Supplementary Planning Document, January 2020
The Brighton and Hove City Plan contains planning policies that are used to determine planning applications for new development. Planning policies set out how development proposals can be supported to make sure good quality development is achieved. The City Plan is available on the Council’s website, and relevant policies should be consulted before making a planning application for any extension or alteration. It may also be helpful to look up your address using the Council’s on-line map to see if there are any area-specific constraints relevant to the property.
Supplementary Planning Documents (SPDs) are produced to provide additional guidance, information or clarification on how the requirements of local planning policies can be met. SPDs do not carry as much weight as the City Plan policies but can be useful, additional guidance in preparing and assessing planning applications.
Any extension or alteration to a property requires careful thought in terms of planning and design in order to ensure it has a good fit with the existing environment.
It is also useful to discuss initial ideas for an extension or an alteration to a property with neighbours. All planning applications are subject to public consultation, so it is best to iron out any neighbour concerns at an early stage, however, agreement with the neighbour does not imply the application will be automatically approved.
It may be helpful to consider appointing an accredited professional to assist in drawing up the scheme or the planning application. The Royal Town Planning Institute (RTPI), Royal Institute of British Architects (RIBA), the Royal Institution of Chartered Surveyors (RICS) and Charted Institute of Building (CIOB) all provide details on their website of all accredited professionals.
A checklist at Appendix 1 of this document provides guidance on what documents, plans, photographs and details should be submitted as part of a planning application.
In determining planning applications the Council will make an assessment against adopted local and national planning policies, whilst having regard to other material considerations including this SPD. There are three main considerations outlined by planning policy that relate to extensions and alterations:
Further details on each of the considerations above are outlined within this Supplementary Planning Document. If the proposed works constitute significant changes to the property, consider engaging with the Council prior to submitting the planning application by applying for Pre-application advice. (Please see the Council’s website for further information on applying for Pre-application advice including what fees and documentation are required.)
This document offers guidance on how to comply with relevant planning policies and achieve the best possible extension or alteration. When developing a proposal, it is important to balance your own needs with the needs and rights of neighbours and also consider what is best for the wider community. This guide has been structured to help to achieve this balance. The document is set out as follows:
This guide ends with advice on further information to be submitted to assist the application and a glossary explaining the meaning of technical terms used.
Some extensions and alterations may not require planning permission. This is known as ‘Permitted Development’. Permitted development rights are detailed in the Town and Country Planning (General Permitted Development) Order 2015 (as amended). The permitted development rights have changed over time and they can sometimes be quite complicated to interpret.n Permitted development rights usually do not apply to: residential buildings which are not single dwelling houses, flats, listed buildings, or where there are planning conditions in place specifically removing permitted development rights relating to planning permissions. If the property is within a Conservation Area or an Article 4 designation, the ‘permitted development’ rights of the property will be affected. It will be useful to look at the guidance on permitted development rights available at the Planning Portal website.
This SPD is also a useful tool to achieve a high quality of design from extensions and alterations that fall within permitted development.
Understanding the local context will help proposals for extensions and alterations to take account of the important qualities and characteristics of the neighbourhoods or streets which help define them.
The city contains many residential areas and neighbourhoods each with their own distinctive identity and characteristics. The particular challenges for extensions and alterations therefore vary across different townscape types within neighbourhoods or streets, as do the opportunities. Streets, for example, are often characterised by a common design based upon the repetition of an architectural style and/or a setting which establishes a distinctive building rhythm.
It is acknowledged that some areas can accommodate change more easily by virtue of being more diverse in character compared to others. Some areas, due to their elevated position, may be more sensitive than others. This document recommends examining in detail the local context for any proposed development and relating the new extension/alteration to its surroundings.
Some areas of the city have been designated as conservation areas due to their special architectural or historic interest. Some individual buildings have been deemed so important that they have been statutorily listed. It is useful to check whether the property being extended is within a conservation area or is a listed building before making any plans for changes. A street directory of all conservation areas within the City can be found at on our website. This is particularly important as conservation areas may have special planning controls that apply. In all cases stricter policies special planning controls that apply. In all cases stricter policies apply to any alterations. Additional considerations relating to conservation areas, listed buildings and locally listed buildings are set out later in this document.
High density Victorian terrace in the Hanover area of Brighton
Detached single dwellings in the Hangleton area of Hove
Semi-detached properties in West Hove
This section outlines general principles for achieving a good design and therefore a well-designed extension or alteration.
It is important that extensions and alterations should have an attractive design and complement the character and appearance of the original property and, where relevant, the group of buildings of which it forms a part.
