Single and two storey side extension, two rear dormers and external alterations

Appeal Decision Site visit made on 4 June 2019 by M Russell BA (Hons) DipTP MRTPI an Inspector appointed by the Secretary of State Decision date: 27 June 2019 Appeal Ref: APP/M5450/D/19/3225011 47 Spencer Road, Harrow, Middlesex HA3 7AN • The appeal is made under section 78 of the Town and Country Planning Act 1990 against a refusal to grant planning permission. • The appeal is made by Mr & Mrs Ahmed against the decision of the Council of the London Borough of Harrow. • The application Ref P/4900/18, dated 5 November 2018, was refused by notice dated 17 January 2019. • The development proposed was originally described as single and two storey side extension, two rear dormers and external alterations. Decision 1. The appeal is allowed and planning permission is granted for single and two storey side extension, two rear dormers and installation of rooflights to front roofslope; external alterations at 47 Spencer Road, Harrow, Middlesex HA3 7AN in accordance with the terms of the application, Ref P/4900/18, dated 5 November 2018, subject to the following conditions: (1) The development hereby permitted shall begin not later than 3 years from the date of this decision. (2) The development hereby permitted shall be carried out in strict accordance with the following approved drawings: 1:1250 47 Spencer Road Site Location Plan; SHT. No.2 Proposed Plans and SHT. No.3 Existing & Proposed Elevations. (3) Before development commences, a scheme to mitigate flood risk shall be submitted to and approved in writing by the local planning authority. The scheme shall include confirmation of which of the flood mitigation measures set out at paragraphs 7.3 – 7.13 of the Flood Risk Assessment (FRA) dated 21 November 2018 are to be incorporated into the development and any additional mitigation measures not previously set out in the FRA. Once agreed in writing, the development shall only be carried out in full accordance with the approved scheme. Procedural Matter 2. The Council slightly amended the original description of the proposal to include a reference to the proposed rooflights to the front roofslope. I have assessed the proposal based on this revised description given this more accurately describes the proposal. Appeal Decision APP/M5450/D/19/3225011 2 3. The proposed drawings include a porch extension. This is not specifically included in either the Council’s or the appellant’s description of development. However, given its modest proportions the porch could fall under the ‘external alterations’ element of the description. The Council’s delegated report makes an assessment of the porch concluding the design is acceptable. I therefore consider no party would be prejudiced if I consider the porch as part of my assessment. 4. The submitted details include confirmation that the proposed development would be part of an intention to convert the building from the existing two flats, one at ground floor and one at first floor, back to a single dwellinghouse. This conversion does not form part of the description of the proposal and I have nothing before me to suggest that this constitutes a form of development in this instance. This matter has not therefore formed part of my assessment. Main Issues 5. The main issues are: • The effect of the proposal on the character and appearance of the area; and • Whether the proposal would result in increased flood risk for occupants of the host dwelling and neighbouring properties. Reasons Character and appearance 6. Spencer Road is characterised by mainly two-storey semi-detached dwellings, many of which have a distinctive front gable feature. No 47 Spencer Road is one such dwelling. The original proportions of the dwelling at No 47 were lost when it was previously extended. The extensions to No 49 have also altered the balance of the front elevations of this pair of semi-detached dwellings within the streetscene. 7. The Harrow Council Supplementary Planning Document – Residential Design Guide (2010) (SPD) requires amongst other things that extensions to dwellinghouses harmonise with the scale and architectural style of the original building and that proposals should not dominate the original building or surrounding streetscape. 8. Whilst I acknowledge the proposed side extension has not been designed so as to appear subservient to the original dwelling, it would have a similar appearance to the two-storey side extension at No 49. It would replicate the roof line to match the main ridge and would have a front elevation aligned with the main front elevation of the dwelling. Whilst increasing the overall scale of the host dwelling, the existing front projecting gable would remain as a prominent feature on the front elevation. Furthermore, the windows on the front elevation of the extension would be of similar proportions and would be well aligned with each other and with the proposed front door. The proposed porch is modest in proportion and would successfully integrate with the appearance of the front elevation. These design features would give the pair of semi-detached dwellings a more balanced appearance without dominating the original building or the streetscene. Appeal Decision APP/M5450/D/19/3225011 3 9. To the rear, the proposed dormer windows would be set in from the sides, eaves and ridge of the rear roof slope of the extended dwelling. There would also be a gap between the dormers. Consequently, the design of the dormers would be similar to that specified in the design criteria under Paragraph 6.72 of the SPD. The dormers would appear relatively modest and would not appear as bulky or dominant additions to the roof slope. Any interjection by one of the dormers into the valley between the main roof and the roof of the existing two storey rear projection would be marginal and not so disruptive to the roof form that it would appear incongruous. 10. The proposed single storey rear extension would extend an existing flat roofed projection and would also have a rear elevation aligning with the existing two storey rear projection. The Council suggests that the depth of the extension would exceed that recommended in the design guidance under Paragraph 6.59 of the SPD. However, when seen in combination with scale of the side extension, the rear extension would not appear out of scale and overall the extensions would have a unified appearance. 