Why does a Sustainability Statement matter, how does it relate to energy modelling, and when in the planning process do you actually need one? We’re asked a variation of this question a lot, so here’s the full answer.
In this blog you’ll learn:
- What a Sustainability Statement actually is and what it needs to demonstrate
- When you need one – including how Green Belt, Grey Belt and brownfield land change the picture
- What a separate Energy Statement covers and how it differs from a Sustainability Statement
- The practical starting steps for both documents
What is a sustainability statement?
A Sustainability Statement is a comprehensive document covering the environmental impact of a planned development. It should demonstrate how the development addresses the sustainability policies set by the Local Authority, using a SAP calculation to evidence planned energy efficiency, water conservation, flood risk and drainage. It will also typically cover:
- transport links
- community impacts
- health and wellbeing
- construction materials
- materials sourcing
- pollutive and ecological aspects
- best practice site management.
A Sustainability Statement isn’t a formality – a carefully crafted, well-considered one can be genuinely decisive for getting planning approval. It’s usually prepared at the pre-planning stage, submitted alongside the planning application itself and needs to reflect your specific local authority’s requirements. Planning policy varies by area, so there’s no single template that fits everywhere.
Do I Need A Sustainability Statement?
Whether you need a Sustainability Statement depends primarily on your Local Planning Authority’s (LPA) validation requirements and local plan policies, rather than a single national mandate. The NPPF sets national policy, but it doesn’t mandate a “Sustainability Statement” by name – whether one is required comes down to your LPA’s Local Validation Checklist. That said, certain site classifications and project scales will almost certainly require one:
- Green Belt & “Grey Belt” sites: Under the National Planning Policy Framework (NPPF), development on Green Belt land generally requires demonstrating “very special circumstances” to gain approval – a different test from the “exceptional circumstances” standard used when altering Green Belt boundaries during the Local Plan process itself. Demonstrating exceptional sustainability, net-zero alignment, and ecological enhancements is often critical to building that case. Under national reforms targeting “Grey Belt” land (low-quality or previously developed sites within the Green Belt), developments must also meet strict “golden rules” on green infrastructure, local connectivity, and environmental performance.
- Brownfield & urban developments: For brownfield (previously developed) land, requirements are set at the local authority’s discretion. Major developments almost universally require a Sustainability Statement, whereas single builds depend on specific council policies. In many areas, LPAs actively require developments to not just meet, but exceed, baseline Part L Building Regulations targets.
Because requirements vary significantly by council, it’s essential to check your LPA’s local validation list early.
Getting Started on Your Sustainability Statement
You’ll typically commission a Sustainability Statement at the beginning of your project, in support of a planning application. The first step is contacting your Local Authority to find out their specific requirements.
From there, you or your architect should provide as much information as possible about the proposed plans, including:
- Floor plans, elevations, sections and site plans
- Insulation type and thickness
- Air tightness value and U-values of openings
- Specification of heating systems and hot water generation
- Percentage of low energy lighting
- Ventilation system specification and renewable technologies
- Accredited construction details
- Flood drainage strategy and wider site details
- Traffic counts
- Information on how and where materials are sourced
- Information on the wildlife and plants in the area
Once collected, this information is input into SAP software for assessment, generating a Sustainability Statement that sets out the sustainability options under consideration and their respective impact on CO₂ emissions and the wider environment.
A real-world example of exactly this process, supporting Cotswold Homes’ planning application in South Gloucestershire.
What Is an Energy Statement, and Do I Need One?
When submitting plans for a new development, you’ll often need to submit an Energy Statement alongside your planning application and Sustainability Statement, at the very start of the project process.
These submissions – also known as Energy Strategy Reports – need to demonstrate how the development will meet local energy efficiency targets. Since these targets are set by your Local Planning Authority rather than nationally, you’ll need to look up your specific authority’s carbon emission and renewable energy targets. As the Energy Statement is closely tied to Building Regulations, a planning authority might, for example, require a 10% improvement over Part L emissions, or a requirement that 10% of the development’s energy supply comes from renewables – the exact figures and policies vary by authority. These statements are prepared using energy modelling, incorporating a Low or Zero Carbon (LZC) Feasibility Study into the same report.
What Does an Energy Statement Include?
The Energy Statement is a detailed calculation report showing how a development will achieve its Local Planning Authority’s emission target. It needs to include:
- A calculation of the predicted energy/CO₂ emissions of the development
- The energy efficiency of the building fabric
- Baseline annual predicted energy demand and projected carbon emissions
- The contribution of each proposed renewable energy technology
- Cost information for technically feasible LZC/renewable technologies
- Feasibility of district or community heating
- A summary of the benefits of the various low energy technologies considered
- The total estimated reduction in the development’s baseline carbon emissions and/or energy demand
Getting Started on Your Energy Statement
- The process typically works as a loop until the target is met:
- Calculate total regulated energy after deducting energy efficiency savings.
- Calculate the percentage of decentralised, renewable or low carbon sources.
- Calculate predicted energy savings.
- Assess the feasibility of different energy technologies for the development.
- Calculate the energy savings of renewable energy options as a percentage of total regulated energy, checking this against the target set by the Local Planning Authority.
- If the target isn’t met, return to step 2 and revise the approach. If it is, submit the Energy Statement alongside your Planning Application and Sustainability Statement.
What’s next?
Energy and Sustainability Statements are supporting documents to a planning application, and requirements vary across local authorities – but a reduction in carbon emissions and use of low energy technologies can be expected in some form almost everywhere, and some authorities will also expect BREEAM or other sustainability standards to be met. Cotswold Homes’ Engine Common scheme is a good example of what that looks like in practice, from Sustainability Statement through to a fully modelled Energy Statement.
Get in touch with our friendly team when you’re ready to start your Sustainability or Energy Statement.
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