Extension Planning Permission

House Extension Planning Permission

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Do I Need House Extension Planning Permission?

Whether you need a house extension planning permission is probably the question at the top of your list.

Many factors can influence house extension planning permission, but the good news is that house extensions are classed as Permitted Development, and as such, house extension planning permission will NOT be required, subject to the following conditions. 

  • No more than half the area of land around the "original house" can be covered by an extension.
  • No extension must sit forward of the principal elevation of your home or the side elevation if fronting a highway.
  • Your house extension must not be higher than the highest part of the existing roof.
  • A single-storey rear extension must not extend beyond the rear wall of the original house by more than three metres if an attached house (such as a terraced or semi-detached) or by four metres if a detached house.
  • (regarding the point above about house extension planning permission, increased limits of 4m and 8m, respectively, apply up to 30th May 2019 with regard to designated land and sites of special scientific interest. (subject to the prior notification of the proposal to the Local Planning Authority and the implementation of a neighbour consultation scheme. If objections are received, the proposal might not be allowed.)
  • The maximum height of a single-storey rear extension on your home must be no more than four metres, or house extension planning permission will apply.
  • Extensions of more than one storey must not extend beyond the rear wall of the original house by more than three metres.
  • There is a maximum eaves height of three metres for a house extension that sits within two metres of the boundary, or extension planning permission will apply.
  • The maximum eaves and ridge height of any extension must be no higher than that of the existing house.
  • If you want to add a house extension to the side of your property, this must be a single storey with a maximum height of four metres and a width no more than half that of the original house.
  • For two-storey extensions, rear and side house extensions must not sit closer than seven metres to the rear boundary.
  • If your extension is higher than one storey, the roof pitch must match that of the existing house.
  • Any materials used in the building of your house extension must be similar in appearance to the existing house – e.g. red brick, render.
  • No verandas, balconies or raised platforms.
  • Any windows on the upper floor of an extension that is side facing must have obscure glazing, and any opening must be at least 1.7m above the floor.
  • On designated land, there is no permitted development for rear extensions of more than one storey.
  • On designated land, no cladding of the exterior of an extension is permitted, or house extension planning permission will apply.
  • On designated land, side extension planning permission is not allowed. 

If you wish to find more information about these detailed aspects of house extension planning permission, visit the Planning Portal website.

House Extension Planning Permission

House Extension Planning Permission FAQs

What are the reasons I might need a house extension planning permission?

Take a look at the list above, which explains the criteria you must meet in order for your house extension to qualify for permitted development and NOT need to go through the extension planning permission process. Your local Planning office will be able to advise you fully, but there are various reasons why you may need house extension planning permission, such as if you have an external finish on your extension that differs from your home (e.g. a red brick home and a rendered extension). 

If you want to check on any of the criteria for house extension planning permission, get in touch with your local council’s planning department. Alternatively, if you have already appointed an Ultraframe Ultra Installer, ask them to complete the processes of your house extension planning permission on your behalf.

How do I go about getting house extension planning permission?

If the house extension you’re adding to your home does not meet the above criteria, it will either not be permitted or will require extension planning permission.

If you require house extension planning permission, then you will need to contact your local Planning Office. You will then be appointed your own Planning Officer or Building Control Surveyor, and they will be your point of contact for any house extension planning permission questions. Alternatively, if you are having your house extension project carried out by an Ultraframe Ultra Installer, they will take care of this for you.

How can a Planning Officer or Building Control Surveyor help with extension planning permission?

They will advise on any changes to your project that are needed to ensure that your house extension is planning permission compliant and will visit your project at agreed stages to sign off the work being carried out.

If you have any questions about extension planning permission, contact your Planning Officer, as they will know all of the details of your project and be able to help.

Can my installer help me with house extension planning permission?

If you have chosen an Ultraframe Ultra Installer to carry out your extension project, they will be able to take care of the house extension planning permission process for you – taking away the hassle and leaving you to enjoy other aspects of your extension project, such as choosing your furnishings and accessories. House extension planning permission doesn’t have to be a worry - your Ultra Installer can help.

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