Single-storey rear extension at 10 Gade Bank, Croxley Green, Rickmansworth

What was proposed

The application sought part-retrospective permission for a built single-storey rear extension, with bi-folding doors, matching render and internal layout changes.

“Parking associated to the properties on Gade Bank is located on the opposite side of the access road serving this row of dwellings. The property has been put to use as a House of Multiple Occupation (“HMO”) (Use Class C4); however, the property is currently vacant following a Closure Order (see paragraph 8.1.7). Description of Proposed Development 3.1 This planning application seeks part-retrospective planning permission for a single storey rear extension.”

“The external appearance of the extension as built is white painted smooth render. It is now proposed for a brick-slip or render that matches the external appearance of the dwelling to be applied to the elevations of the extension. Clarification was sought from the applicant on the external appearance, and it has been confirmed that the extension would have a pebble-dash render exterior. The submitted drawings show that the extension would be rendered to match.”

Officer report

The site

The property is a two-storey semi-detached house beside the Grand Union Canal, woodland and school playing fields, within the Metropolitan Green Belt.

“Gade Bank is a short cul-de-sac, characterised by eight pairs of semi-detached dwellings built on a uniform building line in a single row. The application site is within a semi-rural location with the Grand Union Canal situated to the east of the site on the opposite side of Gade Bank. The rear of the site (to the west) is woodland covered by a Woodland Tree Protection Order (TPO790) which stretches the entire length of Gade Bank, with school playing fields beyond this.”

Officer report

Earlier applications and enforcement

An earlier retrospective application was refused over parking, neighbour amenity and design concerns, while an enforcement case for the unauthorised extension remained pending.

“Relevant Planning & Enforcement History 1.1 25/1330/RSP - Retrospective: Construction of single storey rear extension – Refused November 2025 for the following reason: R1 The single storey rear extension has resulted in an intensification of use of the site and a shortfall in parking to the detriment of neighbouring amenity and the character of the area.”

Officer report

Why officers supported it

Officers considered the extension proportionate in the Green Belt, suitably designed, acceptable for neighbours and not refused solely because of a small parking shortfall.

“The development would therefore not exceed the 40% guideline as set out in the SPG; and given the extension is located at the rear of the property and has a flat roof design the proposed development is not considered to be a disproportionate addition to the host property. As the proposed extension is not considered disproportionate to the original property, it is not inappropriate development within the Green Belt.”

“Application 25/1330/RSP was refused by Members at the November Planning Committee after Members raised concerns that the design of the extension, including two rear doors, and materials did not match the original dwelling house and therefore considered that the extension failed to respect and is harmful to the character and appearance of the host dwelling and area. This application has sought to overcome these concerns by amending the design of the extension.”

Officer report

Who spoke

A parish councillor and a local resident spoke against the application, raising concerns about HMO use, road repairs, noise and peaceful enjoyment.

What members discussed

Members treated noise, bathrooms and insulation as building control matters, while supporting the stated intention to return the property to a single dwelling.

“In discussion Committee Members noted that concerns about noise, placing of services such as bathrooms, and insulation were building control matters and not material planning considerations.”

“Whilst recognising that it was not a material planning consideration, Committee Members were supportive of the applicant’s stated intention to return the use of the property to a single dwelling house.”

Minutes

The vote and decision

Members voted eight for, none against and one abstention, granting part-retrospective planning permission subject to conditions.

“Councillor Drury moved, and Councillor Lloyd seconded, that part-retrospective planning permission be granted subject to conditions.”

“That part-retrospective planning permission be granted subject to conditions.”

Minutes

Conditions attached

The bi-folding doors and matching pebble-dash render must be completed within four months, with remaining works following the approved plans.

“Consequently, officer recommendation is to grant retrospective planning permission for the single storey rear extension. Recommendation 9.1 That RETROSPECTIVE PLANNING PERMISSION BE GRANTED subject to the following conditions: C1 WITHIN FOUR MONTHS from the date of this permission, the bi-folding doors to the rear elevation shall be installed and the application of the external pebble-dash render applied to all elevations of the extension to accord with the…”

“C2 Those parts of the development hereby permitted which have yet to be built, shall be carried out in accordance with the following approved plans: TRDC001 (Location Plan), PR01 RV02, PR02 RV03, PR03 RV03 & EX04 RV01 Reason: For the avoidance of doubt, in the proper interests of planning and in accordance with Policies CP1, CP9, CP10 and CP12 of the Core Strategy (adopted October 2011), Policies DM1, DM6, DM13 and Appendices 2 and 5 of the Development Management Policies…”

Officer report