The advice provided throughout this document is structured on the Design Guide SPD Part 1 – Design Principles and links back to relevant sections provided in the subtitles e.g. Context. Applicants should, therefore, use these documents in conjunction.

The site-specific guidance for Small Sites that follows is split according to the typologies set out in Fig. 06 opposite. The guidance addresses common design challenges and opportunities and provides a framework for developers to consider when proposing new schemes.

Across each site typology, built precedents provide examples of best practice and exemplars explore how certain development sites could be approached.

Small site development typically occurs through either:

• Addition: additional homes are built on vacant spaces
• Redevelopment: existing buildings are adapted or demolished and replaced with additional homes
• Conversion: existing buildings are adapted involving some form of extension. Other advice on extending residential properties can be found in the Design Guide SPD Part 2 – Building Alterations and Extensions document

Preparing development proposals

Working with specialists and building a design team

The Council strongly recommends engaging with high quality specialists early in the design process to provide advice, develop and coordinate the design and submit a planning application.

The RIBA and CIAT are valuable resources to review when seeking architects or architectural technologists to employ. On more complex projects, planning agents can help with navigating the planning process – the RTPI can help with finding a planning specialist.

Other consultants required may include structural, civil and electrical engineers, landscape architects, quantity surveyors, conservation architects, ecologists and arboriculturalists. An architect or planning expert will be able to confirm whose services are required for the project.

Neighbour engagement

Pro-active, early and ongoing engagement and consultation with nearby residents and local community groups is strongly recommended as this can draw upon local knowledge to develop plans, allowing people to meaningfully contribute to shaping the places they live, work and play in. Applicants should provide evidence of how this engagement has been used to shape their proposal.

Permitted Development (PD) rights

Some development can be undertaken under permitted development (PD), meaning no planning permission is required. Rights are set by the Government and do not fall under Council control. The Planning Portal has up-to-date guidance on which works constitute PD. Some permitted development is subject to prior approval and requires an application to be submitted to the Council for approval before starting any construction works.

PD rights can be removed by the Council using Article 4 Directions which bring development back under planning control.

For example, across Bexley, the change of use of Class E space (i.e. offices and shops) to residential homes within the borough's town centres and the change of use of buildings from commercial, business and service to residential within designated industrial locations are protected by an Article 4 Direction.

The scope of works that can be undertaken under PD can be limited and there is typically less control over the space created. The Council would recommend the planning process to enable applicants to make full use of a development site. For example, the upward extension of an existing building to create additional homes is PD subject to prior approval, however there are limitations as to the extent of works permitted.

Works proposed to flats, houses converted into flats, maisonettes and listed buildings are often excluded from PD rights and would require planning permission.

Conservation Areas and listed buildings

Conservation Areas are so designated to protect the special architectural and historical value of these areas. When proposing development within or adjacent to a Conservation Area, applicants must demonstrate how the proposal will preserve or enhance the character and appearance of the area. The Council's Conservation Area and Appraisal and Management Plan for each Conservation Area provides guidance on what is deemed suitable development.

At the time of publishing the Council has four Article 4 Directions applicable to Conservation Areas, which may limit PD rights in these locations.

Listed buildings are subject to Listed Building Consent which is separate from planning permission. PD rights are limited to listed buildings. The determination process will consider the potential harm to the features of listed buildings or their setting, and development which falls into these categories must be sensitively designed to respect the special architectural character or historic interest of the building.

The planning process and the benefits of the pre-application service

Given the intricacies often involved in developing small sites, utilising the Council's pre-application service is strongly recommended.

This service provides the opportunity to discuss design development with various, relevant Council officers who can offer clarity on what will be both expected and accepted upon planning submission.

The amount of information required with a planning application will vary according to the complexity and scale of development. This can be discussed with the Council during the pre-application process. To enable a smoother application process, submissions should comply with the Council's validation checklist which details the correct formats information should be submitted in.

