Single Storey Extension

Rear and side extensions are a great way to add living space to your home. From eye catching feature rooms to the more practical functional needs. They can create beautiful open plan kitchens with large bi fold doors letting the garden and light in. More modest sized extensions can enhance the rooms you already have and work well with internal alterations. Toilet and utility spaces can allow better comfort and get the noisy washing machine out the living areas.

Single storey extension design, planning and building regs in York
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single extension drawings in york


Our York based architectural design professionals will talk to you in depth about your needs. Every design needs to come from what you want to gain, can be built and passed by both planning and building control. Your budget will also come into the equation along with on site issues. We will perform a thorough walk over survey before sitting with you to advise.
Potential issues on site should be established such as shared boundaries, party walls, sewers, is it a listed building or in a conservation area?


Once the size and layout has been determined around the practical requirements such as access, integration, impact on existing spaces. You don’t want to end up with dark unusable or impractical spaces or corridor effect. With the size and layout, we will then explore roof options, tiled mono pitch, dual or ridged, hipped or flat roofs. Then we add the finishing touches with you discussing and displaying options around glazing and the important wow factors. We keep up to date with trends and new material finishes, plus cheaper alternatives that have similar effects.

CK Architectural York - Single Storey Extensions
CK Architectural York - Single Storey Extensions
CK Architectural York - Single Storey Extensions

Most single storey extensions can be built under permitted development, see guide below. We shall give you the necessary advice and where necessary make permitted development enquiries.

Here at CK Architectural York we shall ensure we know exactly what is legally required to be in place before you begin any building. Our clear planning application drawings present your design with necessary scales, site maps, etc to validate the application. We will check the design against the planning guidance such as over development, impact on street scene, right of light, over shadowing, loss of amenity and outlook, massing/dominance, loss of privacy, etc.

Our detailed building regulations plans and specification will include the necessary detail such as structure, passage of sound, disabled access, drainage, resistance to moisture, collision, impact, heat loss, ventilation, light, emergency escape and much more. Most alterations to your home will require a building certificate from a building control body, either local authority or private building inspector. Once the design and planning has been approved you will then need a detailed set of drawings. These drawing can be used for gaining quotation and will be checked against as the building is inspected. Our specification demonstrates the new extension can and will be built in accordance with the building regulations approved documents. These building regulations drawings will then be submitted for a full plan check, amended if necessary and once approved they will be the standard that is built to and inspection against. drawings will have used when the building control officer inspects the build to ensure the builder is carrying out the works correctly.

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single storey extension york


An extension or addition to your house is permitted development, not requiring an application for planning permission, subject to the following limits and conditions:

No more than half the area of land around the “original house” would be covered by additions or other buildings.

No extension forward of the principal elevation or side elevation fronting a highway.

No extension to be higher than the highest part of the roof.

Single-storey rear extension must not extend beyond the rear wall of the original house size by more than three metres if an attached house or by four metres if a detached house.

In addition, outside Article 2(3) designated land* and Sites of Special Scientific Interest the limit is increased to 6m if an attached house and 8m if a detached house until 30 May 2019.

These increased limits (between 3m and 6m and between 4m and 8m respectively) are subject to the prior notification of the proposal to the Local Planning Authority and the implementation of a neighbour consultation scheme. If objections are received, the proposal might not be allowed.

Maximum height of a single-storey rear extension of four metres.

Extensions of more than one storey must not extend beyond the rear wall of the original house* by more than three metres.

Maximum eaves height of an extension within two metres of the boundary of three metres.

Maximum eaves and ridge height of extension no higher than existing house.

Side extensions to be single storey with maximum height of four metres and width no more than half that of the original house.

Two-storey extensions no closer than seven metres to rear boundary.

Roof pitch of extensions higher than one storey to match existing house.

Materials to be similar in appearance to the existing house.

No verandas, balconies or raised platforms.

Upper-floor, side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor.

On designated land* no permitted development for rear extensions of more than one storey.

On designated land no cladding of the exterior.

On designated land no side extensions.

CK Architectural York - Single Storey Extensions
CK Architectural York - Single Storey Extensions
CK Architectural York - Single Storey Extensions


When choosing your builder Choose someone with lots of specific experience, choose someone you’d feel comfortable working with and talking to about concerns. Ask where they are based, Be clear about your timescale expectations and specific finishes. Quotations should be clear and easy to read with reference to our detailed approved building regulations drawings. Ask who will be doing the work, will they be sub-contracting and who is responsible. Make sure you know when you need to pay check their payment structure and be comfortable with it. Don’t always go with the references they give you, it’s not hard to find out where else they may have been working.

We try to add as much construction details possible but some assumptions must be made and certain area investigated before moving forward. Make sure you to remedy them. We offer help throughout for both you and the builder, we will come to site if help is required.

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