Permitted Developments

Certain types of building works can be carried out without applying for planning permission, subject to list of conditions and specified limits. Notably, the build still needs to comply with building regulations.

A Loft conversion is considered to be permitted development, not requiring planning permission subject to the following:

  • A volume allowance of 40 cubic meters and 50 cubic meters of additional roof space for terrace houses and semi-detached or detached houses respectively.
  • Materials to be similar in appearance to the existing property.
  • Balconies, verandas and external platforms are not permitted.
  • Side facing windows to be obscure double glazed.
  • Extension is not to exceed the height of the existing roof.
  • Roof enlargement cannot overhang the outer face of the wall of the wall of the original house.
  • Roof extensions (with the acceptation of hip to gables) to be set back at least 20cm from the original eaves.

An Extension is considered to be permitted development, not requiring planning permission subject to the following:

General conditions

  • No more than half of the are of land around the original house can be covered by additions to the existing property.
  • Materials to be similar in appearance to the existing property.

Single Storey Rear Extensions:

  • Terraced or semi detached houses can extend no more than 3 meters from the existing property rear wall.
  • Detached properties can extend no more than 4 meters from the existing property rear wall.
  • Single storey extensions cannot be higher than 4 meters.

Double Storey Rear Extensions:

  • Two storey extensions cannot be extended more than 3 meters from the existing property rear wall (this is applicable for all houses; terraced, semi detached and detached).
  • The extensions eaves must not be higher than the eaves of the existing house.
  • Two storey extensions cannot be within 7 meters of any boundary opposite the rear wall of the house. (This one may sound confusing. More simply if your rear garden is longer than10 meters you should not have a problem here).
  • The eaves height of a rear extension cannot exceed 3 meters if it is within 2 meters of an adjoining boundary.

Terraced and semi-detached properties rarely benefit from the permitted development rights due to the 2 meter boundary rule.

Double Storey extension Roof Design:

Under permitted development, a double storey extensions typically have a roof element of 10- 35 cubic meters. You must be aware that if you also plan to build a loft conversion, this space may take up a large volume of your allowance. If this is the case, many people opt for a fact roof so that the loft conversion capacity is not affected.

Side Extensions:

  • Side extensions must be less than half of the width of the existing property.
  • Only single storey side extensions are permitted development.

Conservatories fall under the same conditions and restrictions to those imposed for single storey extensions.

A Front Porch is generally the only front elevation to a property that can be built under permitted developments. Again, there are some regulations:

  • No part of the porch can exceed 3 meters in height.
  • It cannot be within 2 meters of any boundary.
  • The ground area cannot exceed 3 square meters (eg. 3 meters in length x 1 meter in width etc). Notably this is the external measurement of the porch, not the internal floor space.

Out-Buildings can also be a great way of adding extra space to your property without the need to go through planning permission, especially if you have a large plot or rear garden. Home gyms, offices or quiet work places, garage, storage units, sheds and in door play rooms are amongst the most common uses of out-buildings. Be aware that out-buildings should accommodate the property and they cannot be used as additional residential accommodation. The conditions and limits are as follows:

  • Out-Buildings cannot sit forward of the principle elevation.
  • The total area covered by additions to the property cannot exceed 50% of the total area covered by the main house.
  • Roof height must not exceed 2.5 meters when the building is within 2 meters of any boundary line.
  • Roof height cannot exceed 3 meters.

Internal Remodelling that does not involve increasing the footprint of the dwelling can be carried out under permitted development. Knock through works to create large open plan living areas have become extremely popular and may involve structural works which will need to comply with building regulations. This is also required when moving or adding doors or windows.

Standard Restrictions to Permitted Development Rights:

If your property is a flat, maisonette, lies in a conservation area, is less than 10 years old or the use of the property is being changed you will require planning permission regardless of the above conditions.

Should you be unsure whether your required build is considered permitted development, our team will more than happily provide advise and help you establish your rights as a home owner. In a lot of cases, our clients are pleasantly surprised by how much they are able to increase the size of their property without the need for planning permission.

For other types of constructions such as decking, basements, roof-lights, gates, walls and fences, swimming pools and vehicular access and more please do not hesitate to call for advise or a free consultation.

Call us: 0752 504 1120 or 0208 361 7458 (office)
TLC Planning and Design
33 East Barnet Road
New Barnet
Company number 10266155

Working in the London area, including
Barnet, Bounds Green, Camden, Chingford, Crouch End, Enfield, Hendon, Edgware, Finchley, Ilford, Leytonstone, Muswell Hill, Palmers Green, Southgate, Stoke Newington, Walthamstow, Winchmore Hill

Working in the Essex area, including
Brentwood, Buckhurst Hill, Chigwell, Church Langley, Dunmow, Epping, Harlow, Loughton, Ongar, Rayleigh, Romford, South Woodford, Wanstead, Woodford

Working in the Hertfordshire area, including
Bishops Stortford, Borehamwood, Broxbourne, Cheshunt, Hertford, Hoddesdon, Letchworth, Potters Bar, Radlett, Sawbridgeworth, St.Albans, Ware

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