The new Code for Sustainable Homes has finally arrived. Here’s a 10-point summary of the changes and the suggestions that didn’t make it into the final document

Last month, slightly later than anticipated, the updated version of the Code for Sustainable Homes arrived. It has been almost four years since the launch of the government’s tool for making sure all new homes are zero carbon by 2016. In that time, there have been many changes to the regulatory landscape.

We’ve had new versions of the Building Regulations covering energy and ventilation; changes to SAP, the software used to demonstrate that new homes comply with energy requirements; and consultation on the definition of zero carbon. All this has necessitated some tweaks to the code.

Unless your development is being built to the 2006 version of Part L of the Building Regulations, the revised code will apply.

This may be the final update of the Code for Sustainable Homes in its current guise. The coalition government is committed to reducing regulation and is rumoured to be keen to scrap the code. It says plans to review the future role of the code are being considered, alongside a wider rationalisation of housing standards.

Adding weight to this, the housing minister Grant Shapps last month wrote on Twitter that the code would be merged into the Building Regulations. There are plenty of questions over how practical this would be, but don’t rule it out.

What’s changed

One of the main reasons for the revision of the code has been to align it with the changes to Part L and SAP software - in particular to recognise the tougher standards for carbon emissions in the 2010 Part L. This means the minimum mandatory CO2 emissions standards for level one, two and three homes have been dropped as these are now met simply by complying with the Building Regulations. However, a level-four home will still be a 44% improvement on the carbon emissions target of a home built to the 2006 Part L, which equates to a 25% improvement on the 2010 version. A level-five home is a 100% improvement on 2006 Part L, while a level-six home has net zero emissions, as before.

Although the full details of the definition for zero carbon have yet to be published, the minimum fabric energy efficiency standards were published in July. These promote a “fabric first” approach to reducing energy consumption, rather than generating energy through renewables, and have been adopted in the code for levels five and six, replacing the heat loss parameter.

Credits for specifying low-energy lighting have been dropped from the code because the incentive for this is covered by Part L. Instead, credits are now offered for energy display devices. Those that display both electricity and primary heating fuel consumption will qualify for maximum credits. The specification of the devices is based on the outline in the Department of Energy’s consultation for smart meters.

The housing minister tweeted that the code would be merged with the building regs. there are plenty of questions over how practical this would be

Under the code, the lifetime homes standard, which helps future-proof designs to meet the needs of ageing residents, is mandatory for level six. However, steeply sloping plots will be exempt from the standard, an acknowledgement of the physical difficulty of getting some sites to comply with the requirements. In reality, few developments will be affected but those that are will not be able to market themselves as achieving the lifetime homes standard. There was also a proposal to make the standard compulsory for level-four and level-five homes, but this has not been adopted.

Mandatory site waste management plans have been dropped from the new edition of the code because this is now a legal requirement. There are still credits available for those who go beyond the minimum regulatory obligations, however.

In the energy sections of the code, a sliding credit scale has been introduced, based on steps of 0.1 credits. As well as being more sensitive to incremental performance improvements, it will reduce the likelihood of developers downgrading specifications where performance is above a benchmark but is not rewarded with additional credits.

What was proposed but not included

It had been hoped that full details of the zero carbon definition being drawn up by the communities department would have been available before the updated code. As it was not, plans to integrate lower levels of carbon compliance and allowable solutions (using off-site measures to offset carbon emissions ) for levels five and six have been put on hold. The new definition could be added to the code as soon as it is published, but this is not expected until next year.

The consultation on the revision also asked whether a lower fabric efficiency standard for level-four homes should be introduced, to start bringing the code into line with the definition of zero carbon before 2016. This has been dropped. Instead, guidance will be provided on what level should be achieved for those building to level four in anticipation of 2013 when the Building Regulations are set to match level-four energy requirements.

Credits are now offered for energy display devices. those that show both electricity and primary heating fuel consumption will get maximum credits

A proposal to double the external space for waste storage to accommodate fortnightly collections has been abandoned. So has the suggested requirement for mobility equipment storage instead of cycle storage in specialist accommodation such as retirement homes. Proposals to reduce home office space for specialist housing or retirement homes have also been dropped.

A plan to change the way credits are allocated for security has been shelved, although cycle storage must be to Secured by Design standards. A wider review of security in building standards will be conducted in the coming months.