Appeal 3326834

The appeal is dismissed.

The main issue is the effect of the proposed extension on the character and appearance of the host dwelling and the surrounding area.

The appeal property is a detached dwelling located in a residential road of properties of varied design and appearance.

Policy DM23 of the Chelmsford Local Plan (2020), concerning high quality and inclusive design, states that planning permission will be granted for extensions and alterations to existing buildings that are of a high quality design; and are compatible with the character and appearance of the area, and also where relevant the host building, in terms of the siting, scale, form, massing, materials and detailing.

The Making Places Supplementary Planning Document (SPD) provides further details concerning dormer windows. It says that dormers should not be over-dominant due to their individual or cumulative size or shape; and dormer windows should not disrupt the host building's roof form, and on the front or other prominent roof slopes, dormer windows should be of a modest size and traditional design providing light rather than headroom or extra floorspace1. 1 Paragraph 8.8.

No 39 has an asymmetrical front gable with a large forward-facing roof slope adjoining this on which the existing dormer is positioned. The current feature is proportionate to the main roof form and is situated in the middle of the roof slope. It is inset from either side of the slope and is below the main ridge with a good degree of separation from the eaves. As such, it reflects the policy and related guidance referred to above.

The proposed extended dormer would be of the same height as the existing one, but it would be substantially larger as a result of its forward projection. This would harmfully alter the relationship of the dormer to the host dwelling due to the disproportionate size of the dormer, which would be particularly evident from the bottom of the front elevation being at eaves height. This would result in an awkward, cramped relationship with the ground floor window below it. Moreover, this incongruous appearance would be heightened by the overhang, which together with the white painted render would draw the eye to the dormer as a dominant feature on the front roof slope that would upset the proportions and appearance of the host dwelling.

While the street scene comprises properties of varied character and appearance, the appeal property and its neighbour, No 41, are of similar overall design. The neighbouring dwelling has a similar-sized dormer in the same position as that at No 39, although it has a flat rather than pitched roof. Nonetheless, in addition to the above findings, the extended window would also be particularly apparent within the street scene due to the contrast between the scale and appearance of the dormers on similar neighbouring dwellings.

I acknowledge that the purpose of the extended dormer is to create more living space due to the size limitations of the room it serves. However, given the above findings, the proposal conflicts with guidance in the SPD that dormers should not disrupt the host building's roof form and on the front or other prominent roof slopes, dormer windows should be of a modest size providing light rather than headroom or extra floorspace.

The appellants draw attention to examples of jettied gables and contend that these are a common built form within the wider area. [name] accept this, the examples provided are full gables on much older buildings, as opposed to the appeal proposal, which involves a dormer window on a more modern property. As such, the examples provided are not directly comparable and do not overcome the above findings of harm in the particular circumstances of this case.

I have had regard to the representation made by [name] & Bicknacre Parish Council in support of the proposal. This does not, however, raise any substantive matters that overcome the above findings.

Accordingly, for these reasons, I conclude that the proposed extension would have an unacceptably harmful effect on the character and appearance of the host dwelling and the surrounding area. Consequently, it is contrary to Policy DM23 of the Chelmsford Local Plan, described above. It is also contrary to the National Planning Policy Framework, which advocates good design. 2

For the reasons given it is concluded that the appeal should be dismissed.