Planning permission is not normally required. However, permission is required where you extend or alter the roof space and it exceeds specified limits and conditions. A loft conversion for your house is considered to be permitted development, not requiring an application for planning permission, subject to the following limits and conditions:
- A volume allowance of 40 cubic metres additional roof space for terraced houses*
- A volume allowance of 50 cubic metres additional roof space for detached and semi-detached houses*
- No extension beyond the plane of the existing roof slope of the principal elevation that fronts the highway
- No extension to be higher than the highest part of the roof
- Materials to be similar in appearance to the existing house
- No verandas, balconies or raised platforms
- Side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor
- Roof extensions not to be permitted development in designated areas**
- Roof extensions, apart from hip to gable ones, to be set back, as far as practicable, at least 20cm from the original eaves.
*Please note that any previous roof space additions must be included within the volume allowances listed above. Although you may not have created additional space a previous owner may have done so. The Rules governing flats and maisonettes are different from house and cannot be done under permitted development. There is an excellent guide provided by the Government planning portal which can be found by clicking on this link.
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.
- 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.
Please note that flat and maisonette will not come under permitted development and will require planning permission, you will also need the consent of your leaseholder There is an excellent pdf document provide by the Goverment Planning Portal that can be found at this link
You can extend your property under permitted development. However if you have already extended or converted your loft you will probably need to apply for permission. unless the floor area is 30 sq metres or less, its roof is of transparent material, its walls are of toughened safety glass and it not knocked thru to the main house. Where any wall, door or window separating the conservatory from the main building is removed and it is not replaced with a wall, door window; or the main buildings heating system is extended into the conservatory or porch - you will be required to submit a Building Regulation application showing how you intend to comply with the energy saving provisions of the Building Regulations.
A conservatory is classed as an extension, therefore planning permission will be required if any of the following apply:
- As a result of the works, more than 50% of the land surrounding the original house would be covered with buildings.
- The height of the part of the house enlarged, improved or altered exceeds the highest part of the roof of the existing house.
- The height of the eaves of the part of the house enlarged, improved or altered exceeds the height of the eaves of the existing house. (Highest eaves on the dwelling).
- The enlarged part of the house extends beyond a wall which:
- Fronts a highway and
- Forms either a principal (front) or side elevation of the original house.
- The enlarged part of the house would be located within 2m of the property boundary and the height of the eaves of the enlarged part exceeds 3m.
- The extension includes the construction of a veranda, balcony (not Juliet balconies) or raised platform (a raised platform is defined as anything more than 300mm above ground level – measured at the highest point). This will include decking and the 50% rule will also apply).
- The extension includes the installation, alteration or replacement of microwave antenna.
- The extension includes the installation, alteration or replacement of a chimney, flue or soil and vent pipe.
- The extension involves alteration to any part of the roof.
For Rear Conservatories
- On a detached house, the conservatory extends beyond the rear wall of the original house by more than 4m.
- For any other house, the conservatory extends beyond the rear wall of the original house by more than 3m.
- The conservatory exceeds 4m in height.
For Side Conservatories
- The conservatory exceeds 4m in height.
- The conservatory has more than one-storey.
- The conservatory has a width that is greater than half that of the original house.
In A Conservation Area Development Is Not Permitted If:
- It would consist or include the cladding of any part of the exterior of the house with stone, artificial stone, pebble dash, render, timber, plastic or tiles.
- The enlarged part of the house would extend beyond a wall forming a side elevation of the original house.
- The enlarged part of the house would have more than one-storey high and extend beyond the rear wall of the original house.
Development Is Permitted Subject To The Following Conditions:
- The materials of external construction should be of similar appearance to those of the existing dwelling (except in the case of conservatories).
- Any upper-floor windows in the wall or roof slope forming a side elevation of the dwelling shall be obscured-glazed (level 4 or 5 obscurity) and non-opening (unless the opener is more than 1.7m above the floor of the room in which the window is installed). (This relates to windows and roof lights in the side wall/roof slope of the original house)
- Where the enlarged part of the house has more than one-storey, the roof pitch of the enlarged part shall, so far as practicable, be the same as that of the original house
Most people realise that they may need approval for their proposed building work but they do not always understand the difference between building regulations and planning permission. Building Regulations and planning permission are separate pieces of legislation. It is likely that applicants will have to make applications for both Building Regulation consent and Town Planning Permission.
Building Regulations deal mainly with health and safety matters in the interest of the people who will use the building. In simple terms: Building Regulations are concerned with how a building is constructed with particular reference to:
- structural stability
- fire safety
- site preparation and resistance to moisture
- toxic substances
- sound resistance
- drainage and waste disposal
- heat producing appliances
- protection from falling, collision and impact
- conservation of fuel and power
- access and facilities for disabled people
- glazing safety
- electrical safety
These are legal requirements but provided that the correct technical standards are met the approval should be straightforward. The council's Building Control Officers deal with Building Regulation applications.
Planning permission deals with the use of land, the appearance of buildings, landscaping considerations, highway access and the impact that the development will have on the general environment. Officers of the council's Town Planning Services deal with planning applications and also listed buildings, conservation areas and tree preservation orders. If planning permission is required it may sometimes be wise to wait until that permission is granted before proceeding to submit a building regulation application
Rules governing outbuildings apply to sheds, greenhouses and garages as well as other ancillary garden buildings such as swimming pools, ponds, sauna cabins, kennels, enclosures (including tennis courts) and many other kinds of structure for a purpose incidental to the enjoyment of the dwellinghouse. Other rules relate to the installation of a satellite dish, the erection of a new dwelling or the erection or provision of fuel storage tanks. Under new regulations that came into effect on 1 October 2008 outbuildings are considered to be permitted development, not needing planning permission, subject to the following limits and conditions:
- No outbuilding on land forward of a wall forming the principal elevation.
- Outbuildings and garages to be single storey with maximum eaves height of 2.5 metres and maximum overall height of four metres with a dual pitched roof or three metres for any other roof.
- Maximum height of 2.5 metres in the case of a building, enclosure or container within two metres of a boundary of the curtilage of the dwellinghouse.
- No verandas, balconies or raised platforms.
- No more than half the area of land around the “original house”* would be covered by additions or other buildings.
- In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from house to be limited to 10 square metres.
- On designated land* buildings, enclosures, containers and pools at the side of properties will require planning permission.
- Within the curtilage of listed buildings any outbuilding will require planning permission.
*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 national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites.