Monday, 23 January 2012

So what is the ‘Code for Sustainable Homes’ ?

 The Code for Sustainable Homes is an environmental impact rating system for housing in England and Wales, setting new standards for energy efficiency and sustainability which represent important developments towards limiting the environmental impact of housing. The Code was officially launched on 13 December 2006, and was introduced as a voluntary standard in England in 2007. It complements the system of Energy Performance Certificate for new homes introduced in 2008 under the European Energy Performance of Buildings Directive, and builds on the most recent changes to Building Regulations in England and Wales. The code works by awarding new homes a rating from Level 1 to Level 6, based on their performance against 9 sustainability criteria which are combined to assess the overall environmental impact. Level 1 is entry level above building regulations, and Level six is the highest, reflecting exemplary developments in terms of sustainability.

The sustainability criteria by which new homes are measured are:
   •    Energy and CO2 Emissions – Operational Energy and resulting emissions of carbon
        dioxide to the atmosphere (both of which have minimum standards that must be met at
        each level of the code)

   •    Water H2O & Surface Water Run-off – The change in surface water run-off patterns as a
         result of the development– The consumption of potable water from the public supply
         systems or other ground water resources (each of which have minimum standards to be
         met  at entry level)

   •    Materials – The environmental impact of construction materials for key construction
        elements (no mandatory minimum standards).

   •    Surface Water Run-off - Management of surface water run-off from the development and
         flood risk

   •    Waste – Waste generated as a result of the construction process and facilities
        encouraging  recycling of domestic waste in the home (no mandatory minimum

   •    Pollution – Pollution resulting from the operation of the dwelling
        (no mandatory minimum  standards).
   •    Health and Well-Being – The effects that the dwelling’s design and indoor environment
         has on its  occupants (no mandatory minimum standards).

   •    Management – Steps that have been taken to allow good management of the
        environmental impacts of  the construction and operation of the home
        (no mandatory minimum standards).

   •    Ecology – The impact of the dwelling on the local ecosystem, bio-diversity and land use
        (no mandatory minimum standards).

   In March 2008, the UK government announced a mandatory requirement for all new homes to be rated against the Code commencing May that year. No specific star ratings or assessments were set, but the rating meant that every new home owner knew whether their home was built to higher standards than building regulations and what standards had been met.

   In 2010 Code level 3 compliance became mandatory for public and private sector new-build residences, including flats and houses, effectively making redundant the use of code levels 1 & 2. Currently, compliance with higher levels of the Code is voluntary, with a long-term view for step-change increases. However, by making the information routinely available consumers are encouraged to be more demanding whilst also serving as an incentive for developers to consider building to the Code’s higher standards.

   Technical guidance is amended on a six-monthly basis, every April and October to reflect changes in materials and building techniques resulting from feedback from assessors and industry. There are also changes in the figures used relative to Approved Document Part L1A of the building regulations, for example the thermal standards set in Part L October 2010 make redundant the thermal standards of the Code for Sustainable Homes levels 1-3. This is representative of the Building Regulation's gradual improvement of thermal standards, level 4 Code thermal standards are set be part of the Building Regulations by 2013.

   The extra-over cost of building to Code Level 3, based on a building with a footprint of 100m² is valued between around £10,000-16,000, additionally the Code assessment costs around £2000 for a typical residential dwelling, the total cost of this is typically under 12% of a standard build. This includes such items as rainwater harvesting, solar thermal panels for hot water and electric. It should be understood that whilst the cost of developing to Code 3 and higher standards incurs the initial extra costs, substantial savings will be made in terms of the running costs, and importantly reduce the environmental impact both during construction and over the life of the building.