A roof alteration can make an existing extension feel much more closely related to the house it serves. At 40 Alicia Gardens in Kenton, Harrow, our proposal replaces the mixed flat and pitched roof over a first-floor side extension with a more consistent pitched form. The aim is to improve the roof’s appearance and renew a part of the building identified as needing replacement.
Harrow Council granted householder planning permission on 3 August 2026 under application PL/1356/26. This is a targeted improvement to the existing house, with the design concentrating on roof shape, materials and the relationship with the neighbouring property.
Bringing the side extension into the roofscape
The existing drawings show a side addition whose roof changes between pitched and flat sections. That junction gives the extension a different profile from the main house. The proposed roof removes the flat section and realigns the lower ridge so that it meets the rear roof slope.
Keeping that secondary ridge below and behind the main ridge is an important part of the composition. It allows the original roof to remain the dominant form, while the extension reads as a more coherent part of the property. This kind of careful adjustment is central to our architectural design services: a relatively small change can improve how several existing parts of a home fit together.
Matching materials and maintaining the gap next door
The proposed roof uses tiles similar to those already on the house. Matching external materials is also a condition of the permission, giving the renewed roof a clear relationship with the existing building.
At the side boundary, the drawings continue the parapet while maintaining the existing gap to the neighbouring property. The roof is therefore considered in the context of both houses, including the way their upper floors and roof edges meet in the street view. The planning statement also identifies a comparable roof arrangement at the neighbouring property as part of the local context.
For homeowners considering similar alterations, our architectural services in Harrow bring together the design of the house and the information needed to explain the proposal to the council.
Working through the construction details
The planning drawings identify opportunities to remove an internal bulkhead and review the opening beneath the altered roof, subject to structural input. Those details matter to how the space is used, but they need to be resolved alongside the roof structure and insulation.
The subsequent technical work has included coordination of ceiling levels, supporting structure, insulation and ventilation. Our building regulations drawings and technical design service addresses these construction questions after the planning design has been established. The aim is to give the builder a coordinated roof replacement package, with the proposed insulation changes subject to Building Control’s thermal requirements.
Considering a roof alteration?
If an existing extension has an awkward roof junction or needs renewal, arrange a call about your property. We can review the existing form, discuss the changes you want to make and advise on the appropriate design and application steps.
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