In Conservation Areas and where high quality historic buildings require extensions, it may be more appropriate to generally seek to introduce or retain the prevailing architectural features and character of the area. Where original architectural details to the property have been lost, these should be reinstated to enhance the character of the property and the wider streetscene. In most cases, new windows, doors and other details such as choice of materials should reflect the design and alignment of the existing fenestration of the building. More detailed guidance is available for properties in Conservation Areas in Section 5 of this document.
Neighbours have the right to enjoy their home without intrusion from inappropriate development at adjoining properties. Extensions and alterations will be expected to be designed to be respectful of neighbours’ privacy, daylight and outlook. Proposals should avoid loss of daylight or overshadowing of adjoining properties. In particular loss of light to main windows serving principal rooms (such as living rooms, bedrooms and kitchens) will be an important consideration.
Proposals should:
If you are intending on building or fixing anything directly on or close to the boundary of your property you are advised to refer to the Party Wall Act (which is a separate piece of legislation, not relevant to Planning and is a private civil matter), which relates to issue around land ownership and maintenance.
Rear extension: Fraher Findlay Architects – responding to topography
Extensions and alterations should be designed and constructed to deliver sustainable development which respects the environment. They are an opportunity to incorporate renewable energy sources and to potentially provide some urban greening to the property and to contribute to reducing Carbon emissions.
Useful References:
City Plan Part 1 Policy 10 CP10 Biodiversity, Brighton & Hove City Council, 2016 · Supplementary Planning Document (SPD11) – Nature Conservation and Development, Brighton and Hove City Council, 2010
Examples of the many types of integrated bee and swift habitats
A biosolar roof - combining solar energy with biodiverse green roof habitat
The detailed guidance set out below is not exhaustive or definitive. Its purpose is to guide the design of new extensions/alterations to enable a better fit with the host building as well as minimise any visual intrusion on the street scene or character including avoiding harm to neighbours’ amenity. Variations to these guidelines may be acceptable where it can be demonstrated that no harm is caused to existing neighbouring amenity or to the character of the local area. Innovative and contemporary solutions that enhance a sense of scale, proportion and place are encouraged.
The Council will seek to ensure that rear extensions are of a suitable scale to remain subservient to the character and appearance of the main property and are sensitively designed. Particular care is needed if the property is located at the end of a terrace or is a corner property as an extension to the rear is likely to be visible from the street. The following guidance should be followed where relevant:
Lean-to rear extension: Archangels Architects, Brighton & Hove
Two storey rear extension: LW Architects, Brighton & Hove
Spacing between buildings helps to define the character of an area. Side extensions therefore should ensure that rhythm of spacing between buildings is maintained in order to minimise the potential ‘terracing’ effect. In terms of semi-detached and terraced properties, the proposed extension should avoid unbalancing the attached properties.
Extensions to the front of buildings will normally be highly visible in the streetscene therefore particular care should be taken to ensure they do not detract from the appearance of the property, or the general character of the street. Particular regard should be given to the materials, detailing, prevailing building lines and fenestration of front extensions to ensure they relate well to the original building and the streetscene.
An example of a two storey front extension
An example of a discreet porch extension
The rhythm and continuity of the rooflines to buildings are often a key visible element within a streetscene therefore any poorly designed or excessively bulky additions can have a significantly harmful impact on both the appearance of the property and the continuity of a streetscape. In addition, consider the following guidance:
A dormer is a window that is typically set vertically on a sloping roof. The dormer has its own roof, which may be flat, arched, hipped, gabled, or ornamented. Dormers can add elegance and appeal to the property, but they can also end up making the property look out of proportion, so the design should be carefully considered in line with following guidance:
Dormer windows on the rear roof slope will normally have limited or no impact on the streetscene, however, they should clearly be a subordinate addition to the roof set appropriately in the roof space to avoid looking disproportionate to the property.
As a rule rear dormers should be appropriately set in from the side, set down from the ridge and set up from the eaves so as not to appear as an additional storey or appear “top heavy”. In addition, further consideration should be given to ensure that:
Dormer windows on the front roof slope will have a greater impact on the streetscene. Front dormer windows should be sensitively designed to respond to their prominent setting. Depending on the character of the street, front dormers may be acceptable, and where acceptable they will generally be limited to a single dormer extension. Exception may be made in some areas of the City where front dormer windows are a common feature and where the size of the property can comfortably accommodate more than one dormer.
