So after a fun (?) summer of consultations, the final date for submission for the Part L and F consultation will soon be upon us: 17th September. The consultation came out on 18 June, but with a massive 800 odd pages to wade through it has taken most of the summer to digest.
This series of posts will mainly concentrate on Part L2 for non-domestic buildings, so I won’t touch on the consequential improvements debate. Plenty has already been said on this here, here and here (that last link is where the ACE have threatened to sue the government – oh to be aÂ feisty lobbyist!). For those who are interested in Part L1, there is a good summary over on the NHER website (pdf). There is also a very good CIBSE micro-site available which covers L1 and L2. Comments could be added to the CIBSE response up until 4th September, so too late now. However, it is worth checking out some of the questions and answers on the forum.
There is also a good powerpoint presentation from AECOM/BRE available here (216 slides, 8MB long but useful): www.aecom.com/media/5930.pdf
I shall start with some basics, to set the scene:
The Approved Document (AD) deals with the energy efficiency requirements in the Building Regulations 2000. Historically, the AD was only a method of compliance (not a regulation). This changed in the 2006 revisions to the Building Regulations (which I will touch on below).
It is worth reminding ourselves what Part L of Schedule 1 states:
Where does our carbon obsession come in then? There is only mention of energy and fuel in Part L? This tension between energy and carbon comes up again later, so pay attention.
There are currently two separate requirements to carry out CO2 emission rate calculations. These are under (i) regulation 17C of the Building Regulations 2000 and (ii) Regulation 17E implementing ArticleÂ 7 of the Energy Performance of Buildings Directive, requiring the provision of Energy Performance Certificates. It has been proposed that these two be simplified into one regulation but has not yet happened. The ‘master’ Building Regulations document is available here (pdf). The Schedule comes at the end. So our approved document ADL2A incorporates not just Part L, but regulations 17C and 17E. Confused yet?
The AD sets out 5 criteria. If it can be demonstrated that all five have been met, then the building is compliant. Of these, the first directly relates to a regulation (17C) and is therefore mandatory. The BER must be less than the TER and either SBEM or DSM must be used to demonstrate compliance. Criterion 2 through 5 remain guidance only. The 2010 revisions to 2006 are in italics below, deletions shown in strikeout:
Criterion 1: in accordance with regulation 17C, the calculated predicted CO2 emission rate for the building as constructed (the Building Emission Rate, BER), must not be greater than the Target CO2 Emission Rate (TER)
Criterion 2: the performance of the building fabric and the heating, hot water and fixed lighting systems should achieve reasonable overall standards of energy efficiency following the procedure be no worse than the design limits set out…
Criterion 3: Those parts of demonstrate that the building that are not provided with comfort cooling systems have has appropriate passive control measures to limit solar gains. The guidance given in…; and the aim is to counter excessive internal temperature rise in summer in accommodation that does not need air conditioning and where it is not therefore provided. The impact on CO2 emissions from mechanically cooled buildings is taken into account in the BER. the purpose is to limit solar gains to reasonable levels during the summer period, in order to reduce the need for or installed capacity of air conditioning systems.
Criterion 4: the performance of the building, as built, is consistent with the prediction made in the BER…Extra credits will be given in the TER/DER calculation where builders provide robust evidence of quality assured procedures in the design and construction phases
Criterion 5: the necessary provisions for enabling energy efficient operation of the building should be put in place.
The UK’s much touted zero carbon goal was actually set in the Budget in 2008:
an ambition for all new non-domestic buildings to be zero carbon from 2019 with consultation on the timeline and its feasibility and new public sector buildings from 2018
So now we know where all the regulations and goals come from, the next post will get on to the changes for 2010.