and Local Government (DCLG) recently said at a housing conference that DCLG now expects the cost of allowable solutions per dwelling to be around £1,000. This figure came as quite a surprise as it also means that DCLG are expecting the cost of carbon for delivering allowable solutions to be lower than those set out by DCLG in the terms of reference of the Hub task group. It’s true that this new definition of
‘zero carbon’ has not changed the carbon compliance levels that developers have to meet on site; the standards still involve an improved building fabric specification and a certain amount of renewable energy (or moving towards a Passivhaus specification without any renewables). But there is undoubtedly a big change in terms of how far developers have to go to offset non- carbon compliance emissions on site or through allowable solutions. Even under the original definition it could
have been argued that a dwelling would actually be ‘carbon neutral’ rather than ‘zero carbon’. As a result of the changes, homes will at best be only ‘low carbon’. The new definition of zero carbon is a bit like taking a return flight in a new, efficient aeroplane, offsetting your emissions at the airport but only offsetting one leg of the journey and arguing that the plane would have been coming back anyway!
around half of the emissions of a typical new home – out of the scope of the definition. By changing the definition from a dwelling
that is at Code Level 6 to one that is now effectively at Level 5, the government has more than halved the amount of carbon to be offset by allowable solutions; which means it has, at the very least, halved the funding that will be available to do ‘other works’, such as offsite wind power and local district heating. The Hub’s report estimated the cost of allowable solutions for a Code 6 home to be about £5,000 per dwelling for the full (Level 6) definition. With a Level 5 dwelling (which is what we have under the new definition), you would expect this to drop to around £2,500, hence a halving of funding for the kind of works described above. However, Richard McCarthy, director
general at the Department for Communities
www.cibsejournal.com
An example of a house built to Level 6 of the Code for Sustainable Homes – a level considered to be truly ‘zero carbon’
Pragmatic It is true that the new definition of ‘zero carbon’ is seen by many in the industry as a sensible, pragmatic change, making it easier for developers to build more low carbon homes than they might have done under the original definition – and more homes are desperately needed. There is also the argument that, in a few decades’ time, when the grid is more fully decarbonised, then these homes could in effect become zero carbon. There are, indeed, many pros and cons surrounding this decision. One concern is that the change will have an impact on the ability of new housing developments to cross-subsidise or part-fund other works, including, for example, community heating schemes. This reduction in funding will hit local authority programmes such as the upgrading of district heating systems and the retrofitting of existing dwellings. Another concern raised by consumer groups is that there is a potential for people
July 2011 CIBSE Journal 39
Barratt
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68