Front dormers should be:
Normally it is expected that dormer positioning will align well with the windows below. As in the case of rear dormers in certain cases it may be preferable for dormers to be positioned on the centre line of the building or the centre line of the space between the windows below.
Balconies and roof terraces can provide valuable and welcome amenity space for properties; however, in many cases they can significantly affect a neighbour’s privacy and create a sense of overlooking, particularly if they are located where it is possible to look into gardens or windows that previously enjoyed privacy. The presence of balconies and roof terraces may also result in noise disturbance, particularly to nearby windows, and can also be harmful to the appearance of a building. Careful consideration needs to be given to the location and design of a balcony or a terrace including any associated balustrades
Balconies and roof terraces at the front and rear of the building including any other prominent locations visible from the street are only acceptable where they do not harm the appearance of the building and streetscene.
The urban character of certain parts of Brighton and Hove means some properties already overlook one another. Balconies and roof terraces that create new overlooking or make existing situations much worse are unlikely to be approved. In such cases screening can provide the required privacy to all parties but their detailing and size must also be appropriate to the character of the building and area.
The construction of outbuildings in rear gardens and other undeveloped areas can often have an impact upon the amenity, biodiversity and character of an area.
The siting, location, scale, materials and design of the outbuilding should have a minimal visual impact on, and be comfortably accommodated within the host garden. The maximum size of the outbuilding (or number of outbuildings) will usually be determined by the location and the size of the garden area.
The character of a property can be enhanced by the alteration or addition of new windows or doors that align with the style and character of the original. Good quality window design and placement can contribute to the general appearance of buildings, help maintain the rhythm of the streetscene, particularly on large blocks of flats and more traditional building forms where the continuity of fenestration is a key element. New and replacement windows should:
In most cases windows positioned to match the symmetry of those in the existing building help maintain the aesthetics and character of the building.
The size, design and siting of rooflights should not significantly change the appearance of the building externally and should not introduce detrimental visual elements into the streetscene.
Irregular rooflight sizes and positioning should be avoided, and in particular will be resisted on street elevations.
Garden walls, fences, railings and hedges are all important elements in the streetscene. They provide the distinction between the private space and the public space of the pavement and street.
Differing boundary treatments along a street can result in a cluttered, disordered appearance. This effect is particularly noticeable in streets of terraced or semi-detached houses. Alteration of front boundary walls and fences will need to:
The design and height of boundary walls (including pillars), railings and gates should relate to the character of the street/surrounding area, particularly if of a uniform character. Details such as railed sections and pillars can reduce the visual impact of a high wall. The removal of a front boundary wall or hedge and the development of the front garden into a forecourt for parking will be resisted where it would have an adverse impact on visual amenity or the character of the streetscene.
Satellite dishes and aerials including cables, ducts and pipeworks can add visual clutter and detract from the appearance of a building and streetscene if located in a prominently visible position. It is therefore important to ensure that:
All cables, ducts and pipework should run internally or up the rear wall in discrete positions and be coloured/painted to match the background wall. Flues, ventilation units and other services that appear as 'add-on' elements will not normally be accepted in elevations visible from streets.
Some additional considerations relating to Conservation Areas, listed buildings and locally listed buildings are set out below but proposals should also take account of the policy guidance in SPD09 on Architectural Features.
