THE CODE FOR SUSTAINABLE HOMES (CSH) IS THE NEW STANDARD FOR THE DESIGN AND CONSTRUCTION OF DWELLINGS. IT WAS LAUNCHED BY COMMUNITIES SECRETARY RUTH KELLY ON 13TH DECEMBER 2006, THE TECHNICAL GUIDANCE BEING PUBLISHED IN OCTOBER 2007. THE DIFFERENCE IN THESE TWO DATES PERHAPS ILLUSTRATES SOME OF THE PROBLEMS SURROUNDING THIS NEW STANDARD.
The Code
CSH goes a good deal further than just energy efficiency. It deals with everything related to the construction of the house, the land it stands on and the way it is lived in. It deals with these issues in 9 separate categories:
Energy and CO2 emissions – one of the 3 categories imposing minimum standards at even the lowest level. The category deals with the obvious; efficient boilers, heat loss etc, but also deal with lighting, cycle storage and clothes drying areas.
Water – Sets minimum standards for the consumption of drinking water and provisions for rainwater.
Materials – Deals with the environmental impact of materials and encourages responsible sourcing.
Surface Water Run-off – Specific provisions aimed at reducing flood risk. A critical issue when we consider 3 million new homes to be built
by 2020.
Waste – Looks at both household and construction waste and encourages recycling and responsible construction practices.
Pollution – Deals with emissions from boilers and other heating appliances and encourages the use of sustainable insulation and non-polluting building practices.
Heath and Wellbeing – Ensuring the provision of daylight, views of the sky, adequate gardens, as well as access and adaptability – this broadens into the Government’s Lifetime Homes initiative.
Management – Beyond a “user manual” for the home, it also deals with the management of the construction project and the physical security of the home (bit of a mixed bag).
Ecology – Dealing with the ecological value of the site (encouraging the use of brownfield) and the enhancement of that value.
The Code differs from EcoHomes in several regards. It is assessed at the level of an individual ‘Dwelling’ rather than as a development, which has particular implications in terms of renewable energy generation and the ecology; it sets minimum mandatory standards for energy, water, materials, waste and surface water run-off, which must be met before even the lowest level of the Code can be achieved and which ratchet up as the star rating increases; and it is assessed in two stages with Code Certification taking place after a Post Construction Review has been carried out. – with the obvious potential for necessitating remedial work.
Key Issues for the Builder or Developer
Much of the CSH concerns itself with fairly routine matters but there are 4 key issues that the developer needs to be aware of.
Energy and CO2 emissions – the Government has set a target that all new homes in England will have net zero CO2 emissions form 2016 (2012 in Wales).
The significance of this increases with the desired target star rating. BRE’s Off-Site exhibition has 6 low-energy houses on show, only 1 of which achieves zero carbon. We know that at least 2 others tried for 6 Star and failed. Given that these houses were designed and built by companies like Stewart Milne, Kingspan and Hanson it is an indication of how hard the standard is to reach.
The Government has also recently announced that grid electricity from a green source, e.g. an off-shore wind farm, no longer qualifies as zero carbon unless the development is directly linked to the source, i.e. not grid linked. This means that to achieve level 3 or over will need on-site renewable energy generation. At level 3, solar thermal panels are likely to be enough but beyond that electricity generation becomes a necessity and developers will need to think about wind turbines or solar PV. Which calls into question the whole idea of developing urban brownfield sites.
Water use – The average UK citizen uses 150 litres of water per day. The Code looks to reduce this to below 80 litres. Of course this means lowflush toilets and low-flow showers, but to get beyond level 4 means using less than 90 litres per person and that can only be achieved by introducing alternative water sources, i.e. rainwater harvesting and/or grey water recycling. Low-flush toilets may add a few pounds to the build cost but adding a rainwater harvesting system will add a couple of thousand.
Materials and Waste – The argument behind this is that some 80% of materials used in a conventional build are virgin materials and about 12% of that material goes straight to landfill, without ever being used. Sustainable materials – FSC timber, sustainable insulation, timber windows and doors, add cost to the build, but recycling material and using recycled materials can help to balance this. The DTI, with the co-operation of 2 major developers, carried out some tests in 2005/06 and found that sorting waste and reusing material cut the project cost by up to 8%. The extra costs and/or savings in this category is one area more readily controlled and managed by the developer.
Minimising ecological impact – 12% of the overall points score under the Code are available for the Ecology category. Only Health & Well Being and Energy categories have more points available. Put simply, to gain a good score the Code requires that the site have an initial low ecological value and that the development improve that value by encouraging more species of flora and fauna. In a typical housing development, where space is often at a premium, this can be difficult. There is no minimum mandatory standard here, but it is difficult to get to level 4 and beyond without a good score in this category. It will be necessary to invest in an Ecologist, in appropriate protection to existing features (trees, hedges, ponds, streams, etc) and in new ecological planting and features.
What will it Cost?
As of January 2008, the BRE had still to decide what the costs to the developer are likely to be. From experience with EcoHomes it is known that even a 1 Star rating will have a cost in terms of the fees paid to BRE and the assessor. A 4 star rating or above will involve renewable energy and rainwater harvesting, as well as sustainable materials, top quality site management and fees for a qualified Ecologist and a CSH Assessor. The cost per property will vary with the number of dwellings on the site and with the number of property types as well as the star rating being aimed at. The developer will need to go through a process of quantifying and costing the proposed development against the Code and balancing the cost against the desired star rating.
Is it a Good Idea?
Currently, the energy used to heat, light and run our homes accounts for 27% of all of the UK's carbon emissions - around 40 million tonnes per year. Energy efficient and insulated buildings, which draw their energy from zero or low carbon technologies will help but they are not the end of the story. A conventionally built 3 to 4 bedroom house has embodied in it some 44 tonnes of CO2 . The Code seeks to reduce the emissions from every house, but also to reduce the energy embodied in each house. They are also aimed at extending the life of the house from the current 60 years to 80 years plus.
It may be that climate change is no more than scare-mongering and that this is all unnecessary. In which case we end up with houses that will last longer, are cheaper to run and set in more pleasant surroundings. If climate change is real and we do nothing the outcome is catastrophic. The Code is difficult; it sets hard targets, changes the way we build houses, makes us think about the methods and materials we use. With oil at over $100 a barrel it is difficult to see how that can be a bad thing.
CSH forms part of a package of measures aimed at moving us towards the zero carbon target set by the Government for all new buildings from 2016. It is based on the EcoHomes standard and replaced EcoHomes for new homes in England from 1st April 2007 (EcoHomes will continue to be used in Wales and for renovation projects in England and Wales). BRE are planning to run CSH as a separate fully functional scheme from spring 2008, with a network of Licensed Assessors ready to provide Code certification. As of January 2008 they had not arrived at a fee for the certification, again pointing at the difficulties surrounding this scheme.
Assessment under the Code is voluntary, at least until April 2008, unless it is a Housing Corporation or English Partnerships development or similar. CSH has six levels or star ratings, with Level 1 requiring thermal efficiency just above Part L 2006; level three being 25% improvement on Part L, and level six being 'zero carbon.'
