Planning permission drawings, rear extensions, and loft conversions for Blackfen's 1930s semis and bungalows. MCIAT chartered, Bexley planning expertise built in.
Blackfen sits in the DA15 postcode within the London Borough of Bexley, bordering Sidcup to the south and Welling to the north. The neighbourhood's 1930s housing stock and wide plot sizes make it one of south-east London's most extension-friendly areas.
1930s semi-detached stock: The majority of Blackfen's housing is inter-war semi-detached with generous rear gardens and hipped roofs. These properties are ideal for hip-to-gable loft conversions, rear extensions, and side infills. We design schemes that maximise space while respecting the original character.
Permitted development: Outside conservation areas, most Blackfen properties retain full permitted development rights. Rear extensions up to 6m (detached) or 4m (semi) under prior approval, hip-to-gable loft conversions under Class B, and two-storey side extensions in many cases. We confirm your PD eligibility and prepare the required drawings.
Bexley planning standards: Bexley Council has clear design guidance emphasising subordinate, matching materials and respect for the existing streetscape. Applications that demonstrate compliance with council guidance typically receive straightforward approval.
Bungalow conversions: Blackfen has a notable stock of 1930s bungalows. Converting the loft to create a first floor — or adding a full first-floor extension — is a popular way to increase family space without moving. Structural calculations and careful massing are essential.
Single planning or regs submission.
Planning + building regs + structural.
Listed, conservation, complex sites.
Direct answers to the questions Blackfen homeowners ask us every week about planning, extensions, and loft conversions.
Start a free quoteIn most cases, no. Rear extensions up to 6m (detached) or 4m (semi-detached) from the original rear wall can proceed under permitted development with a prior notification. Larger extensions or those in conservation areas require planning permission. We confirm your position and prepare drawings.
Yes — bungalow loft conversions are common in Blackfen. A hip-to-gable conversion with a rear dormer is the typical pattern, and often falls within permitted development. Structural calculations are essential. We prepare the full drawing package.
Bexley emphasises subordinate extensions, matching materials, and respect for the streetscape. Two-storey side extensions must be set back and down from the main roof. We design to Bexley's published guidance.
Bexley targets 8 weeks for householder applications. Lawful Development Certificates and prior approval notifications are typically faster. We manage the full application timeline.
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Every service you need for a Blackfen project, from a single chartered team.
Rear extensions, side returns, wraparounds, and basement feasibility for local housing stock.
Dormers, mansards, and Velux conversions designed for local roof profiles and planning constraints.
Construction-ready drawing packages compliant with all Approved Documents, submitted to local Building Control.
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