Delivering Low Energy Buildings for Real - 66
This Guide is a unique publication which combines professional guidance from a range of suppliers and industry experts, which, when combined together, can deliver a low energy building. A variety of systems are presented ranging from ventilation systems to a range of insulation, airtightness, windows and water treatment systems. In order to ensure these systems perform to their optimum efficiency & to minimise unforeseen additional costs in the construction process; it is essential that each of these systems are installed by adequately trained personnel. Moreover, to ensure a building truly performs to its optimum efficiency; each profession who interacts with the building envelope, be it a plasterer, plumber or electrician, must recognises the importance of continuity of the thermal insulation and airtightness layer of the building. A series of independent studies in the UK (LowCarb4Real; 2009) highlighted a performance gap between what were thought to be low energy buildings, to what in reality were much lower performing than expected. This was also highlighted in the Republic of Ireland by an SEAI report which highlighted that less than a third of new homes meet the energy efficiency and carbon emissions regulations (Passive House Plus 2013). Unfortunately, there is a clear performance gap in many buildings, from what was thought to be low energy, to what in reality consumes much more energy.
More demanding building regulations not only require an improvement in individual skills, but require a change in attitude to working collectively with a focussed cooperative approach to achieve compliance with regulations. Figure 1 presents an example of good site control and communication between trades on a Passivhaus under construction in Dublin.
Figure 1: An airtightness quality control station on site in Dublin, 2013
Changes in building standards directly affect onsite practices collectively and require a focused cooperative approach to achieve compliance with regulations.
The production of truly low energy buildings require diligent attention to detail and cooperation between all trades involved in the construction and renovation processes. All trades should view the house as a system, rather than the sum of its parts. Trades must work as a team. All works must be coordinated.
The current fractured approach to building must be changed to a systems approach to building, in a similar manner to Passivhaus building principles and the quality standards, which are often observed on low energy or Passivhaus projects in Ireland, the UK and Germany. From the design stage planning and simplifying details is essential. Having “toolbox talks” at an early stage of the build process with key personnel who interact with the thermal envelope of the building is essential to minimise costly errors, conflict and poor building performance.
Figure 2: Airtightness & Insulation Training at Ecological Building Systems
Many material suppliers now provide training for designers and builders for their products. The House Planning Help website (http://www.houseplanninghelp.com/ ) is also a useful resource for those seeking more information with regards to the management and delivery of truly low energy buildings.
A range of training courses are also been developed by the government, such as the Qualibuild training programme (www.Qualibuild.ie).
It is not only important to ensure appropriate materials and systems are utilised in low energy building, but to ensure they are installed correctly in conjunction with all other trades on site, and planned from the outset to deliver truly low energy construction.
By Niall Crosson, Technical Engineer, BTech,MEngSc,MIEI, CEPHC
Ecological Building Systems