A Sustainability Statement is a document that shows how a proposed development addresses the environmental policies set by its Local Planning Authority – energy efficiency, water conservation, flood risk, materials, transport and biodiversity among them. Why does it 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
- How it differs from an Energy Statement
- The practical starting steps
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 and 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.
How Does This Differ From an Energy Statement?
The two get used interchangeably in practice, and some Local Planning Authorities do request them as a single combined report – but where they’re requested separately, it’s worth knowing which one you need. An Energy Statement focuses specifically on energy demand, carbon emissions and the renewable technologies proposed to meet a council’s targets. A Sustainability Statement is the broader document: it covers that same energy and carbon ground, but also addresses water efficiency, drainage, material sourcing, biodiversity and construction waste that an Energy Statement doesn’t touch.
If your project’s requirement is specifically energy- and carbon-focused rather than the wider environmental scope covered here, this companion guide sets out exactly what an Energy Statement needs to include:
Do I Need A Sustainability Statement?
In short: almost certainly, if your site sits on Green Belt or Grey Belt land, or if you’re proposing a major development on brownfield or urban land – and quite possibly otherwise too, depending on your Local Planning Authority’s Validation Checklist.
Whether you need one 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. If you’re building in South Gloucestershire specifically, our guide to the council’s PSP6, CS1(8), CS3 and CS4 policies sets out the exact local thresholds.
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.
If your project’s scope is specifically about how to structure and write the statement itself for a construction scheme, our best-practice guide to sustainability statements for construction projects covers that in more detail.
A real-world example of exactly this process, supporting Cotswold Homes’ planning application in South Gloucestershire:
Cotswold Homes, Engine Common: A Combined Fabric and Renewables Strategy for New Build Carbon Compliance
View Case StudyWhat’s Next?
Sustainability and Energy 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.
We prepare Sustainability Statements and Energy Statements for residential and commercial planning applications across the South West and beyond.
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