Side House Extension, Rear House Extension, Rear Kitchen Extensions

Single Storey Rear Extensions to Houses

You can normally build single storey, full-width rear extensions to a depth of 4m for detached properties or 3m for other types of houses without planning permission. Single storey extensions are restricted to a height of 4m. If it is within 2m of a boundary the height of the eaves (if it has them), it cannot exceed 3m.

Multi-storey Rear Extensions to Houses

Extensions of more than one storey cannot be built if:

there is less than 7m between the extension and the rear boundary;
the property is in a conservation area.

If one or both of these of true then you will need to either apply for planning permission or only build a single storey.

If a multi-storey extension is allowed the only restriction to the number of storeys is the height of the existing house, which cannot be exceeded. As well as the overall height, the eaves on the extension (if it has any) cannot be higher than those of the existing house or 3m for the parts within 2m of the boundary.

Extensions of more than one storey are restricted to a depth of 3m for all houses.

Restrictions that Apply to Both

There is no longer any restriction for rear elevations that face the highway, unless the rare circumstance has occurred where it has been decided that the back of your house is the principal elevation. Kingston uses the following definition to decide which side of the house is the principal elevation: “The elevation that is designed to be the main elevation of the property (which will generally front a highway) and includes the most architectural detail (for example gable or bay window details or decorative porches).” Normally this will be what everyone agrees is the front, but if your house is at an angle to the road, on a corner, backs onto a road or if you are at all unsure you should check with the planning department which side of your house forms the principal elevation.

The extension must also conform to the following rules:

If the rear of the house is stepped, then the profile of the existing building must be retained.
The exterior materials used must be of a similar appearance to the existing building (not conservatories).
Any side facing veluxs, dormers or upper-floor windows must be obscure-glazed, and non-opening “unless the parts of the window which can be opened are more than 1.7 metres above the floor of the room in which the window is installed”
Where the extension has more than one storey, the pitch of its roof must, “so far as practicable”, match the roof pitch of the original house.
If your house is in a conservation area you cannot clad any part of the exterior of the dwellinghouse with stone, artificial stone, pebble dash, render, timber, plastic or tiles without requiring planning permission.

Flats, Maisonettes and Shops

If your property is a flat or maisonette (including those converted from houses) or a commercial property, such as a shop or public house you will need to apply for planning permission.

Listed Buildings

If you live in a listed building, you will need listed building consent for any significant works whether internal or external or in the grounds (curtilage) even if you do not require planning permission.
Question: Several years ago my neighbour built an extension at the back of his property. The wall of the extension comes within a couple of feet of my boundary fence. Do you think this may affect the value of my house? I don’t think he got planning permission, so is it true that after a while the structure becomes legal anyway?

Answer: It is not possible for me to comment on the possible effect of your neighbour’s extension on saleability. You will need to speak to a reputable local estate agent or qualified surveyor. Such extensions are not uncommon.

There are three things that the extension should probably have complied with:

1. The Party Wall Act
This requires prior notice to a neighbour of all structures affecting the boundary structures and/or excavations within specified distances of an existing boundary structure. Unfortunately, the Act does not create a specific right of action where the requisite notice is not served.

2. Planning Acts
Unless the structure was permitted because of its size, planning consent would have been required. After four years, however, the council loses its right to take enforcement action.

3. Building regulations
Any extension, unless an exempted conservatory, must comply with building regulations.

New Planning Permission rules

Planning Permission

This guidance reflects temporary increases to the size limits for single-storey rear extensions that must be completed by 30 May 2019, and the associated neighbour consultation scheme.

An extension or addition to your house is considered to be 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* 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.

* The term “original house” means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.

* Designated land includes conservation areas, national parks and the Broads, Areas of Outstanding Natural Beauty, and World Heritage Sites.

Kitchen extensions with skylights

kitchen extension open plan skylights
Kitchen extension open plan skylights

L shaped kitchen extension skylights roof lights
L shaped kitchen extension skylights roof lights

skylights kitchen extension
Skylights kitchen extension

electric roof windows
Electric roof windows

roof windows kitchen extension
Masive RSJs beam structural works

conservation area listed building electric windows
Conservation area listed building electric windows

roof lanter
Roof lantern

maisonette roof lights
Maisonette roof lights

roof window flat roof fibreglass
Velux roof window flat roof fibreglass

listed building roof lights
Grade 2 listed building roof lights

asphalt flat roof window
Asphalt flat roof window

Velux roof window
Velux roof window

roof lantern lead roofing
Roof lantern lead roofing

flat roof skylight
Flat roof skylight

extension roof light
Extension roof light