Building a New Home in London: Planning, Stages, and What to Expect

The first and often most difficult challenge in a London self-build is finding a suitable plot. London's density means that genuinely available development plots are rare, and competition for them is fierce.

**Types of London self-build plots:**

• •**Garden plots:** Subdividing a large garden to create a new plot. This is the most common source of self-build opportunity in London. The planning position varies significantly — some boroughs actively resist garden subdivision ('garden grabbing'), while others permit well-designed infill development in appropriate contexts.

• •**Replacement dwellings:** Demolishing an existing structure (a garage, a bungalow, or a small house) and replacing it with a larger or better-quality new dwelling. The replacement dwelling typically must be no larger than a certain multiple of the existing structure under local planning policy, though permitted development rights (Class G and H of the GPDO) allow some replacement dwellings in certain circumstances.

• •**Gap sites and brownfield land:** Underdeveloped plots between existing buildings, former commercial sites, and other brownfield opportunities. These require careful feasibility assessment — ground conditions, access, services, and planning history all matter.

• •**Airspace developments:** Building above an existing structure (a garage, a single-storey building, or a lower-density structure) to create new residential accommodation above. Airspace development is technically complex and requires careful structural assessment.

**The planning position for new residential development in London:**

A new dwelling in London requires full planning permission — permitted development does not extend to new dwellings (with very limited exceptions). Key planning considerations include:

• •**Local plan policies on housing and density:** Each London borough has its own policies on where new housing is permitted, what density is acceptable, and what design standards apply.

• •**London Plan standards:** The Mayor of London's London Plan sets minimum space standards (the Nationally Described Space Standard), minimum daylight and sunlight standards, and amenity space requirements that all new dwellings must meet.

• •**Design standards:** New dwellings in London are assessed against the London Plan's design policies and the borough's local design policies — typically requiring good quality design that responds to local context.

• •**Conservation areas and listed building context:** Many London streets are in conservation areas — significant design constraints apply to new buildings in these areas.

**Pre-application advice:** For a new dwelling, pre-application engagement with the borough's planning team is strongly recommended before investing in full planning drawings. Pre-application advice is a paid service (typically £200–£800 depending on the borough and scheme size) but provides useful early feedback on whether a new dwelling is likely to be supported in principle.

A London self-build project typically proceeds through the following stages:

• **Stage 1: Site purchase and feasibility**
• •Purchase or secure option on the plot
• •Commissioning a structural survey (if there is an existing structure), a topographical survey, and a ground investigation
• •Feasibility design: a sketch scheme to test what is achievable on the plot within likely planning parameters
• •Pre-application planning advice
• •Utility connections feasibility: water, gas, electricity, drainage connections to the site

• **Stage 2: Design and planning**
• •Appoint architect and specialist consultants (structural engineer, ecology, daylight/sunlight, heritage if relevant)
• •Develop design to planning stage
• •Submit planning application (typically 8–13 weeks to decision; may involve pre-application consultation)
• •Once planning is granted: develop technical design to construction stage (RIBA Stage 4)
• •Building Regulations application (via approved inspector or local authority building control)

• **Stage 3: Pre-construction**
• •Tender and appoint principal contractor (or design-and-build contractor)
• •Finalise specification and material selections
• •Utility connections arranged
• •Party wall agreements where required
• •CDM notifications (if the project is notifiable — which most new builds in London will be)

**Stage 4: Construction** A new build in London typically takes 14–24 months on site from groundworks start to practical completion, depending on size and complexity:

• •**Months 1–3:** Groundworks, foundations (piling in many London sites due to made-up ground or proximity to underground infrastructure), slab
• •**Months 3–8:** Superstructure (walls, floors, roof frame)
• •**Months 6–10:** Weatherproofing (roof, windows, external doors)
• •**Months 8–14:** First-fix M&E (electrical, plumbing, heating, MVHR)
• •**Months 10–16:** Internal finishes (insulation, plastering, screed)
• •**Months 14–20:** Second-fix (joinery, electrical, plumbing, kitchen, bathrooms)
• •**Months 18–24:** Decoration, external works, snagging

• **Stage 5: Completion and occupation**
• •Building Control completion certificate
• •Structural warranty (typically 10-year warranty with NHBC Buildmark or similar)
• •Occupation and CML (Council of Mortgage Lenders) sign-off if mortgaged
• •Registration of new dwelling with Land Registry

A London self-build is expensive — London construction costs are among the highest in the country, and land costs are very high.

**Typical construction cost ranges:**

• •**Standard specification new build in London:** £2,500–£3,500/m² (gross internal area)
• •**Good specification:** £3,500–£4,500/m²
• •**High specification / architecturally complex:** £4,500–£7,000+/m²

• For a 150m² (gross internal area) four-bedroom house in London at a good specification:
• •Construction cost: approximately £525,000–£675,000
• •Professional fees (architect, structural engineer, specialist consultants): approximately £60,000–£90,000 (10–15% of construction cost)
• •Planning and Building Control fees: approximately £5,000–£15,000
• •VAT: New builds are zero-rated for VAT on construction — a significant saving compared with renovation work (where the 20% standard VAT rate applies to the contractor's labour). Note: this applies to the construction contract, not to professional fees or materials purchased directly by the client.

• **Additional costs often overlooked:**
• •Ground investigation and topographic survey: £3,000–£8,000
• •Utility connection costs: £5,000–£30,000+ depending on location and services available
• •Structural warranty: £1,500–£5,000
• •Stamp Duty Land Tax on the land purchase (if purchased separately from an existing house)
• •Demolition costs if an existing structure is to be removed: £10,000–£40,000

**Financing a London self-build:** Self-build mortgages are available for new builds in London — they release funds in stages as the build progresses (rather than as a single sum on completion). The government's Self-Build Register and Help to Build scheme provide some support, though availability and eligibility criteria vary. A specialist self-build mortgage broker is advisable for this type of project.