New Planning Rules for Home Improvements - October 2008

New regulations governing the construction of domestic extensions in England and Wales came in to force at the start of October 2008. The changes mean that most people planning to add space to their homes will not require planning permission.

Since the last property boom took off in 1995 the number of planning applications being submitted each year in the UK has more than doubled to 330,000; these new regulations are intended to reduce the workload on Local Planning Authorities.

The requirement for Building Regulation approval is unchanged by the new regulations. In addition, if the planned work will affect a shared wall, or involves excavating close to a boundary, it will probably be covered by The Party Wall etc. Act 1996.

Owners planning works which fall within the scope of the Act have an obligation to serve written notice on the adjoining owners.

The new regulations cover single and multi-story extensions as well as loft conversions. All new basement conversions will still require planning consent.

As before, further restrictions on all extensions will apply to properties within Conservation Areas and within the curtilage of listed buildings. If you are in any doubt the best advice is to contact your local planning office to discuss the proposals before commencing work.

Under the new regulations an extension will be considered a 'Permitted Development', and will not require planning consent, if it comes within set limits. The most significant of those limits are listed below.

Ground Based Extensions

Single storey rear extensions up to 4 metres deep may be added to detached properties, the measurement is taken from the original rear wall of the property. On semi-detached and terraced properties, and for all multi storey extensions, the maximum depth is reduced to 3 metres.

Extensions to the side of an existing property must be single storey only and no more than half the width of the original house.

All single storey extensions should be no more than 4 metres high and multi storey extensions no higher than the roofline of the existing property.

Loft Conversions

Restrictions on how much volume can be added to a roof space remain in place although the new, more generous, maximum allowances mean that a full width dormer can be added to most properties without permission. The volume allowance on attached houses is 40 cubic metres, increasing to 50 cubic metres on detached properties.

Dormers will not be permitted on elevations that face a highway or be allowed to extend above the ridge of the original roof. The changes do not place any additional restrictions on the raising of new side gables as part of a loft conversion. In the past planners were reluctant to grant permission for this type of change but the decision has now been taken out of their hands.


The new regulations have also tried to tackle a serious problem that has developed over the last few years; run off water from paved-over driveways.

In 2007 alone three billion pounds worth of damage was caused by flooding in the UK. Experts believe that of all the property damage that occurred, surface water run-off was a contributory factor in around two-thirds of cases.

To try and reduce the number of front gardens that are being paved over the Government has removed the requirement for planning consent where a homeowner intends to create a driveway covering an area of greater than 5 square metres; on condition that a permeable material is use. Acceptable materials include concrete block paving with gaps, porous asphalt or gravel and wheel track only concrete strips with 'soak-aways' between.

You can view full details of all the new regulations on the Government Planning Portal -

Article written by Justin Burns MRICS of Peter Barry Chartered Surveyors & Party Wall Consultants

England and Wales
England and Wales