Direct guidance for homeowners planning substantial residential work in London and Hertfordshire.
There is no single reliable extension price. A standard extension with limited internal change differs materially from a high-spec extension, an extension combined with renovation, structural remodelling or a whole-house refurbishment. Any figures are indicative and depend on scope, design, structure, access, specification, existing condition, site constraints, professional fees and VAT.
Programme depends on design information, planning conditions, structural complexity, procurement, access and finish. The supplied AT Bespoke Build portfolio records substantial extension and renovation projects lasting about seven to fourteen months; this is evidence of those projects, not a universal duration.
Look for genuine projects of comparable complexity, clear responsibility for programme and trade coordination, transparent scope and change control, appropriate insurance evidence, references you can verify, and a contract that matches the design information. Meet the proposed project lead and establish how decisions, costs and quality checks are recorded.
Planning permission is formal local-authority approval for work outside automatic development rights. Permitted development allows certain changes without a full application, but limits and exclusions still apply, so the design and property constraints should be checked before work starts.
A standard extension may focus mainly on creating the new shell and connecting it to the house. An extension plus renovation can also involve major structural openings, service replacement, internal remodelling, kitchens, bathrooms and finishes across the existing property, requiring a wider budget and programme.
The four primary locations are Harpenden, St Albans, Barnet and Muswell Hill. Existing secondary service areas include Colindale, Hendon, Mill Hill, Edgware, Finchley, Golders Green, Hampstead, Wheathampstead, Ealing and Queens Park. Other projects can be assessed on scope, programme and location.
Share the project location, intended work, approximate budget, planning status, desired start date and any architect or engineer information already available. This helps AT Bespoke Build assess suitability before arranging a project consultation.
The main-contractor role coordinates scope, programme, trades, structural information, procurement, quality checks, communication and handover. The exact approach depends on the project documents and agreed contract.
Share your project location, scope, planning status and intended budget for an initial suitability assessment.