Extensions to Domestic Dwellings

Transcription

1 Extensions to Domestic Dwellings Supplementary Planning Guidance Notes Environment and Planning Services Directorate of Development

2 Extensions To Domestic Dwellings Supplementary Planning Guidance Note Preface The guidance contained in this document is provided to assist developers and the general public when submitting planning applications. It supplements and expands upon the Policies and Proposals of the Doncaster Unitary Development Plan (UDP). The UDP contains both the strategic and the local planning policies to guide development in Doncaster, and is used by the Council for development control purposes. Those UDP policies most relevant to this subject are ENV14, PH11, PH13, ENV25 and ENV32, and must be complied with. It is not possible, however, for the UDP to address in detail all the issues raised by the many types of development. The Council is therefore producing a number of Supplementary Planning Guidance (SPG) documents. A full list is contained in the UDP. SPG may be taken into account as a material consideration by the Council when determining planning applications. It is hoped that this Guidance will cover most eventualities, including all the main guidelines which a prospective applicant should bear in mind when considering development proposals. Free advice is also available however from the Directorate of Borough Strategy and Development and all applicants are urged to make early contact. The contents of this note relate to all extensions to domestic dwellings, and will be taken into account as your planning application is processed. However, as it is not possible to anticipate the circumstances that may arise for each individual dwelling, each application will be judges on its own merits. Do I need planning permission? Planning permission is not always required for extensions to dwellings. Proposals to extend a property and which satisfy all of the following criteria, will not generally require a specific planning permission: 1

3 The total cubic size of the extension/conservatory (when added to any previous extensions/conservatories made to the property, or any detached garage/other ancillary outbuilding, located within 5m of the dwelling or within 5m of the proposed extension/conservatory) does not exceed 70 cubic metres in the case of a semi or detached property, or 50 cubic metres in the case of a terraced property or in a Conservation Area. In an area designated as Countryside Policy Area, extensions should not exceed more than 20% of the volume of the original dwelling (over and above the criteria in the previous paragraph). No part of the extension exceeds the height of the highest part of the roof of the original dwelling. No part of the extension is closer to any highway than any part of the original dwelling. In the case of an extension which exceeds 4m in height, no part of it lies within a distance of 2m from any boundary. The area of ground covered by buildings within the curtilage (excluding the original dwelling) does not exceed fifty percent of the garden area. However, you should not simply rely upon these guidelines to determine whether your proposal requires planning permission. A completed householder enquiry form will allow a planning officer to determine whether or not planning permission is needed. These forms can be obtained from Danum House (Planning) reception, or by telephoning (01302) , or Notifying your neighbours You are strongly advised to discuss your proposals with your neighbours before submitting your planning application, because depending on the size and location of your extension, they may be affected by it. A section will be available on your application form for you to obtain your neighbour s signatures and find out if they object to your proposals. Once your application 2

4 has been submitted the Council will notify your nearest neighbours who will be invited to make comments. Any comments received will be taken into account when determining your application. Design and layout considerations When considering applications for domestic extensions, the local authority will consider the impact that the extension may have on both the dwelling itself, on the immediate neighbourhood, and on the neighbours. Appearance - A badly designed extension may have a considerable impact on the character of an area. The main aim may therefore be for the extension to look as though it had been designed as part of the original dwelling, and not added at a later date. However, where an extension is proposed in a Countryside Policy Area or Greenbelt, a design which differs slightly from the original dwelling may be required, in order to minimise the impact of the mass and scale of the dwelling on the countryside area. Roof - Any two-storey extension to a house with a pitched roof should have a roof of a similar form with roof slopes to a similar pitch. Single-storey extensions should also preferably have a matching pitched roof, in particular where any such extension is visible in the street scene. It is important to note that, whilst flat roofs may be marginally cheaper, a pitched roof is superior in both design and performance in the longer term. Size and scale - Generally, extensions should be smaller than the existing dwelling. An extension that is larger than the existing house will appear out of scale. The ridge and eaves lines of any extension must be level with or lower than those of the existing dwelling. In some cases it may be better to make a distinct break in both the roofline and wall-line, to ensure that the extension remains secondary to the original dwelling and to avoid unsightly matching in of old and new materials. The scale of the different types of extension are discussed later in this document. Doors and window - Window and door openings on extensions must match the size, proportion and positioning of those on the original dwelling. This includes dormers. For example, if the original windows have a vertical emphasis, those in the extension should also have a vertical emphasis. Window materials should also match the existing. 3

