Conservatories: A guide through the corridors of local authority’s conservatory planning requirements.

The fact is that home improvement is one of the largest growth areas in our economy today. Many people today are improving there home as opposed to moving because it’s cheaper. The most common home improvement are conservatories followed by extensions and loft conversions.

Therefore, to keep a firm rein on these developments; planning requirements are getting tighter to ensure that the type of home improvement is in keeping with the surrounding houses and neighbourhood. I am sure we all agree – “nobody would wish to live next to a monstrosity”.

Approximately 60% of conservatories built will require planning permission.

Under the present legislation you may not require planning permission providing you meet with the following conditions:

  • No more than 50% of the land which surrounds the “original house”* can be developed. If you require a conservatory that covers more than 50% planning permission is required.
  • If the proposed conservatory faces any road, planning permission will be required.
  • Maximum depth for a conservatory on a detached property is 4000 mm
  • Maximum depth for a conservatory on a semi deched property is 3000 mm
  • The maximum height of a conservatory is 4000 mm
  • Conservatories built to the side elevation of a property a maximum of 4000 mts high and no more than 50% that of the original house
  • At least 50% of area that will form the external boundary / edge of the conservatory must be glazed and 75% of the roof area to be covered with either glass or polycarbonate.(Building regulations)
  • All conservatories must be separated from the house by an external quality door, patio door or French doors. (Building regulations)

Conservatories on listed building, national parks, Broads Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites planning permission will be required.

* 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).

Even if you may not have had an extension built to the house, a previous title-holder may have done so.

The above mentioned only applies to extensions after the 1 July 1948.

We have listed some additional information and conditions which attract planning permission:

  • If you build within 2m of the boundary line and the highest point at that junction is 4m or more high.
  • If your conservatory covers more than 50% of the original garden.
  • If your planning development rights have been removed.
  • Grade II listed buildings. These may require a hardwood conservatory with a glass roof.
  • Where a conservatory is 20m or less from a road or public footpath.
    (see sketch A)
Conservatories Planning Permission Information

Sketch A: Irrespective of the size of the conservatory, should the distance between points A and B be less than 20m planning permission may be required.

Shaded Area may be any of the following:

  • Road
  • Highway
  • Motorway
  • Public Foot Path
  • Bridal Way
  • Access to another property
  • Access to other garage

Impact onto the Boundary Normally the local planning officer will be looking at the projection of the conservatory i.e. how far it will protrude into the garden, normally they are happy at about 3m projection from the original house. However, should the proposed conservatory extend more than 3m he may not look at it so favourably and ask for it to be reduced in size? The reason for this is so your neighbour does not have to look at a large brick wall more than 3m long. Hence the term impact onto the boundary.

Conservatories Planning Permission Information

To overcome this you may wish to include a facet to your conservatory which may help in some situations. (See sketch B) This should be done by your supplier as a matter of course.

Sketch B: You can see from this sketch that the total impact onto the boundary is 6m and you could expect the planning office to reject your application.

If planning permission is not required a letter of lawful development from the council is always a good item to obtain. So should you wish to sell your property in the future, your have proof that you have complied.