Brighton & Hove has over 3,400 listed buildings which are of special architectural or historic interest. Where a building has been listed, it is listed in its entirety, which means that both the exterior and the interior are protected. The listing includes any object or structure fixed to the building (such as railings or boundary walls), and any object or structure within the curtilage of the building, which although not fixed to the building, forms part of the land and has done so since before 1 July 1948. Formal ‘Listed Building Consent’ is required from the Council for any works that would affect a building’s special character, alongside an application for planning permission (if required). A directory of all Listed Buildings within the City can be found at http://www.brighton-hove.gov.uk/index.cfm?request=c1001398. It is worth noting that:
Many buildings within Brighton & Hove are located within Conservation Areas and/or have been identified as buildings of local interest. A street directory of all Conservation Areas within the City can be found at http://www.brighton- hove.gov.uk/index.cfm?request=c1001585. Any proposal for extension or alteration therefore must seek to preserve or enhance, and not cause harm to, the special character or appearance of the area. Proposals for extensions and alterations that affect historic buildings and those in Conservation Areas are expected to demonstrate
Extensions and alterations to Buildings of Local Interest and buildings within conservation areas should be completed to a high design standard, with materials and detailing matching those of the host building. The council will expect the submission of material samples and design details where appropriate, for approval as part of the application. In addition consider following guidance:
Extension of a listed building: Landivar Architects, Patcham, Brighton
On historic buildings the roof is often the ‘crowning glory’ and an integral part of the overall design. Alterations to the shape or form of the roof, the use of unsympathetic materials and the loss of original features can all have a serious effect on the appearance and character of historic areas. The additional following guidance applies:
Traditional dormers or rooflights were located to provide a small amount of daylight and ventilation to the loft or attic rooms, or to provide access onto a valley roof for maintenance purposes. Larger ones were sometimes used to light a stairwell. Lantern lights were often also used where more light was required to stairwells and other areas. Historically, rooflights were small and confined to rear roof slopes or hidden valleys. Where significant amounts of daylight are needed for rooms in the roof space, a dormer window is often a more architecturally and historically appropriate solution, but
Listed building extension: PCMS Design, South Oxfordshire
On historic buildings windows contribute to the character of the building through their design, materials and workmanship. Any proposal for new or replacement windows should note that:
Replacement windows on a listed building: ABIR Architects, Lewes
Upon receipt of an application for planning permission, officers will undertake an initial consideration of the proposed development. It is important that the information provided to the Council clearly demonstrates how the extension or alteration to the property is being proposed. Mandatory requirements The following documents are mandatory requirements for most planning applications including householder planning applications and must be provided with your application at the point it is made:
It will be helpful to officers if the following documents, drawings and photographs are submitted with the application (in addition to the mandatory requirements):
Direction removing some or all permitted development rights, for example within a Conservation Area or curtilage of a listed building. Article 4 directions are issued by local planning authorities.
The whole variety of life encompassing all genetics, species and ecosystem variations, including plans and animals.
A term relating to Conservation Areas or Listed Buildings but also to the appearance of any rural or urban location in terms of its landscape or the layout of streets and open spaces, often giving places their own distinct identity.
Local authorities have the power to designate as conservation areas, any area of special architectural or historic interest. This means the planning authority has extra powers to control works and demolition of buildings to protect or improve the character or appearance of the area. Conservation Area Consent has been replaced by planning permission for relevant demolition in a conservation area.
Part of a roof that meets or overhangs the walls Flank window: A side window Gable: The vertical triangular end of a building from eaves to ridge
Pitched roof where two roof planes meet at the ridge
A building of special architectural or historic interest. Listed buildings are graded I, II* or II with grade I being the highest. Listing includes the interior as well as the exterior of the building and may include buildings or permanent structures (e.g. wells within its curtilage)
Locally important building valued for contribution to local scene but not meriting listed building status
Opaque glass reducing visibility
A term used to describe the impact where the effect is dominating
A term used to describe the effect when a development or building affords an outlook over adjoining land or property often causing loss of privacy
The effect of a development or building on the amount of natural light presently enjoyed by a neighbouring property resulting in a shadow being cast over that neighbouring property
Top line of the roof Terracing effect: A term used to describe the closing of gaps between houses by extending the houses sideways
A mechanism for securing the preservation of single or groups of trees of acknowledged amenity value. A tree subject to a tree preservation order may not normally be topped, lopped or felled without the consent of the local planning authority
When designing an extension it is important to consider the level of sunlight and daylight currently enjoyed by the neighbouring properties. Extensions that are poorly designed and sited can result in unacceptable impact on neighbour’s amenities. It is a common practice to use the 45-degree rule to measure such impact. The 45 degree rule is set out in the Building Research Establishment (BRE) document ‘Site Layout Planning for Daylight and Sunlight: A guide to good practice (2011) and is an accepted rule of thumb test to determine whether or not further detailed daylight and sunlight tests are required.
The primary concern of the 45-degree test is the level of light and unobstructed view from a habitable room window. Rooms such as bathrooms, halls, utilities and landings/stairs do not require this consideration. Whilst this test is more common to residential dwellings it is also suited to non-residential properties, where occupants have a reasonable expectation of daylight, for example schools, hospitals, hotels, offices and workshops.
The 45 degree test normally works for extensions that are perpendicular to a window in a neighbouring property. A centre line is marked on the plan of the neighbouring window that may be affected by the extension. A 45 degree angle is drawn from the outer most part of the extension toward the window. If the 45 degree line extends above or beyond the centre line of the window, there is a chance there will be an adverse effect on daylighting in the neighbouring property. If the 45 degree line does not extend beyond the centre point of the window, it would suggest the neighbouring property would continue to receive adequate natural daylight and would not be affected by the proposal.
Plan diagram showing footprint area in inside the 45 degree projections
Elevation diagram showing footprint area inside the 45 degree projections