Prime Residential Builders
in Harrow

A London prime contractor, minutes from Harrow

Crown Building has been delivering prime residential construction since 2013, and Harrow sits comfortably within the daily operating radius of our Watford headquarters. While much of our work is in the prime central London postcodes, Mayfair, Chelsea, Knightsbridge, Belgravia, our roots, our team and our registered office are minutes away. For homeowners in Harrow, that means a contractor working to a genuine prime residential standard, with senior management close enough to be on site whenever the project needs them.

We do not operate at volume. We compete on execution. The discipline that the best London projects demand, meticulous programming, a trusted specialist supply chain, senior management present on site throughout. Is exactly what we bring to a home in Harrow. The standard does not change with the postcode.

What we build in Harrow

Our residential work spans the full scope of high end building. We deliver architecturally distinctive new build homes, private residence refurbishments and structural reconfigurations, single and multistorey extensions, basement excavations, listed and period property works, and the bespoke joinery and interiors that define a finished home. Each project is delivered as design and build or contractor only, with Crown appointed as your prime residential main contractor, and transparent, itemised pricing from the outset. Commercial occupiers are served by the same teams through our commercial fit out division, and clinical and wellness premises through our healthcare and specialist environments team.

Harrow on the Hill remains one of north west London's most distinctive conservation areas, Georgian and Victorian houses on steep, narrow streets where access, logistics and neighbourly relations demand careful preconstruction planning. Down the hill, the borough's stock runs from generous 1930s Metroland detached homes to Edwardian terraces ripe for reconfiguration. Loft conversions, rear and side extensions and private residence refurbishments dominate the brief here, and the difference between an average result and an exceptional one is almost entirely in the execution.

Areas we serve

We work throughout the borough, Harrow on the Hill, Harrow Weald, Hatch End, North Harrow, Pinner borders, Kenton and Northwick Park. As well as neighbouring Stanmore and Bushey, both minutes from our office. You can see our full coverage, London within the M25 and a fifteen mile radius of our Watford headquarters, on our areas we cover page.

A new Local Plan, adopted March 2026, with a new basement policy

Harrow adopted its Local Plan 2021 to 2041 on 24 March 2026, superseding the 2012 Core Strategy and the 2013 Development Management policies. Anyone working from the older documents is working from superseded policy, and on basements the position has changed.

Basements are now governed by Policy GR4A. A basement is limited to a maximum of fifty per cent of the site's amenity space and must not extend into the rear garden by more than fifty per cent of the depth of the host dwelling measured from the principal rear elevation. A construction method statement is mandatory. Two features of the policy are worth knowing before designing: basement space must be ancillary to the main dwelling, with self contained units refused, and habitable space is refused in Flood Zones 3a and 3b. GR4A sets no storey cap, no soil depth figure and no boundary set back, so those aspects fall to be judged on the general design and amenity tests rather than against a number.

Thirty conservation areas, eight of them on the Hill

Harrow has thirty conservation areas, an unusually high number for an outer borough, and Harrow on the Hill alone accounts for eight of them including Harrow School, Harrow on the Hill Village and the Mount Park Estate. Article 4 directions are conservation area specific rather than borough wide, and are confirmed at Harrow Park, Harrow on the Hill Village, South Hill Avenue and the Mount Park Estate among others.

The Harrow School estate is a case of its own. It has its own supplementary planning document and masterplan, sits on Metropolitan Open Land within multiple conservation areas, and is subject to protected view corridors towards St Mary's spire. Building anywhere in its vicinity engages that framework, and the view corridors in particular constrain height and roof form in ways that are not obvious from the street.

Green Belt and Metropolitan Open Land across a fifth of the borough

Around twenty one and a half per cent of Harrow is Green Belt, with a further three hundred and thirteen hectares designated Metropolitan Open Land. On those addresses the national tests apply: extensions must not be disproportionate over and above the size of the original building, and replacement dwellings must not be materially larger than the ones they replace.

The borough has over three hundred statutory listed buildings and a local list running to more than seven hundred entries. Local listing is a material consideration rather than a statutory control, but on the Hill in particular it shapes what officers will accept, and it is worth establishing the status of a property before a scheme is drawn rather than after.

Speak to us about your Harrow project

If you are planning a build, refurbishment or extension in Harrow, call us on 020 3675 3999 or book a free consultation here. Our registered office is Unit 324-B, The Wenta Business Centre, Colne Way, Watford, WD24 7ND.

Frequently asked questions

Where is Crown Building based?

Crown Building's registered office is at Unit 324-B, The Wenta Business Centre, Colne Way, Watford, WD24 7ND. We work throughout London within the M25 and across Hertfordshire and the Home Counties.

Which areas around Harrow do you cover?

We cover all of Harrow, including Harrow on the Hill, Harrow Weald, Hatch End, North Harrow, Kenton and Northwick Park, plus neighbouring Stanmore, Pinner and Bushey.

Do you handle extensions and loft conversions in Harrow?

Yes. Single and multistorey extensions, loft conversions and private residence remodelling are core work for us in Harrow, delivered with the same senior led site management as our prime central London projects.