
Whole-house refurbishment with rear extension and loft conversion
Hill Crescent
Totteridge, North London N20

Hertsmere · WD23
Extensions, loft and basement conversions, renovations and new homes in Bushey, designed and built by Milkov & Son from our base in Hendon.
Bushey and Bushey Heath sit on the ridge between Stanmore and Watford: Victorian villas along the High Street and Bushey Heath, Edwardian and inter-war houses on the roads between, and large detached houses towards the common and Merry Hill. Milkov & Son works here on extensions, lofts, renovations and the occasional new house, from Hendon via the A41.
Bushey village has a Victorian and Edwardian core (the artist Hubert von Herkomer's influence is still visible) in the Bushey High Street and Melbourne Road conservation areas, with substantial villas and terraces. Bushey Heath has larger detached houses, some Victorian, many inter-war and post-war, in and around its own conservation area, with the green belt and Bushey Heath common beyond. Oxhey and the Watford side are 1930s semis and detached houses. Hertsmere has Article 4 directions on several Bushey properties and groups.
Bushey is in Hertsmere Borough Council's area. Outside the conservation areas, houses retain permitted development rights and rear extensions and rear dormers are routine. In the Bushey High Street, Melbourne Road and Bushey Heath conservation areas — and where Article 4 directions apply, for example on Warren Road — external alterations need permission and are judged against the conservation area appraisals and Hertsmere's design guidance. Green-belt limits apply on the common edges. Householder applications are decided within eight weeks of validation.
Rear and wraparound kitchen extensions; loft conversions on the 1930s houses; whole-house renovations of Victorian villas with restored features; and larger extensions and replacement dwellings in Bushey Heath.
The High Street and the village conservation streets have limited parking and need skip and scaffold permits; Bushey Heath and Merry Hill plots are generous. The ridge geology mixes clay with gravel; we check before designing foundations and basements. Bushey station (Overground and West Coast main line) and the A41 make site visits straightforward.
Planning authority: Hertsmere Borough Council. Conservation-area boundaries and Article 4 directions change; we confirm the position for your address before advising.
Yes — Bushey, Bushey Heath, Merry Hill, Oxhey and the Watford border, WD23 and WD19.
Hertsmere's conservation areas in Bushey are Bushey High Street, Melbourne Road and Bushey Heath, with Article 4 directions on some properties. We check the designation from your address before advising on the planning route.
As a 2026 guide, £70,000–£130,000 plus VAT and fees for a 20–30 m² single-storey rear extension; specification, structure and ground conditions move the figure.

Rear, side return, wraparound, double storey and kitchen extensions — designed, approved and built by one team.

Dormer, hip-to-gable, L-shaped and mansard conversions that add a bedroom and bathroom without touching the garden.

Whole-house refurbishments and reconfigurations of 1930s, Edwardian and Victorian homes, managed as one project.

Feasibility, design, approvals and construction under one contract, with one person accountable for the result.
Based in Hendon, we work across North London and the Hertfordshire border. Each area page covers the local housing stock, planning context and the kind of work we do there.
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Send a few details about the property, what you want to achieve and your approximate budget. Stoyan reads every enquiry and replies within one working day.
What happens next: a short call, a site visit if it is a good fit, then a written proposal. No charge, no obligation.