The UK Government states that social housing should meet a minimum standard of decency. A decent home is described as one that; doesn’t contain any health and safety hazards, is in a decent state of repair, has reasonably modern facilities and provides reasonable thermal comfort and is well insulated.
The English Housing Survey released by the Department for Communities and Local Government (DCLG) in 2015 suggests that 21% of social housing failed to meet the decent homes standard in 2013. Of these, 72% failed due to being energy inefficient.
Furthermore, the Office for National Statistics reports that there were 18,200 excess winter deaths in England and Wales in 2013/2014. It also states that there were 11.6% more deaths in winter months compared with the non-winter months in the same period. Cold homes are a major contributor to these deaths as a reported one in five people live in fuel poverty.
As 70% of currently inefficient housing stock will still be in use in 2050, cost-effective, large-scale sustainable refurbishment will be a necessary part of improving the housing stock across the country. Changes such as installing energy efficient windows and doors can help towards the creation of homes with enhanced thermal ratings, providing tenants with warmer properties and reduced energy costs.
Furthermore, clear, reliable information about the energy performance of a dwelling is a crucial first step in market transformation.
In 2007 the government introduced Energy Performance Certificates (EPC) to tackle the problem of Britain’s large stock of inefficient housing. An EPC is used to calculate the energy performance of buildings, providing prospective tenants and occupiers with information relating to a property’s energy use and carbon emissions so they can consider its thermal levels and fuel costs.
It is the joint responsibility of landlords, builders and installers to ensure that Energy Performance Certificates are up to date and available to tenants whenever any improvement work such as loft and wall insulation, new boilers installation or windows and doors upgrade takes place. Last year, 2,232,991 EPCs were logged on the Domestic Register with 11% receiving an A or B rating, 53% getting a C or D with the remaining 36% rated E, F or G. Properties with an A or B rating exceed current standards whereas properties rated D-G are the worst performing. However, from 1st April 2018 landlords will be forced by new energy efficiency regulations to upgrade the energy efficiency of hundreds of thousands of homes currently rated F and G to a minimum of E or face being unable to let them until they improve the rating.
When making decisions on moving home, tenants can use EPCs to compare the energy efficiency of similar properties. For landlords, an EPC provides a recommendation report that lists cost-effective and other measures to improve the building’s energy rating.
As approximately 20% of the heat lost in a home is through its windows and doors, energy efficient window and door systems can help cut a building’s carbon emissions and reduce its energy demands, lowering heating costs while keeping occupants warm and comfortable.
Approved Document L1B of the Building Regulations (England) requires window and door systems to have either minimum U-values of 1.6 W/M²K for windows and 1.8W/M²K for doors, or a ‘C’ level or above Window Energy Rating (WER) and Door Energy Rating (DER).
Fabricators and installers are responsible for ensuring that the windows and doors they supply or install in retrofit and refurbishment projects meet the minimum U-value for windows and doors. The U-value is a very useful measure of window and door energy ratings as it provides efficiency details relating to heat loss by calculating the amount of heat lost in watts per square metre when the temperature outside is at least one degree lower.
In addition, the most energy efficient window and door systems are thermally broken, meaning that there is a barrier between the inner and outer frames to prevent temperature transfer through the frame and condensation on the inner frame. Thermally efficient systems should provide lower U-values, equating to a better protected property.
Window Energy Rating (WER) and Door Energy Rating (DER) measure the thermal efficiency of a standardised complete fabricated system to produce an energy performance level. Introduced by the British Fenestration Ratings Council, the ratings range from A-G with ‘A’ being the most energy efficient. In addition to thermal insulation (as measured by the U-value), WERs and DERs also consider air tightness to ensure systems do not lose heat from their weather seals and glazing seals. The ratings also take into account the positive heating effect (or solar gain) as a result of more glass and less frame, which can reduce the need for heating on colder days. Slim sightlines also provide an opportunity for increased external light transmission into the property.
Shakespeare House in Hackney, London is an example of a social housing redevelopment project that meets definite energy targets to achieve level 4 of the Code for Sustainable Homes.
Islington and Shoreditch Housing Association (ISHA) worked with bptw partnership to reconfigure the existing housing block, installing additional windows to increase the amount of natural light and completely insulate the building to improve thermal efficiency. The project saw the existing 24 flats converted into 18 high quality modern apartments, enhancing each property’s amenity space, living area, kitchen and bathroom space.
The architects specified aluminium window and door systems from AluK to meet their target of a 1.5 U-value using AluK’s 58BW window systems, 58BD and GT55NI door systems for all the existing floors and new elevation from ground to fifth floor level. The 58BW window and 58BD door systems offer a narrow profile solution with a unique polyamide thermal break design to improve thermal performance. In addition, the 58BW and GT55NI systems met the security requirements defined by ISHA as they are certified under the Secured by Design scheme.
The products also integrated well with project’s design and aesthetical elements, achieving the aspired deep reveal effect that was proposed at the planning stage. The deep reveals and window surrounds, new doors, as well as cladding, create a strong architectural feature and define the whole development, presenting it in a completely new light.