One key required document is the Design and Access Statement (DAS) which is used to explain how the proposal has developed. Fig. 07 outlines what information should be included in a DAS – note, this list is not exhaustive.

Making a planning submission

Where planning permission is required, applications must be submitted to the Local Planning Authority, and further information is available on the Council's website.

Summaries of key issues to be addressed and demonstrated in planning applications are provided at the end of each section for clarity.

Demonstrating an understanding of the local context

In line with Bexley Local Plan Policy DP11 Achieving high quality design, D 01 of the Design Guide SPD Part 1 – Design Principles sets out the importance of all proposals being informed by an understanding of the local context. This is especially important on small sites which are often faced with multiple constraints. Applicants should provide a Character Appraisal, as set out in D 01, presenting this during any pre-application discussions and the application stage.

Planning constraints

Whilst undertaking a Character Appraisal, applicants may identify a number of planning policy areas, or planning constraints, applicable to a site. These areas are defined zones where additional planning controls exist and will need to be considered during design development.

Applicants should refer to the key diagram in the Bexley Local Plan for significant planning constraints and the Bexley Local Plan Policies Map is a useful resource for identifying other constraints specific to a site. Fig. 08 summarises some of these constraints and where applicants can find additional guidance and information.

This list is not exhaustive and thorough research into a development site should be undertaken to determine any other controls.

Designing functional new homes

Applicants should refer to the Spatial Quality section of the Design Guide SPD Part 1 – Design Principles which provides guidance on designing policy compliant housing that accounts for neighbouring homes by ensuring sufficient separation distances, privacy, outlook and access to light and amenity between existing and new homes.

Guidance includes prioritising the design of dual and triple aspect homes and the avoidance of single-aspect dwellings, especially those that are north facing or contain three or more bedrooms. It outlines how to meet internal space standards and provide suitably-sized and appropriately located communal and private amenity space alongside ancillary spaces such as cycle and refuse stores.

Further, detailed guidance for refuse and cycle storage and cycle and car parking is provided in the Design Guide SPD Part 2 – Technical Handbook.

When developing proposals, applicants should consider how a community's specific cultural requirements can be addressed in the design, undertaking engagement with residents and local stakeholders to understand these requirements and how they can be embedded in the design.

Similarly, applicants are encouraged to consider the different ways people may live and work, providing space for separation between home- and work-life, for example through the provision of a flexible room that can be used as a home office and a bedroom.

Designing for climate resilience

Several policies in the Development Plan require new developments to demonstrably mitigate against climate change. D 13 and D 14 in the Design Guide SPD Part 1 – Design Principles provides guidance on how this can be achieved to ensure the energy hierarchy is followed.

The Council supports a fabric first approach to new development, and applicants must develop proposals that embed climatic sustainability within the architectural and landscape proposals.

This means making choices from the outset that will reduce operational energy consumption, such as incorporating external shading and overhangs, and avoiding overly large window openings that will result in overheating to minimise the reliance on mechanical equipment. Opening sizes should be balanced with ensuring sufficient daylight and sunlight to all homes.

Applications should prioritise the use of renewable energy generation sources that provide alternatives to traditional gas boilers. Justification should be provided where certain sources are considered and discounted.

Circular economy principles must be employed and, where possible, the reuse of materials and buildings should be considered. Robust building materials should be chosen to reduce the need for frequent maintenance. Sourcing local materials and therefore reducing the carbon emissions of a project should be a priority.

Where existing buildings form part of a development, upgrading the existing building to improve energy efficiency and reduce user reliance on resources should be explored. The Design Guide SPD Part 2 – Building Alterations and Extensions sets out guidance for retrofitting works.

Reducing the amount of water consumed by residents can be addressed by providing means for rainwater harvesting and promoting grey water reuse and installing water-saving kitchen and bathroom fixtures and fittings.

The greening of urban environments is vital to enhancing biodiversity, improving air quality and supporting Bexley's wildlife and natural habitats. A landscape-led approach to development is strongly encouraged, and the landscape design should be developed simultaneously with the architectural proposal.