Appeal 3374248

The appeal is dismissed.

The council’s description for the proposal differs to that set out in the application form. It describes the proposal as a “hip-to-gable roof extension incorporating increase in ridge height, dormer windows, single storey side/rear extension, first floor rear extension, rooflight and alterations to fenestration following removal of existing chimney.” I consider that the council’s description is more comprehensive although where it states first floor rear extension, it would have been clearer if it had stated first floor rear balcony.

Drawing number 8TR/1/04 shows the flat roof of the existing rear dormer sitting behind the ridge line of the host dwelling. In fact, the eaves of the flat roof dormer sit above the front roof slope. As this minor error does not affect the proposal it has not affected my ability to determine this appeal.

The first main issue is the effect of the proposal on the character and appearance of the host dwelling and the street scene. The second main issue is the effect of the proposal on the living conditions of the occupiers of 7 and 9 The Ridgeway (No.7 & No.9) with particular regard to visual impact and privacy. The third issue is whether the proposal would be flood resilient.

The Ridgeway is characterised by a row of older modest sized similarly designed bungalows with fully hipped roofs. They front onto an enclosed narrow lane and back onto wooded parkland and a marina on the edge of the [name]. At the end of this row of dwellings is a larger “L” shaped bungalow that occupies a larger plot and which is separated from the rest of the row by mature planting along the boundary with The Ridgeway. The dwellings occupy an elevated position, with the land falling away to the rear. This provides views over the marina, the [name], and a modern three storey residential development with hipped roofs.

On the opposite side of The Ridgeway is a flat roofed apartment development which is physically separated from The Ridgeway by their communal gardens, tall fencing, a tall wall, and mature planting. Its character and appearance is completely different to that of the development within The Ridgeway.

Some of the dwellings within the row have modest sized rooflights, comparatively modest sized dormer windows on their front elevations and a variety of single storey additions. Also, a couple of the ridge heights appear to have been raised slightly. Notwithstanding this the dwellings retain their hipped roofs and the changes have been readily assimilated into the street scene. In particular, the changes have not had a material impact on the roofscape of the row of dwellings. The bungalow at the end of the cul-de-sac is materially larger and has a variety of dormer additions. Whilst its appearance is different to the other bungalows, it similarly has a hipped roof.

The appeal dwelling has a rear dormer extension which is prominent due to its width, projection above the ridge line of the host dwelling and dominance of the rear roof slope. Despite this, most of the roofs side hips have been retained and the dormer is set in from the side elevations of the host dwelling. As a result although the existing dormer appears top heavy the proportions of the original dwelling remain.

Amongst other things policy CS17 of the [name] (CS), together with policy DM2 of the Elmbridge Development Management Plan 2015 (DMP), require new development to be of high quality. It should maximise the efficient use of land while taking account of the positive features of the location. Development should be of high quality design and account should be taken of the appearance, scale, height, massing, layout and character of the host building and the prevailing pattern of development. Paragraphs 131 and 135 of the National Planning Policy Framework 2024 (the Framework), state that good design is a key aspect of sustainable development and that proposals should be sympathetic to local character, adding to the overall quality of the area.

Together sections 6.5 and 6.6 of the [name] 2025 (EDC), advise that roofs help frame streets and spaces. They should positively contribute towards the regular rhythm of the street. New dormers should reflect and respond positively to the proportions and positions of existing façade and its openings. Roof extensions and dormers should help maintain the style and appearance of the host building and should avoid dominating the roofscape from a wider view. New roof extensions should reflect and respond to the existing proportions, roof pitch, façade and its openings.

As demonstrated with other roof extensions, in principle the raising of the existing ridge line and introduction of a modest sized front dormer extension would not necessarily have a materially adverse impact on the character and appearance of the host dwelling and the street scene. However, the proposed hip to dormer extension would fundamentally change the character and appearance of the dwelling and interrupt the rhythm of the roofscape. The increased height of the roof would exacerbate its impact.

Due to its height, depth, and width the proposed rear dormer would appear as a full width first floor flat roofed extension. It would appear stark, angular, and top heavy and would unacceptably dominate the rear elevation of the host dwelling. Due to its depth and angular appearance, the proposed balcony and associated railings would exacerbate the harm caused by the rear dormer extension. Whilst these aspects of the proposal would be located to the rear of the dwelling, they would be clearly visible from the rear garden environment and beyond and the cheeks of the dormer and balcony railings would be clearly visible from the street scene where they would appear as a full height flat roofed extension.

The proposed flat roofed wrap around side and rear extension would be modest in form and would sit comfortably within the plot. However, whilst its flat roof appears to align with the eaves of the host dwelling, its small parapet walls to the front and rear would project above the existing eaves line. It would also overlap the front elevation of the host dwelling and the front entrance door would be out of alignment with the top of the windows on the front elevation. As a result, the single storey extension would appear awkward and would fail to respect and blend in appropriately with the host dwelling or the street scene.

I acknowledge that certain aspects of the proposal could be undertaken within the existing permitted development tolerances. However, many of the features that contribute to the harm that would be caused by the proposal fall outside current permitted development tolerances. Also, as required by planning policy where planning permission is required a proposal should be determined in accordance with the development plan and having regard to all other material factors. The appeal has been determined on this basis.

As pointed out by the appellant the bungalow at [address] was built at the same time as the row of bungalows fronting The Ridgeway. However, this dwelling fronts onto [address] where the character of the built environment is more urban and diverse. As such it is not directly comparable to the existing character and appearance of The Ridgeway.

