A low carbon Building Standards strategy for Scotland (the Sullivan report): 2013 update

Process - Delivering a 'net zero carbon' standard for new development

We acknowledge that delivery of zero carbon objectives through an entirely on-site strategy is not currently a realistic approach for mainstream housing production, due to issues of cost and practicality of building to such a standard on many sites. This follows work, by the Zero Carbon Hub ^[4] ( ZCH), into practical means of delivering zero carbon new homes. We consider that this premise is likely to apply equally to new non-domestic development.

During discussions, we noted that the UK definition of 'zero carbon building' was amended in 2011 to remove the energy element relating to cooking, appliances/ equipment and process ^[5] , bringing it into line with the definition of 'net zero carbon' put forward in our 2007 Report.

One outcome of the ZCH review was development of the concept of 'Allowable Solutions' ^[6] . This could offer flexibility in meeting a regulated emissions standard by looking beyond the development site itself. It was first raised in 2008 and discussed in detail in publications by the ZCH from 2011. The Panel noted that this concept was to be further investigated by the UK Government this summer ^[7] .

We recognise that the cost of delivering a 'net zero carbon' building can vary considerably, as can the practicality and risks of applying certain solutions, including low and zero carbon technologies. We endorse the view that setting a 'net zero carbon' standard purely on the basis of on or near-site solutions is not practical at this time. Should Scottish Ministers seek to deliver a 'net zero carbon' policy for new development, it is felt that greater flexibility in how such a standard is delivered is essential.

Whilst the focus of current ZCH work is on domestic construction, we noted that the concept of 'Allowable Solutions' should also apply to new non-domestic buildings.

We support further investigation of the potential for 'Allowable Solutions' to address the gap between levels of carbon compliance set by building or site-related measures and a 'net zero carbon' standard. We understand that this would require amendment to primary legislation but that this does not hinder initial investigations.

In taking this forward, we consider the following to be of importance:

• 'Allowable Solutions' should apply in addition to a minimum level of building performance set through energy standards.
• Provide clear information on what constitutes an 'Allowable Solution', with a range of options to allow flexibility in approach but avoiding over-complexity.
• They should be simple to implement and offer benefits which are easily substantiated and are additional to those delivered by other initiatives or incentives.
• Prior to implementation, establish the delivery processes and tools which enable demonstration of benefit, to support certainty in application by developers.
• 'Allowable Solutions' may be perceived as a 'carbon tax' on new development. The application of such a mechanism at a national level will require significant discussion and engagement in developing proposals.

We noted that there may be a range of presentational issues around the concept of 'Allowable Solutions', including that they may not directly benefit the owners or occupiers of new buildings. Also that the concept of 'saving carbon' is not as familiar a concept as 'saving energy' which equates to 'saving money'.

In taking forward the standards set for building-related measures, our general view is that development should focus on reducing energy demand through a 'fabric first' approach, with efficient services, supported by use of renewable technologies, where appropriate. This is particularly relevant for new homes. We also strongly advocate use of simple solutions rather than 'layering' of complex technologies.

We discussed how, in contributing to emissions reduction, 'Allowable Solutions' as a policy may only be effective in the medium term. This is due to broader agendas such as grid decarbonisation, locally distributed heat, and other work to improve the energy efficiency of the existing building stock. It is important this be borne in mind.

Finally, we consider that, should a 'net zero carbon' standard be delivered through 'Allowable Solutions', terminology must be clear and representative of what is being sought. In particular, it should be explicit that very low carbon buildings implementing 'Allowable Solutions' can meet a 'zero carbon standard for development'. However, only new buildings which have zero net emissions should be described as 'net zero carbon buildings'.

Process - we recommend:

• 'Allowable Solutions' should be investigated as a potential option for delivering a 'net zero carbon' standard for new development.
• If introduced, 'Allowable Solutions' should apply to both domestic and non-domestic new buildings.
• Investigation of 'Allowable Solutions' should recognise the need for simplicity and clarity of such solutions both in application and in substantiation of benefit.
• Should regulation incorporate 'Allowable Solutions', the term 'net zero carbon' new building should apply only to development where emissions are reduced to zero without off-site 'Allowable Solutions'.
• That Scottish Government works with industry and other UK administrations in investigating 'Allowable Solutions'.