the efficiency of your heating system. If full draught proofing is achieved, very little heat will be able to escape. However, there should always be some ventilation available in occupied buildings. Always ensure that sufficient ventilation is available, preferably by a well designed mechanical or natural ventilation system. A good rule of thumb is that buildings should be sealed tight and vented right. DRAUGHT LOBBY Heat is lost when doors and windows are opened to the outside. By providing sufficient space for the outer door to be closed before opening the inner door, the draught lobby functions in a similar manner to an air lock. To be specified as a draught lobby, the enclosed space should be at least 2m 2 in floor area, it should open into a circulation area, and the door arrangement should be such that a person with a push-chair or similar is able to close the outer door before opening the inner door. The draught lobby should have a minimum depth of 1.2m and a minimum width of 1.2m. It may be heated or unheated and may provide access to a cloakroom Draught lobby example A further effect of the sunspace is to shelter the envelope from wind chill and rain this factor becomes increasingly important in northerly and exposed locations. By effectively adding another layer to the building envelope, the sunspace becomes a thermal buffer rather in the manner of air within a cavity wall.