Page 68

Building Products December 2017

RENEWABLES AND ENERGY EFFICIENCY FABRIC FIRST When taking a whole house approach, it is important to get the fabric right before going down the renewables route, according to Simon Storer, chief executive of the Insulation Manufacturers Association (IMA). Whether building a new or renovating an existing home to achieve higher levels of energy efficiency, getting the fabric right is the first and most important consideration as the basis of any design. A well-designed and insulated building fabric not only provides the benefits of energy reduction and better control of internal temperatures, it will keep the occupants warm in winter and cool in summer, adding to their thermal comfort and wellbeing. The thermal performance of the building envelope makes a significant contribution to reducing heat loss, improving energy consumption and cutting carbon emissions, which for the consumer means lower energy bills. Having energy efficient materials integrated into a building means occupants are required to do less to operate their energy efficient building. Fabric first is essentially a ‘fit and forget’ option that homeowners or occupiers will appreciate without even realising it. With little or no maintenance, energy efficiency is built into the building fabric for the life of the building. By reducing the total energy envelope of a building, the size and capacity of any renewables can be reduced, which, in turn, will reduce capital costs, running costs and even auxiliary equipment such as heat emitters, thermal and electric storage. A fabric first approach is considered by many to be more sustainable than installing energy saving 68 BUILDING PRODUCTS | DECEMBER 2017 technology or renewables at a later date which can be expensive and may not be used efficiently by the consumer. Compared to renewable technologies, fabric measures require little or no maintenance (excepting windows and some retrofit insulation), and offer a considerably longer lifespan (to match the life of the dwelling). Many renewable technologies have a realistic lifespan of around 20 to 25 years, if adequately commissioned and correctly and regularly maintained. Some technologies such as inverters will require part replacements over that period to maintain efficiencies. Tighter fabric targets Buildings should be at the heart of energy policy with the fabric first approach to energy efficiency ensuring that a thermally insulated building envelope delivers high performance, low maintenance, reduced energy bills and long-term energy efficiency. The Standard Assessment Procedure (SAP) is the methodology used by the government to assess and compare the energy and environmental performance of dwellings. Its purpose is to provide accurate and reliable assessments of dwelling energy performances that are needed to underpin energy and environmental policy initiatives. Within the SAP, there are two targets – one is an overall CO2 target and the other is a Fabric Energy Efficiency Standard (FEES). This sets a separate target for the building fabric and means that design must take a whole house approach and ensure a good performing fabric so compliance cannot rely on the addition of renewables without taking a fabric first approach. Insisting on tighter fabric targets is essential if we are to reduce heat demand, lower our fuel costs and reduce emissions. Once good building fabric has been built, there is no need to worry about it. Fabric first will enable developers to future proof their designs which can then be employed on projects of any size; from the largest public building, to the smallest domestic extension. A more energy efficient fabric from the outset can be upgraded down the line through improved services, ventilation measures or the addition of renewable technologies. While insulation clearly has the biggest role to play in improving the thermal performance of a building, fabric first is about giving consideration to ensuring continuous insulation, minimising thermal bridging, and achieving high levels of airtightness. Addressing these aspects of construction means the Building Regulation’s thermal targets can be met and those performance levels can be translated to the finished building. It also means the building will do the work before you consider the add-ons. insulationmanufacturers.org.uk


Building Products December 2017
To see the actual publication please follow the link above