Extensions will permanently alter the appearance and character of a property. The low overall density of development on the Suburb means that in many cases some extension can be allowed without harm to the individual house or its neighbour hood. Rear ground floor extensions may be acceptable, but the impact on neighbouring properties will be carefully assessed. Front extensions are most unlikely to prove acceptable. Side extensions may close up the gaps between properties, creating continuous ‘terracing’ which destroys the open character of the layout and the carefully designed views between buildings.
We will consider the following points when assessing whether to accept a proposed extension:
- What is the proposal increase in ground floor area compared with the original?
There is a limit to the amount of extension which a house can accommodate without seriously harming the original design concept or intruding too much on the space between neighbouring houses. Small extensions that fall within an imaginary line continuing from the main roof slopes to ground level are preferred. The acceptability of larger extensions depends on the particular site and circumstances. All previous extensions are taken into consideration and although every application is considered individually, there will be sensitive cases where no extension or further extension can be permitted.
- Is the existing building part of a group?
In many parts of the Suburb the group aspect was emphasised with houses set around greens or culs-de-sac, or linked by garages or screen walls. The substantial alteration of one unit could destroy the balance and the harmony of the whole. Changes of this type will be considered very carefully and are likely to be refused if they would harm the group.
- Will the alterations or extensions affect or overlook neighbouring properties?
We strongly recommend that you discuss your proposals with immediate neighbours at the earliest stage. The Trust and Barnet Council notify your neighbours of applications. Development will be resisted where new windows to habitable rooms would significantly increase overlooking or if the building would dominate neighbouring properties. We will take into account all representations about overlooking or overshadowing before making a decision upon an application.
- Will the extensions be visible from the road or another public viewpoint and, in particular, will they encroach upon spaces between buildings, closing out distant views?
In general, any extensions should be to the rear of the property. We normally resist extensions that would intrude upon well established views, for example, two-storey side extensions or extensions above existing garages.
- Will the extension be in character?
For an extension to be acceptable in principle, it should be designed to harmonise with, and be inspired by, the original form and character of the house.
- Have any insensitive alterations already taken place?
Some properties were altered before the strict controls of today were in place. We would not accept previous insensitive and possibly unauthorised alterations as a justification for further unacceptable works. In line with good practice, improvement to any previous unsympathetic alterations should be included in a scheme of further change.
Indeed, in appropriate cases, the Trust may make consent for alterations or extensions conditional upon the removal existing insensitive features.
These points serve as guidelines, but it should be borne in mind hat all proposals are assessed on their individual merits and that there may be cases where extensions are considered unacceptable, even though they may appear to conform with these guidelines.
It is worth remembering that the rear of houses were as carefully designed as the front and can often be viewed by the public places such as footpaths. Consequently, lower standards of design are not acceptable at the rear.
The design of successful extensions requires a knowledge of the building type and a sensitive handling of scale and detail. Although the Trust Architect and Council Officers will offer informal advice, we advise you to employ an architect with knowledge and experience of this type of work. The architect’s drawings will form the basis for a decision on an application. Clear, concise and accurate information with attention to detail is essential. We strongly recommend that you retain professional involvement during construction. |
