How Long Does a New Build House Take in London? 2026 Guide

One of the most common questions from clients considering a new build house in London is how long the process takes from start to finish. The honest answer is that a new build project is a significant undertaking with multiple stages — and understanding the full timeline before committing to a project helps you plan realistically. LCCL Construction delivers new build houses across London, Hertfordshire and Bedfordshire and manages every stage of the process as part of our complete design and build service.

LCCL Construction — specialist new build design and build company across London, Hertfordshire and Bedfordshire

How Long Does a New Build House Take London From Start to Finish?

How long does a new build take London. A typical new build house in London takes 18 to 30 months from initial design to final completion. This covers the full project timeline including architectural design, planning permission, building regulations, site preparation, construction and finishing. Simpler projects on uncomplicated sites in outer London or Hertfordshire can complete in 18 to 22 months. Complex projects in conservation areas, on contaminated sites, or requiring extensive pre-application consultation can take 28 to 36 months or longer.

New Build Timeline Stage by Stage

Stage 1 — Initial feasibility and design brief: 4 to 6 weeks. LCCL Construction visits the site, assesses planning feasibility, prepares an initial cost estimate and agrees the design brief with you.

Stage 2 — Architectural design: 6 to 10 weeks. Our architects prepare the measured survey, existing drawings, proposed floor plans, elevations and sections. We discuss and refine the design with you before finalising the planning drawings.

Stage 3 — Pre-application consultation (where required): 4 to 8 weeks. For complex sites we recommend pre-application consultation with the local planning authority before formal submission. This identifies potential issues and improves the chances of first-time approval.

Stage 4 — Planning permission: 8 to 13 weeks from submission. All new builds require full planning permission. The statutory determination period is 8 weeks for standard applications and 13 weeks for major applications. Conservation areas and sensitive sites can take longer.

Stage 5 — Building regulations and structural design: 6 to 10 weeks. Running alongside or immediately after planning permission, the building regulations package includes structural calculations, energy calculations, drainage design and detailed construction drawings.

Stage 6 — Site preparation and groundworks: 4 to 8 weeks. Demolition of existing structures if required, site clearance, foundation excavation, drainage installation and concrete foundations or piled foundations depending on ground conditions.

Stage 7 — Superstructure construction: 16 to 28 weeks. Building the walls, floors and roof structure — the main construction phase. Includes external masonry or timber frame, floor structures, roof structure, roof covering and external windows and doors.

Stage 8 — First fix and second fix: 8 to 14 weeks. Internal partitions, first fix electrics, plumbing and heating, insulation, plasterboard, plastering, second fix electrics, plumbing and heating, kitchen, bathrooms and decoration.

Stage 9 — Completion and handover: 2 to 4 weeks. Snagging, final building control inspection, sign-off, landscaping and handover.

What Causes New Build Projects to Take Longer?

The most common causes of delays in new build projects are: planning permission taking longer than expected, particularly in conservation areas or for complex applications; ground conditions requiring more extensive foundations than anticipated; utility connections taking longer than planned; design changes requested during construction; material supply delays; and adverse weather during the superstructure phase. LCCL Construction's experienced project managers anticipate these risks and build appropriate contingency into every programme.

How Does a New Build Timeline Compare to an Extension?

A house extension typically takes 5 to 12 months from initial consultation to completion — significantly faster than a new build. However a new build creates an entirely new property rather than adding to an existing one, and the zero-rated VAT treatment makes it more cost-effective per square metre than an extension at scale. The right choice depends on your site, budget and objectives.

Frequently Asked Questions About New Build Timelines

How long does it take to build a house in London?

The full process from initial design to completion typically takes 18 to 30 months including planning permission and construction.

How long does planning permission take for a new build?

Planning permission typically takes 8 to 13 weeks from submission. Pre-application consultation adds 4 to 8 weeks but improves the chances of first-time approval.

How long does construction take for a new build house?

The construction phase from groundworks to completion typically takes 12 to 18 months for a standard family house.

To discuss your new build project call LCCL Construction on 020 8037 7332 or get an instant quote online.