Appeal 3358024

The appeal is allowed and planning permission is granted for the erection of single storey extension and alterations following demolition of existing outbuilding at [site address] , Cranleigh, Surrey, [postcode] in accordance with the terms of the application, [name]/2024/01555, subject to the following conditions:

The development hereby permitted shall begin not later than three years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the drawing nos P.M.000 [name], P.M.100 [name], P.M.200 [name], P.M.201 [name], P.M.202 [name], P.M.203 [name], P.M.300 [name], P.M.301 [name], P.M.400 [name], P.M.500 [name], P.M.501 [name], P.M.502 [name], P.M.503 [name], P.M.600 [name] and P.M.601 [name].

The external materials of the extension hereby permitted shall match those used in the existing dwelling.

Prior to the occupation of the development hereby permitted, the building to be demolished shown on drawing nos P.M.100 [name] and P.M.400 [name] shall be demolished and all demolition material removed.

In the interest of accuracy, the description of development in the banner heading above is based on the decision notice and the appeal form.

The main issue is whether the proposal would be inappropriate development in the Green Belt for the purposes of the National Planning Policy Framework (the ‘Framework’) and development plan policy.

The appeal property is a detached chalet-style dwelling positioned to the west of [site address] , accessed through the adjoining garden centre and associated commercial yard. It occupies a large, landscaped plot containing mature boundary vegetation and detached outbuildings. The property lies outside, but close to, the defined settlement boundary of Cranleigh, within a cluster of substantial dwellings and commercial buildings on the settlement’s northern edge. Although within the designated Metropolitan Green Belt, it forms part of a developed corridor rather than an isolated rural location.

The proposal is for a single-storey side extension to form a utility and boot room, measuring approximately 4.1m by 5.3m, with a hipped roof. Exception (c) of Paragraph 154 of the Framework states that the extension or alteration of a building is not inappropriate development in the Green Belt provided that it does not result in disproportionate additions over and above the size of the original building. There is no definition of “disproportionate” in national policy and it does not set a specific numerical threshold for assessing proportionality. Instead, the Framework refers to ‘size’. This can, quite reasonably, refer to volume, height, external dimensions, footprint, floorspace or visual perception. The assessment is therefore a matter of planning judgment, based on the overall scale, bulk, massing and visual appearance of the extension relative to the original building.

Policy RE2 of Part 1 of the Waverley Local Plan (2018) 1 is consistent with this national approach, and Policy DM14 of Part 2 of the Local Plan (2023) 2 (the ‘Local Plan’) advises that extensions outside settlement boundaries will normally be considered disproportionate where cumulative floorspace increases by more than 40%. However, the supporting explanatory notes to the policy make clear that this percentage is a guideline, and that each case must be considered on its own merits having regard to how isolated a site is and the scale and mass of the original building. Flexibility may therefore be appropriate where a dwelling lies outside but is visually well related to a settlement boundary or forms part of a village.

In this case, the appeal site lies just beyond the northern edge of Cranleigh’s defined settlement boundary but forms part of a clear transition between the built-up area and the wider countryside. Development continues along [site address] in the form of substantial houses and the large garden-centre complex, which together create a developed frontage extending north of the settlement envelope. The access road serving the appeal property provides entry to a small cluster of detached dwellings behind the garden centre. In this context, the site appears visually and functionally connected to Cranleigh rather than isolated within open countryside. The site’s close relationship with Cranleigh supports a flexible application of the 40% guideline.

The Council calculates that the existing and proposed extensions together would represent a cumulative floorspace increase of approximately 74 percent over that of the original dwelling, exceeding the 40 percent threshold referred to in Policy DM14. Notwithstanding this, the extension would be modest in footprint, single-storey, and clearly subservient in height, sitting well below the eaves and ridge of the main house. It would not project beyond the existing front or rear elevations, 1 Waverley Borough Council, Local Plan Part 1: [name] and Sites, adopted February 2018. 2 Waverley Borough Council, Local Plan Part 2: Site Allocations and Development Management Policies, adopted March 2023. and its matching materials and hipped roof profile would ensure it integrates with the existing built form without disrupting the proportions of the principal elevations.

Taking these factors together, the proposal would appear as a small, ancillary addition that preserves the overall balance and character of the house. The modest form and discreet siting mean the original chalet proportions would remain clearly legible. The proposed addition would be read against existing built form and would not introduce a perceptibly larger or bulkier structure. The limited scale of development would therefore not amount to a disproportionate addition in physical or visual terms.

Accordingly, the proposal would not constitute a disproportionate addition and would accord with exception (c) of paragraph 154 of the Framework. For these reasons, I conclude that the proposal would not be inappropriate development in the Green Belt. It would accord with Policies RE2 and DM14 of the Waverley Local Plan and with the Framework insofar as they seek to ensure that proposals for extensions in the Green Belt are appropriately scaled.

Impact on openness is implicitly taken into account in the exceptions outlined in paragraph 154 unless there is a specific requirement to consider the actual effect on openness. In exception (c), the effect of the development on openness is not expressly stated as a determinative factor in gauging inappropriateness. Consequently, as I have found the proposal would not be inappropriate development, there is no requirement to assess the impact of the development on the openness of the Green Belt.

For the avoidance of doubt and in the interests of certainty I have imposed the standard commencement condition and a condition requiring compliance with the submitted plans. To protect the character and appearance of the appeal dwelling and surrounding area, I have imposed a condition requiring the external materials of the extension match those used in the existing dwelling.

Furthermore, the appellant indicated their intention to remove an existing outbuilding within the rear garden. To ensure its demolition, I have imposed a condition requiring it is demolished prior to the occupation of the development.

For the reasons given above the appeal should be allowed.