Policy information sourced from Redbridge Local Plan

LP31: Basement Development

For domestic and commercial properties, the Council will only support basement and subterranean development involving further excavation of land that:

  • Is wholly confned within the curtilage of the application property and designed to maintain and safeguard the structural stability of the application building and nearby buildings;
  • Does not comprise of more than one storey or be under an existing basement, subject to the fndings of a Basement Impact Assessment (BIA);
  • Does not extend into or underneath the rear garden, from the principal rear wall, to a depth of more than 50% of the garden, and to the front of the property to a depth of more than 30%;
  • Includes a sustainable urban drainage scheme, including 1m of permeable soil depth above any part of the basement beneath a garden;
  • Does not cause loss, damage or long term threat to trees of townscape or amenity value;
  • Ensures that any externally visible elements such as light wells, roof lights and fre escapes are sensitively designed and sited to avoid any harmful visual impact on neighbour or visual amenity;
  • Does not have an adverse impact on drainage, fooding from all sources, groundwater conditions and the structural stability of the host property or neighbouring properties.

The Council will only support developments that:

  • Do not cause harm to the built and natural environment and local amenity;
    • Do not result in fooding or ground instability; and
    • Do not threaten mature trees through changes to hydrological conditions or the severance of tree roots.
  • Includes a Basement Impact Assessment (BIA), appropriate to the scale of the proposal that assess geotechnical, structural engineering and hydrological impacts.

Implementation

The Council will make use of its preapplication service to engage developers ahead of submissions of planning applications for basement development or extensions;

The Council will encourage developers to undertake public engagement/neighbour notifcation ahead of planning application submissions; and

The Council will consider providing additional guidance related to basement development/extensions.

For more information please see the Local Plan