For the reasons set out above I find that the harm that would be caused by the proposal would materially outweigh the benefits that would result from the restoration and refurbishment of the dwelling and the enhanced living conditions for the appellant. Further, this harm is not something that could be satisfactorily dealt with by condition.

I conclude on the first main issue that the proposal would unacceptably harm the character and appearance of the host dwelling and the street scene. Accordingly, it would conflict with DMP Policy DM2, CS Policy CS17, paragraphs 131 & 135 of the Framework and sections 6.5 & 6.6 of the EDC.

I acknowledge that the adjacent living room at No.7 benefits from a large west facing conservatory window and that the secondary side windows may have their blinds pulled for lengthy periods. Nonetheless, they are a notable source of natural daylight and likely add to the sense of space within the living room concerned. Due to their combined close proximity, height and depth the proposed roof/dormer extension and single storey side extension would completely and unacceptably dominate and block the current outlook from the adjacent side windows at No.7.

The proposal would also reduce daylight within the living room and have an enclosing impact on the side passage and entrance to No.7. Whilst in itself this would not amount to a reason for refusal it would exacerbate the proposal’s overbearing impact when viewed from the living room at No.7.

[name] note that there are other side extensions that obstruct the outlook from adjacent side windows within The Ridgeway, they do not involve both deep single storey extensions and two storey gable walls and large first floor dormer cheeks. I also acknowledge that a side and gable extension could potentially be constructed under current permitted development tolerances. However, for the reasons stated in paragraph 13 of this decision I give minimal weigh to this.

DMP Policy DM2 states that development should protect the living conditions of the occupiers of adjoining properties, offering appropriate outlook and adequate daylight, sunlight and privacy. Paragraph 6.5 of the SPD advises that an extension should not result in any significant loss of privacy to adjoining houses and gardens. To prevent overlooking windows should be either high level or obscure glazed. The use of flat roofs as balconies will not usually be acceptable unless well screened or within substantial plots.

With regard to privacy the gardens to the appeal and adjacent properties fall away very steeply to the rear and this results in direct overlooking of the gardens from the three dwellings. The proposed ground floor windows in the side elevation of the proposed ground floor extension would be obscure glazed and the side window in the proposed gable extension could similarly be obscure glazed. Obscure glazed screens could be fitted to the sides of the proposed balcony. This could be secured through the imposition of conditions. Subject to the imposition of such conditions the proposal would not result in a material loss of actual or perceived privacy for the occupiers of No.7 or No.9.

Finally, concern has been expressed that the proposal could affect the stability of the dwelling at No.7. This is a private matter that falls outside the scope of this appeal.

I conclude on the second main issue that the proposal would unacceptably harm the living conditions of the occupiers of No.7 due to its overbearing visual impact. It would therefor conflict with DMP Policy DM2.

The appeal property and part of The Ridgeway are shown as lying within [name] 2 on the submitted [name] map. Section 16 of the Framework states that when determining any planning application, local planning authorities should ensure that flood risk is not increased elsewhere. Where appropriate, applications should be supported by a site-specific flood-risk assessment, although sequential and exception tests are not required for most householder applications. Development should only be allowed in areas at risk of flooding where, amongst other things, the development is appropriately flood resistant and resilient; it incorporates sustainable drainage systems unless there is clear evidence that this would be inappropriate; any residual risk could be safely managed; and safe access and escape routes are included where appropriate, as part of an agreed emergency plan.

The above requirements need to be adequately addressed before planning permission is granted.

As advised in paragraph 020 [name]: 7-[phone] of the National Planning Policy Guidance (NPG): the objectives of a site-specific flood risk assessment are to establish whether a proposed development is likely to be affected by current or future flooding from any source; whether it will increase flood risk elsewhere; and whether the measures proposed to deal with these effects and risks are appropriate. The NPG goes on to advise that Flood risk assessments need to include the information set out in the flood risk assessment checklist and should be appropriate to the scale, nature, and location of the proposed development.

The Environment Agency Standing Advice for [name] (EASA), which was updated in April 2025, requires for all vulnerable developments that its advice should be followed in respect of: • Floor levels • Extra flood resistance and resilience measures • Access and escape • Surface water management

Policy CS26 of the [name] and the Elmbridge Flood Risk Supplementary Planning Document 2016 (SPD), similarly seek to ensure that development is safe and the risk from flooding is minimised. The SPD advises that for modest home extensions in medium to high risk flood areas a site specific flood risk assessment is required to demonstrate that the development is not at risk of flooding and there is no increase in flood risk elsewhere as a result of the proposal.

The appellant has submitted an assortment of information on flood risk although it does not fully address all the questions raised in the Council’s Flood Risk Assessment Small Scale Development Template or the requirements set out in the Framework, the NPG, or the EASA. In particular, precise details of the extra flood resilience and resistance measures incorporated into the design of the development, and a copy of the appellants flood plan have not been provided. Similarly, whilst the side/rear extension would reduce the amount of permeable surfaces on the site, details to show that the existing soakaway could cope with the additional water have not been submitted. Although reference has been made to a flood risk assessment relating to a nearby property in The Ridgeway, a full copy of the document has not been provided. As such I give limited weight to it.

In the absence of the above information it has not been demonstrated that the proposal would satisfy the requirements set out above.

For this reason, I conclude on the third issue that on the basis of the information submitted, it has not been demonstrated that the proposal would be safe and would not increase the risk of flooding elsewhere. Therefore, the proposal conflicts with CS Policy CS26 and the [name].

Having regard to my conclusions on the main issues and all other matters raised the appeal is dismissed.