The hierarchy beginning with energy efficiency up to allowable solutions is still the underpinning of thinking as is the understanding of the need to address the existing building stock.
The time line is challenging - the Zero Carbon Hub and AECOM are working on proposals for dwellings and non-dwellings respectively. There will be working groups set up to meet twice between now and July that will address Dwellings, Non-dwellings, Retrofit with The green deal (joint with DECC) and Compliance with performance. The findings will go to the Building Regulations Advisory Committee (BRAC) in July and it is hoped to produce a consultation document for Ministers to consider between in October and December. The consultation will be carried out in Spring 2012 with the aim of publishing the new Approved Document in October 2012 coming into force in April 2013.
The work already underway is looking at whole life costs and there is considerable concern about how to close the gap between design predictions and performance in use. Some of the current thinking in non-dwellings is to increase airtightness targets to 3 m3/m2/hr @50 pa (as little cost involved); lighting to 75 lumens/W (fewer fittings but what about uniformity?); and to move U values below 2.0 W.m2/k would be very expensive relative to the benefits.
The thinking on dwellings includes a flat versus aggregate approach recognising differing house types will have different energy signatures; moving to an interim Fabric Energy Efficiency Standard (FEES) specification that includes airtightness moving towards 5 m3/m2/hr @50 pa and updating SAP.
DCLG has challenging aims to achieve in terms of the Climate Change Act aspiring to 80% cuts in emissions by 2050 - of course, something like 70% of buildings in 2050 already exist. Not surprisingly, DCLG is looking to industry to help them get the best fit.
BSRIA will be invited to take part in some of the Working Groups so for any input members may wish to make, please contact Mike Smith, 01344 465564, firstname.lastname@example.org.
BSRIA provides airtightness testing and consultancy as well as life cycle costing consultancy, training and guidance. Contact BSRIA on:
T: 01344 465600