Policy information sourced from the Hillingdon Local Plan: Part 1

Hillingdon - OL4 Green Belt - Replacement or Extension of Buildings

The local planning authority will only permit the replacement or extension of buildings within the green belt if:

  1. the development would not result in any disproportionate change in the bulk and character of the original building;
  2. the development would not significantly increase the built up appearance of the site;
  3. having regard to the character of the surrounding area the development would not injure the visual amenities of the green belt by reason of siting, materials, design, traffic or activities generated. 

For more information please see Appendix 5 of the Local Plan: Part 1