Do You Need Planning Permission?

Some house extensions may fall within permitted-development rules, while others will require a planning application.
 

The correct route will depend on the property and the proposal.
 

Important considerations can include:
 

• the depth and height of the extension;

• whether it is single-storey or double-storey;

• the position of the extension;

• the type of property;

• previous extensions;

• whether the property is a house, flat or maisonette;

• whether the property is listed;

• whether the property is within a conservation area;

• whether additional local planning controls apply; and

• the effect on neighbouring properties.
   

Do not assume that an extension will automatically be permitted simply because a neighbour has completed similar work.
 

The planning history, property type and design details may be different.

 

Conservation Areas and Period Properties

Greenwich includes many attractive period streets and areas with a strong architectural character.
 

Where a property is within a conservation area or affected by additional planning controls, the design may need more careful consideration.
 

Materials, roof design, glazing proportions, the relationship with the original building and the effect on the surrounding area can all become more important.
 

This does not mean that an extension is impossible.
 

It means that the design should be considered properly and that the planning route should be checked before construction begins.

 

Planning Permission and Building Regulations Are Different

Planning permission considers whether the extension is acceptable in principle.
 

Building Regulations deal with how the extension is designed and constructed, including foundations, structure, insulation, drainage, ventilation and fire safety.
 

Most extensions will need Building Regulations approval even where planning permission is not required.
 

You may also need structural calculations, particularly where walls are being removed, steel beams are required or the rear of the property is being opened up to create a larger kitchen-diner.

 

Party Wall Considerations

Depending on the position of your extension and the proposed construction work, the Party Wall etc. Act 1996 may apply.
 

This can be relevant where you are:
 

• excavating close to a neighbouring property;

• building close to or directly against a boundary;

• working on an existing shared wall;

• inserting structural beams into a party wall; or

• carrying out works that affect neighbouring structures.
   

Party-wall matters should be considered early enough to avoid unnecessary delays before construction.

 

Glazing, Rooflights and Garden Access

The success of an extension often depends on the way natural light is handled.
 

A poorly considered extension can make the centre of the original house feel darker. A well-designed extension can create a brighter and more enjoyable space.
 

Options may include:
 

• sliding doors;

• bifold doors;

• fixed glazed panels;

• steel-look doors;

• rooflights;

• roof lanterns;

• clerestory windows; and

• internal glazed doors.
   

The best arrangement will depend on the room layout, garden, orientation and the way you plan to use the space.

 

Preparing Before You Ask Builders to Quote

It is usually better to obtain clear design drawings before requesting detailed builder quotations.
 

A builder needs enough information to understand what is proposed.
 

The drawings should normally identify:
 

• the size and shape of the extension;

• the internal layout;

• wall removals;

• door and window openings;

• roof form;

• drainage considerations;

• structural requirements;

• the general specification; and

• any important site constraints.
   

Without suitable drawings, you may receive quotations that are difficult to compare because each builder has interpreted the project differently.

 

Comparing Builder Quotations

Do not select a builder on price alone.
 

A lower quotation may omit important elements or allow unrealistic provisional sums.
 

Check whether the quotation includes:
 

• demolition;

• excavation and foundations;

• drainage work;

• brickwork and blockwork;

• structural steelwork;

• roofing;

• insulation;

• plastering;

• electrics;

• plumbing and heating;

• doors and windows;

• kitchen installation;

• flooring;

• decorating;

• waste removal;

• Building Control inspections; and

• VAT where applicable.
   

A clear scope of work will help you compare quotations more fairly and reduce the risk of unexpected extras later.

 

Professionals You May Need

Depending on the project, you may need support from:
 

• architectural designers;

• planning consultants;

• Building Regulations designers;

• structural engineers;

• Building Control professionals or registered approvers;

• party-wall surveyors;

• builders;

• glazing and door specialists;

• kitchen suppliers;

• electricians;

• plumbers;

• drainage contractors; and

• project managers.
   

Some homeowners prefer to appoint one main contractor to coordinate the works.
 

Others obtain separate quotations for selected services to maintain more control over the specification and budget.

 

Extensions Across Greenwich and the Surrounding Areas

APN Extensions can help homeowners exploring projects across the Royal Borough of Greenwich and nearby areas, including:
 

• Greenwich;

• East Greenwich;

• West Greenwich;

• Blackheath;

• Charlton;

• Kidbrooke;

• Eltham;

• Woolwich;

• Plumstead;

• Abbey Wood;

• Thamesmead;

• Lee;

• Hither Green; and

• surrounding parts of south-east London.
   

Every property should be reviewed on its own merits.
 

The right solution for a Victorian terrace in Greenwich may be very different from the best option for a semi-detached house in Eltham or a modern family home in Kidbrooke.

 

Planning a house extension in Greenwich?

Tell us about your property, the space you need and the type of extension you are considering.

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Where appropriate, APN Extensions may introduce you to relevant independent professionals, consultants and service providers who can help you move the project forward.

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You are under no obligation to appoint any provider introduced through APN.