11. The Council contends that the proposed door to the front elevation of the two- storey side extension would give the impression that there are two dwellings which would not be in keeping with the general pattern of development. Whilst acknowledging that usually a single dwelling would only have a single door to its front elevation, the proposed door would replace an existing second entrance door. The new door would also be better positioned in terms of its alignment with other fenestration on the front elevation. In this particular instance, given two front entrance doors is an established feature to No 47, I consider any impact on the street pattern is diminished and would not on its own warrant a reason to dismiss the appeal. 12. My attention has also been drawn to other dwellings within the street that have similar two storey side extensions. These examples further demonstrate that the proposal would not be out of character with the design and scale of other dwellings on Spencer Road. 13. To conclude, the proposals are of a scale, form and design which would improve the balance and appearance of the semi-detached dwelling taking into account the local context and would make a positive contribution to the character and appearance of the area. The proposal would therefore comply with Policy 7.4B (Local Character) and 7.6B (Architecture) of the London Plan (2016), Policy CS1.B (Overarching Policy) of the Harrow Core Strategy (2012) (CS) and Policies DM1 (Achieving a High Standard of Development) and DM2 (Delivering good design) of the Harrow Council Development Management Policies (2013) (DMP). Flood risk 14. The location of the site within an area of flood risk is not disputed. National Planning Practice Guidance confirms that an FRA should be appropriate to the scale, nature and location of the development. For an extension to an existing house which would not significantly increase the number of people present in an area of flooding, generally a less detailed assessment is required to be able to reach an informed decision. 15. I note that the two-storey extension and ground floor rear extension would replace existing extensions and hard surfacing on a similar footprint. The Appeal Decision APP/M5450/D/19/3225011 4 number of bedrooms within the building would be increased by one and therefore the scale of the extension could not be described as being likely to result in a significant increase in the number of people present in an area of flooding. 16. The Council has not set out why flood data and flood displacement storage details are a specific necessity in this particular instance. The FRA confirms that in line with Environment Agency advice, floor levels within the development would be set no lower than existing floor levels and flood proofing would be incorporated where appropriate. Various other mitigation measures are also set out at paragraphs 7.4 – 7.13 of the FRA including means to manage surface water run-off. 17. I note the appellants would be willing to accept a condition requiring additional flood mitigation measures to be incorporated above and beyond those recommended in the FRA. Taking into account the particular circumstances of the case, I consider a condition requiring confirmation of which of the mitigation measures suggested in the FRA are to be incorporated into the development and any other mitigation measures would provide suitable assurance that flood risk can be effectively managed whilst also ensuring any such measures are proportionate to a domestic extension. 18. The decision notice suggests the site is located within Environment Agency (EA) Flood Zone 2 and Harrow Strategic Flood Risk Assessment (SFRA) zones 3a and 3b. The Council’s delegated report refers to the West London Strategic Flood Risk Assessment (2018) (SFRA). I have not been provided with a copy of the SFRA’s referred to. However, from the evidence before me and assessing the proposal against the relevant policies of the development plan, it is unlikely these documents would alter my conclusion that an appropriate level of mitigation can be secured by condition in this instance. 19. To conclude, taking into account the site specific circumstances, the proposal would incorporate mitigation measures to ensure flood risk for occupants of the host dwelling and neighbouring properties is not unacceptably increased beyond the existing situation and would therefore be in general accordance with the relevant parts of Policies 5.12B (Flood Risk Management) and 5.13A (Sustainable Drainage) of the London Plan, Policy CS1.U of the CS and Policies DM9 (Managing Flood Risk) and DM10 (On Site Water Management and Surface Water Attenuation) of the DMP which seek amongst other things that the design and layout of proposals minimise the risk of flooding on site and not increase flood risk elsewhere, achieve appropriate finished floor levels, make provision for the control of surface water runoff making use of sustainable drainage measures wherever feasible and comply with the flood risk assessment and management requirements in the National Planning Policy Framework. Conditions 20. In addition to the standard time limit I consider it reasonable to attach a condition to confirm the approved drawings in the interests of certainty. The drawings already confirm that the external surfaces of the development would include slate tiles to match the existing dwelling and that the existing render on the dwelling is to be removed with all new and existing elevations to be finished with a smooth white render. I consider the materials indicated on the submitted drawings would complement the host dwelling and would have an Appeal Decision APP/M5450/D/19/3225011 5 acceptable relationship with the character and appearance of the area. Consequently, a separate condition requiring materials to match the existing dwelling is not necessary. I also attach a pre-commencement condition in respect of the aforementioned confirmation of flood mitigation measures to be incorporated. Conclusion 21. For the above reasons the appeal is allowed. M Russell INSPECTOR