Code for Sustainable Homes
What is the Code for Sustainable Homes?
The Code for Sustainable Homes (CSH) is a form of environmental assessment applicable to new build residential projects. It assesses the building on a number of environmental factors. The building is scored against each principle with an overall level between 1 and 6 given at the end of the assessment.
Who needs a Code for Sustainable Homes?
The Code for Sustainable Homes is now a council’s minimum requirement for new build project or major refurbishments. It often used as a marketing tool as even a Level 1 rating shows a significant improvement over and above Building Control minimum environmental requirements.
Overall the Code for Sustainable Homes offers a standout badge of environmental stability both in the way a house has been constructed and its ongoing environmental impact.
Other Code rated developments are driven by legislation as all publicly funded residential developments much reach Code Level 3.
Why choose EAL to help me with the Code for Sustainable Homes?
EAL have experience of producing of Code assessments for a range of clients. We know that our clients want each site to be assessed on its own individual merits and with no generic advice given, so this is the service that we provide.
A specific assessor is allocated to each case and will be your single point of contact for all technical matters throughout the construction process. This way the assessor gets to understand the case and your construction methods in great detail.
The Code can be a complicated process, one which our experienced assessors and tested methodologies can help you to navigate with the minimum of fuss.
The minimum energy efficiency requirements and how they can be achieved are found in Part L of the Building Regulations These latest revision of Part L came into effect in 2006 and subsequent revisions, the latest being in 2010.
The Code for Sustainable Homes Standard
Figure 1 sets out, with respect to carbon emissions, the improvements over the 2006 standards that were revised in 2010, and will be revised again in 2013 and 2016.
These equate to the energy performance standards in the Code for Sustainable Homes Levels 3, 4 and 6 respectively.
(base = 2006 standard)
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Figure 1: Percentage reduction in target carbon emissions (TER) required by each standard |
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Until 2013 the standard is likely to continue to be set with reference to those sources of emission (space, water heating and lighting) that are contained in the 2006 regulations and to offer the option of adopting Low and Zero Carbon (LZC) technologies. The step to zero carbon in 2016 is likely to include emissions from other sources (principally electrical appliances), which would result in the need for significant renewable generation capacity as well as other LZC systems.
Who requires a SAP or SBEM calculation?
The way its currently working in the field, is anyone who is involved in a development that requires a change of use, or an extension of more then 25% of the size of the building or with glazing of more than 25% of the extension, will require SAP calculations to be carried out on the carbon footprint of the building and in the case of commercial buildings, SBEM calculations. Once these calculations are carried they will know whether their development reaches the required target.
There’s been a steep learning curve for everyone, including building control officers who are very often unsure of what’s required. This may sound odd, but is particularly true when it come to older building with extensions.
What is BREEAM?
BREEAM Codes cover all new build domestic and commercial buildings. The Code for Sustainable Homes for new domestic dwellings is an environmental assessment rating and is used as a design tool to measure and improve the specification for the construction of environmentally friendly homes.
How is a home assessed?
Essentially, it is a two stage process at design and post construction stage to assess the homes on nine different categories of environmental issues:
The Nine Categories:
Energy and CO2 Emissions
Pollution
Water
Health and Wellbeing
Materials
Management
Surface Water Run-off
Ecology
Waste
Each category includes a number of environmental issues and each is assessed for credits.
The table 1: shows the credits available and weighting factors
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Categories of Environments Impact |
Total Credits in each category |
(% Point contribution) |
|
Category 1: Energy and CO2 Emissions |
31 |
36.4 |
|
Category 2: Water |
6 |
9.0 |
|
Category 3: Materials |
24 |
7.2 |
|
Category 4: Surface Water Run off |
4 |
2.2 |
|
Category 5: Waste |
8 |
6.4 |
|
Category 6: Pollution |
4 |
2.8 |
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Category 7: Health and Well being |
12 |
14 |
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Category 8: Management |
9 |
12 |
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Category 9: Ecology
|
9 Total 100 |
12 |
|
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|
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There are three mandatory issues and the target performance in these issues has to be met, before the Code level can be assessed.
What are the mandatory issues needed to meet the Code for Sustainable Homes?
The three mandatory issues are:
- Environmental impact of materials.
- Management of surface water runoff from developments.
- Storage of non recyclable waste and recyclable household waste.
Once the mandatory minimum performance standard is met for the three uncredited issues, four further mandatory issues need to be considered.
The two issues with increasing mandatory minimum standards are:
- Dwelling Emission rate
- Indoor water use
Table 2: Dwelling Emission Rate
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Code Levels for Mandatory minimum standards in CO2 emission |
|
|
Code Level |
Minimum Percentage Improvement in Dwelling Emission Rate over Target Emission Rate |
|
Level 1 (*) |
0% ( Compliance with Part L 2010 is only required |
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Level 2 (**) |
0% ( Compliance with Part L 2010 is only required |
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Level 3 (***) |
0% ( Compliance with Part L 2010 is only required |
|
Level 4 (****) |
25% |
|
Level 5 (*****) |
100% |
|
Level 6 (******) |
Net Zero CO2 Emissions |
Table 3: Indoor Water Consumption
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Code Levels for Mandatory Maximum Standards in Indoor Water Consumption
|
|
|
Code Level |
Maximum Indoor Water Consumption in litres per person per Day |
|
Level 1 (*) |
120 |
|
Level 2 (**) |
120 |
|
Level 3 (***) |
105 |
|
Level 4 (****) |
105 |
|
Level 5 (*****) |
80 |
|
Level 6 (******) |
80 |
The final two issues with mandatory requirements are Fabric Energy Efficiency and Lifetime Homes.
What is Fabric Energy Efficiency?
Fabric Energy Efficiency is the energy demand for space heating and cooling expressed in KWh of energy demand per square metre per year.
What is Lifetime Homes?
Lifetime Homes is only for achieving Level 6 CSH and is basically to promote the construction of homes that are accessible and easily adaptable to meet the changing needs of current and future occupants.
How is a Home rated in the Code for Sustainable Homes?
The rating a home receives depends on how it measures up in the nine categories:
The Code uses a 1 to 6 star rating system to communicate the overall sustainability performance of a new home. A home assessed as 6 stars will have achieved the highest sustainability rating.
The table 4: Relationship between total percentage points score and code level.
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Total percentage Points Score (equal to or greater than) |
Code Levels |
|
36 Points |
Level 1 (*)
|
|
48 Points |
Level 2 (**)
|
|
57Points |
Level 3 (***)
|
|
68Points |
Level 4 (****)
|
|
84 Points |
Level 5 (*****)
|
|
90 Points |
Level 6 (******)
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The results of the Code assessment are then recorded on a certificate assigned to the dwelling.
Who can carry out an assessment for a Code for Sustainable Homes?
A Code assessment can only be carried out by a licensed and accredited Code assessor. This ensures the rating is independent and trustworthy