A maximum extension space of 50m3 (30m3 in National Park Conservation areas) without Approval (or 10% if greater)
SEMI-DETACHED or DETACHED HOUSES
A maximum extension space of 70m3 (50m3 in National Park Conservation areas) without Approval (or 15% if greater)
In every case if the total extension space is greater than 115m3 regardless of other rules
In addition the following Guidelines ALSO apply and mean you probably require full Local Authority Planning Permission is your project falls into ANY of these categories
The conservatory would be nearer to any highway than the nearest part of the original house, unless there is 20 metres or more between your house (including the conservatory) and the highway. The term 'highway' includes roads, footpaths, bridleways and byways if there are public rights of way. We also read this as it does not apply if another property falls between you and the highway, even if the distance remains less than 20 metres! This exception also applies if the conservatory does not pass the existing building line (i.e. pass the end of your house - if the conservatory is installed to the rear of your house ending before your existing house ends, but the highway is to the side of your house)
More than half the area of land around the original house would be covered by additions or other buildings.
The conservatory is higher than the highest point of the roofline of the original house.
Any part of the conservatory comes within 2 metres of your boundary if it is more than 4 metres above the ground.
In the following cases, the volume of other buildings which belong to your house (such as garage or shed) will count against the volume allowances. In some cases, this can include buildings which were built at the same time as the house or existed on 1st July 1948
If an extension to your house comes within 5 metres of another building belonging to your house, the volume of that building counts against the allowance for additions and extensions.
Any building which has been added to your property and which is more than 10 cubic metres in volume and which is within 5 metres of your house is treated as an extension of the house and reduces the allowance for further extensions.
If your house is a listed building or is in a Conservation Area, an area of Outstanding Natural Beauty or the Broads then permission is more likely to be required as other restrictions may apply and extension space reduced
It is also worth noting that occasionally 'permitted development' rights may have been withdrawn from a property and any extension no matter how small needs permission. If you have any doubts at all, check with your local authority
NOTE: Original house size is as it was first built, or as it stood on 1st July 1948 if it was built before this time. If extensions have been constructed since, then they too count against the allowance.
HERONHURST can take away the worry of Planning Permission and can offer a COMPREHENSIVE PLANNING APPLICATION SERVICE to all our Conservatory customers