5 Materials - The materials used for extensions should closely match the existing materials in terms of type, colour, texture and method of construction. This is especially the case where the original dwelling is constructed of local stone. Where this is not possible, the relationship of the extension to the original dwelling should be reflected in the design. Detail - A detail can be defined as the junction between one building material and another. Between a roof and a wall, a house may have overhanging or flush eaves. Between a window and a wall, window heads and sills may be expressed in brick, stone or timber. Details should match the method of construction and, where possible, match those of the existing house. Types of extension Porches Although in many cases planning permission may not be required for porches, they should not be over dominant, and the design should reflect the criteria applicable for all extensions. Where a dwelling has a small front garden and the construction of a porch requires planning permission by virtue of its proximity to the highway, the floor space of the porch should be no more than 3 square metres and should project no more than 1.5m from the main front face of the dwelling. Front extensions The design and scale of extensions forward of a front wall of a house, and their distance from the pavement, are of paramount importance to the character of a residential area, which may be adversely affected by poor design. Front extensions where the house is set back from the pavement, or is well screened, would be considered more appropriate. Where possible, a reasonable distance between windows of habitable rooms, should be maintained. Side extensions (Fig. 1 & 2) Side extensions are usually prominent in the street scene and can have important implications for neighbours. Two storey side extensions should be set back from the front wall to avoid a terracing effect. The rear projection should accord with the requirements for rear extensions. Windows should not lead to over looking neighbouring dwellings or those on the opposite side of the road, and there must be no obstruction to highway sight lines, especially in the case of extensions on corner plots. 4

6 Fig 1 Unacceptable Fig 2 Acceptable Rear extensions Rear extensions are usually partially hidden and therefore have less of an impact on the street Semi Detached Property: Single Storey scene. However, they should still be appropriately designed so as to be in keeping with the character of the 45 o original dwelling and the surrounding area. They should not overlook, overdominate, or overshadow the adjoining property, and must leave adequate usable private garden space. Where } possible, the distance from the To extension to the front or rear of the nearest neighbouring dwelling should be 2. Single storey extensions to both semidetached and terraced properties should normally be designed with a rear projection of not more than 3.0m (Diagrams 1, 2 & 3). In cases where there are existing outbuildings projecting more than 3.0m and which are to be demolished and replaced with a new 5 Diagram 1 No 6 No 8 a maximum of 3m

7 single storey extension, consideration will be given to proposals exceeding 3.0m but which project no more than the existing outbuildings. Conservatories are usually to the rear, and therefore tend to fall under the requirements for single storey rear extensions. Terraced Property: Single Storey 45 o 45 o }To a maximum of 3m No 1 No 3 No 5 Diagram 2 45 o Terraced Property - (With Offshot). Single Storey & Two Storey To a maximum of 3m } To a maximum of 3m } No 1 No 3 No 5 No 7 No 9 No 11 Diagram 3 6

8 Individual two storey extensions (Diagrams 4, 5 & 6) which project more than 3.0m, would have to be set in from the boundary by 1.0m for each metre in excess of 3m. Two storey extensions will be looked at more stringently in terms of over looking, over dominance, and over shadowing. Semi Detached Property: Two Storey Terraced Property: Two Storey 45 o 45 o 45 o 2m 2m } To a maximum of 3m 2m 2m } To a maximum of 3m No 10 No 12 No 1 No 3 No 5 Diagram 4 Diagram 5 In the case of detached properties there is often more scope to consider larger rear extensions before they impinge on the amenity of neighbouring properties, simply because of the increased distance between properties. However, extensions will generally not be permitted where they are so large that they would encroach into the 45o exclusion zone. This is measured from the centre of the closest window to any habitable room (i.e. lounge, bedroom, kitchen) in the rear elevation of the adjacent dwelling (Diagram 6). Detached Property: Single and Two Storey 45 o No 1 No 2 Diagram 6 7

9 Dormers (Fig. 3, 4 & 5) Large dormers are undesirable, especially at the front of the dwelling. Several small dormers will usually be more acceptable. When considering the design of dormers, the main roof of the dwelling house should continue to dominate, therefore the dormer will normally have to be set down from the ridge of the main roof, be set in from the sides, and be set well back from the eaves. Generally, where possible, dormers should have a pitched roof to match the existing, especially at the front. Fig 3 Unacceptable Fig 4 Unacceptable Fig 5 Acceptable 8

10 Building Regulations Even in cases where planning permission is not required, you may need to obtain Building Regulation approval for your proposals. For further information, you should telephone (01302) and ask to speak to a Building Control Surveyor, stating the area where you live. Listed Buildings/Conservation Areas If your property is a Listed Building or is within a Conservation Area, you may require special consent for your proposals. Listed Building Consent is always required for an extension to a Listed Building. For further information, you should telephone (01302) /4922/4946/4950 and ask to speak to a Design and Conservation Officer, stating the area where you live. Trees and hedgerows If your proposals involve the removal of a tree or hedgerow, you may require special consent. For further information you should telephone (01302) and ask to speak to an arboriculturalist. 9

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12 For more information or general advice Customer Care Officers Policy, Performance & Enforcement Section Doncaster Metropolitan Borough Council Directorate of Development 2nd Floor, Danum House, St. Sepulchre Gate, Doncaster, DN1 1UB. Telephone: Fax: Issue date: August Adopted 20th July Designed by InHouse Graphics MM Printed by InPress