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Extension Specialists

Consevatories and planning permission

A guide from the 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 their home as opposed to moving because it's more cost effective. The most common home improvement is either a conservatory, extension or a loft conversion built onto our homes in balance with our disposable income.

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:

Detached Properties: You are allowed to develop up to 70m3 15% of the total volume of the dwelling whichever is greater. However, this is a combination of the total amount of extensions, i.e. is you have had an extension of 40m3 and require a conservatory of 35m3 this would total 75m3 and planning permission would be required. If the total is less than 70m3, 15% of the volume of the dwelling, planning permission may not be required.

Semi-Detached Properties:The same as detached properties, you are allowed to develop up to 70m3.

Terraced or End of Terrace Properties:Same as detached and semi-detached, but only 50m3 or 10%, whichever is the greater, is allowed to be developed.

Flats or Maisonettes:This type of property has no permitted development rights and in all cases planning permission will apply, there are no exceptions.

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

We have listed some additional information and conditions that will 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 timber conservatory with a glass roof.
  • Where a conservatory is 20m or less from a road or public right of way.

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.

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, you have proof that you have complied.

However, we strongly recommend, if in doubt always ask your local planning officer. You will find they are always very helpful and they will give you the correct advice so no mistakes are made.