Property Extension Guide

As with all development the first thing to check is whether your project requires Planning permission. For guidance please refer to our link to the Permitted Development Guide.

If your project does require Planning Permission the following points should be considered. Please note: The points listed below are not exhaustive and are only intended to give you an idea of what may be possible when considering an extension. Please feel free to contact us to discuss the feasibility of your ideas before proceeding further.

You live in an area with special designation e.g. Area of outstanding natural beauty, Green belt, National Park, Conservation area

Your planning application will come under greater scrutiny than is usual and will need to follow specific Planning Policy Guidance. The visual and physical impact on the open and undeveloped character of their surroundings will be judged, particularly in green belt areas. Design, types of materials and visual prominence and traditional local architecture will be valued. However as with extensions to listed buildings, conservation does not mean preservation and some change is accepted and this designation is not a barrier to development. A very carefully thought out design is critical.

Precedent

Whilst all Planning applications are supposed to be considered individually and without prejudice, Planning authorities do attempt to be consistent. It would be unreasonable if two very similar proposals received different decisions.

Trees

If the proposals are likely to affect a tree that has a Tree Preservation Order (TPO) specialist advice from an Aboricultural expert will be required. Felling preserved trees may be acceptable if the tree is in decaying state but more often the Planners will want to see the Tree protected. Specialist advice may be needed where building close to preserved trees to ensure their safety e.g. root protection measures in the construction.

Overlooking

More of an issue with closely spaced houses. Overlooking can be caused by balconies, roof gardens or first floor conservatories. Windows that cause overlooking will not be permitted. First floor windows on the side of houses are restricted unless they are bathroom / WC windows with obscure glazing. However if there are no properties close by that could be affected this can be open to relaxation.

Overshadowing

The proposals should not have an over detrimental effect on the amount of daylight your neighbouring properties currently enjoy. Check on the line of movement of the sun and how this will have an impact. The size of the extension can thus be determined on its orientation.

There is also a rule known as the 45 degree rule. To comply with this rule an extension should not extend beyond a line drawn at an angle of 45 degrees from the nearest edge of the nearest window of the neighbouring house, excluding such things as a bathroom, utility room or landing windows. For one or two storey extensions the line should be drawn from the nearest ground floor or first floor window.

Oppressiveness

The proposals should not have an overbearing effect on a neighbour and create a poor aspect from their windows. Good design advice is critical.

Good design and character of the area

A very subjective matter indeed. Just because an extension is contemporary and different from the rest of the house does not mean it will be refused. However where the Planners feel that no attempt has been made to respect the character of an existing building or its surroundings this will be deemed as "bad design". A good deal of Architectural skill is required.

Extensions to houses in open countryside

The good news is that the restrictions applicable in built up areas i.e. overlooking and overshadowing do not apply. However this does not mean that the maximum size of extension is dependent on the amount of land available. Planning policies are in place to protect the attractive appearance of rural properties. Therefore a design that fits into the context of the surroundings is critical to gaining Planning approval.

Parking and access

The property after having an extension built should have adequate off road parking space. This differs in built up areas where the amount of required car parking space within the property boundary can be much less or even none at all. This is especially in town centre areas where access to public transport is easy so therefore reliance on a car can be minimal. Local Planning policy will dictate how many extra bedrooms will necessitate additional car parking spaces. This you will need to consider.