CS2: Delivering Sustainable Design and Construction

CS2: Delivering Sustainable Design and Construction

New development both residential (including conversions) and non-residential should demonstrate a commitment to sustainable design and construction, increasing energy efficiency through design, and prioritising the use of sustainable low or zero carbon forms of renewable energy generation in order to increase the sustainability of the building stock across North Somerset.  The greatest potential for energy saving opportunities is likely to be at larger scale developments particularly at the Weston urban extension and Weston town centre.  In addition these areas are expected to demonstrate exemplar environmental standards contributing to the objectives of Policy CS1, and adding value to the local economy.

When considering proposals for residential development the council will:

1) require designs that are energy efficient and designed to reduce their energy demands;

2) require the use of on-site renewable energy sources or by linking with/contributing to available local off-site renewable energy sources to meet a minimum of 10% of predicted energy use for residential development proposals involving one to nine dwellings, and 15% for 10 or more dwellings; and 10% for non-residential developments over 500m² and 15% for 1000m² and above;

3) require Code for Sustainable Homes Level 4 for all new dwellings and higher levels across major developments of 10 or more dwellings.  BREEAM 'Very Good' will be required on all non-residential developments over 500m2 and 'Excellent' over 1000m2;

4) require all developments of 10 or more new homes to incorporate 50% constructed to the Lifetime Homes standard up to 2013 and 100% from 2013 onwards.

In moving towards zero carbon development, the council will ensure that sustainable principles are established in the new proposals from the outset. 

Site-wide renewable energy solutions are expected at the Weston urban extension to serve the new development and ensure it contributes to a low carbon development, recognising that a significant proportion of the development will extend beyond 2016 when all new homes are intended to meet zero carbon standards.

This policy contributes towards achieving the objectives of Planning Policy Statement 1: Delivering Sustainable Development.

Background

The domestic housing sector accounts for around 27% of the total UK carbon emissions. Government is committed to moving towards zero carbon for all new homes by 2016 as set out in the Building a Greener Future, policy statement (July 2007) and all non-domestic buildings by 2019 through a 10 year programme of increasing building performance through the Building Regulations. This policy is part of a wider local policy framework necessary to address climate change and reduce the impact development has on the environment, linking to the council's Sustainable Community Strategy and Corporate Plan.

Given that North Somerset has to deliver a significant amount of additional homes up to 2026 there is a pressing need to ensure new homes are as sustainable as possible and minimise their impact on the environment and global warming, as well as addressing issues such as fuel poverty and health.

The Code for Sustainable Homes has been developed as a national standard to drive the sustainability of new homes. The code is structured around six performance levels, Level 1 being the entry level (representing a 10% reduction on current part L Building Regulations and Level 6 representing 'zero carbon' (a 100% reduction on Building Regulations). Credits are awarded across the areas of energy and CO2 emissions; water; materials; surface water runoff; waste; pollution; health and wellbeing; management; and ecology with most weight (or credits available) being placed on the energy and CO2 emissions element.

Lifetime Homes

The Government has a stated aspiration that all new homes will be constructed to the Lifetime Homes standard by 2013 (see Lifetime Homes, Lifetime Neighbourhoods, DCLG 2008). Lifetime Homes have 16 design features that ensure a new flat or house will meet the needs of most households. The features focus on accessibility and design features that make a home flexible enough to meet the demands of a lifetime in order to reduce the requirement to move to alternative accommodation as a family grows, as circumstances in health change or as the household ages. By facilitating adaptation to future lifestyle requirements, such homes contribute to sustainable development. With an increasingly ageing population in North Somerset with an estimated 24% of the population being over the age of 65 by 2026[1], the council considers it appropriate to require a proportion of housing within new developments to meet Lifetime Homes Standards.

The Core Strategy approach

The policy sets out a broad aspiration for all new buildings including conversions to be sustainable, linking to policy CS12 on design and to reduce the demand for and use of non-renewable forms of energy.

It implements national standards on home sustainability and sets out a trajectory to meeting zero-carbon homes by 2016, gradually increasing standards for small scale residential development, and setting high standards where there are most opportunities to deliver. It also uses the industry standard BREEAM assessment methods to determine the sustainability of non-residential buildings. 

Pink town houses

The Core Strategy requires all new homes to meet as a minimum code Level 4. Higher code levels will be required at the Weston urban extension where the economies of scale can be capitalised on and energy infrastructure can be built into the development from the outset. In addition applications for large schemes will need to demonstrate how the scheme incorporates higher standards over the duration of the development. In all cases flexibility will be exercised where viability and deliverability are critical factors.

Policy CS2 also encourages the use of on-site renewable energy to support the sustainability of new development.

How and where the policy will be delivered

By implication the implementation of this policy will be linked to the broad distribution of development, but exemplar standards are expected at the urban extension to Weston and the Weston town centre/gateway area. These areas are where most development is directed and where most investment is required, where the economies of scale, comprehensive and phased approach to development can be of benefit.

New buildings should in the first instance be designed and constructed to be energy efficient performing at least to current Building Regulation standards. Using the principles of 'passive' design, including high insulation levels, solar heating, natural lighting and ventilation, thermal mass and passive cooling, buildings can demonstrate a reduced energy demand and subsequent reduced carbon emissions.

Low or zero carbon technologies

Having achieved a reduced energy demand through energy efficient design, the second stage is to consider the use of decentralised, renewable and low or zero-carbon technologies. Where viable and feasible this should provide as a minimum 15% of the predicted energy demand (10% for one to nine dwellings) of the building measured in kilowatt hours (regulated energy) of the development in total thus further reducing the reliance on fossil fuels, and reducing the carbon emissions still. Using low or zero-carbon (LZC) technologies will also contribute to achieving a rating against the Code for Sustainable Homes.

Policy CS2 does not prescribe the type of renewable energy for individual applications but instead advocates that a range of technologies be explored choosing the one that gives the best environmental performance, is cost efficient and has no adverse impacts on the surrounding area. In each instance through the development of the design and feasibility, the available wind, solar and other resource should be considered. When it is considered that achieving the stated percentage of renewable energy is unfeasible or unviable, evidence should be supplied demonstrating that the range of available technologies has been explored. In these cases, where a sufficient case is put forward a reduced percentage may be negotiated. An energy statement should be submitted with the planning application explaining the approach to energy on the development.

Site-wide energy schemes

On major developments (10 or more dwellings) district heating and power schemes for example Combined Heat and Power (CHP) will be encouraged to serve the new development. Prospective applicants are encouraged to undertake feasibility assessments exploring the different technologies available and financial implications at an early stage. Research has found that it becomes more cost effective to integrate site-wide renewable energy solutions (A Cost Review of the Code for Sustainable Homes, (2007), English Partnerships and the Housing Corporation).

Prospective applicants are encouraged to discuss proposals with the council at an early stage in the development process in addition to engaging specialist advice particularly on large schemes. Applicants will be responsible for demonstrating the environmental sustainability credentials of schemes submitting energy statements and the necessary compliance documentation.

Further detail on implementing this policy will be made in a development management Development Plan Document and within a Supplementary Planning Document.

Alternative options and contingency planning

Alternative options relate to the target percentages of renewable energy, or the code levels, and how they relate to different scales or types of development, and when higher levels should be sought. Further evidence will be required on viability.

Monitoring and review

Monitoring will assess indicators relating to renewable energy and code levels.

1. Figures from ONS sub-national population projections 2008. [back]