MCIAT chartered drawings · Fixed fees across all 33 London boroughs

Free 2026 London Planning ReportNew Build Drawings in Harrow

Dormer loft bedroom in a London home, a popular Harrow interwar-semi conversion
Harrow · London

New Build Drawings in Harrow

Fixed-fee, MCIAT-chartered new build drawings for Harrow homeowners — London Borough of Harrow validation and local constraints handled from the start.

Free Harrow planning assessment

Tell us your Harrow address and project. A fixed quote and free planning appraisal land within one working day.

No obligation · No spam · Reply within 1 working day

Harrow is Metro-land in built form: rows of interwar semi-detached and detached houses across Rayners Lane, Kenton, Stanmore and Wealdstone that lend themselves to hip-to-gable and dormer loft conversions and rear extensions. On these homes such work frequently qualifies as permitted development within the volume limits, so a full application is not always needed. The London Borough of Harrow pays close attention to preserving the rhythm and consistent 1930s building line of these suburban streets, and expects extensions to respect the established line and roof form of the neighbouring houses.

The picture changes in the borough's heritage cores. Harrow on the Hill carries a protected heritage setting and long views, and Pinner's medieval high street and Pinner Hill, along with Roxeth and Harrow Weald, are conservation areas where permitted development is often restricted and a full, context-led application is required. Harrow also applies Article 4 directions to HMO conversions in designated wards and to front-boundary and hardstanding works in some areas, so the right route depends on your exact address rather than the house type alone.

We prepare Harrow planning drawings that respect the building line and roof form the borough expects, checking permitted development eligibility for semi-detached and detached homes first and confirming it with a Lawful Development Certificate where the work qualifies. In the conservation areas we design to the character of the area — materials, proportions and rooflines — and evidence the heritage considerations so the submission stands up. The fee is fixed and agreed up front, usually around 30% below an architect's charge for the same council-accepted drawings, with free redraws until Harrow approves. Drawing to the council's validation checklist, and turning drawings around in roughly seven days, keeps most applications inside the statutory eight-week determination without a validation query.

Dormer loft bedroom in a London home, a popular Harrow interwar-semi conversion
Isometric illustration of a Harrow home extension design
Proposed floor plan
Harrow

Planning in Harrow: what to know before you apply

Harrow applies Article 4 directions to HMO conversions in designated wards and controls development within Harrow on the Hill and Pinner conservation areas. For the borough's abundant 1930s semis, hip-to-gable lofts and rear extensions frequently qualify as permitted development.

Typical Harrow housing stock

Classic Metro-land interwar semi-detached and detached houses, with the historic hilltop core of Harrow on the Hill and Pinner's medieval high street.

Areas we regularly draw for in Harrow

Harrow · Pinner · Stanmore · Wealdstone · Rayners Lane · Kenton · Hatch End

New Build Drawings for Harrow homes: the package and the process

Every new build drawings we prepare for a Harrow property is drawn to London Borough of Harrow’s validation standards and tuned to the local constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.

Designing a new dwelling on an infill or backland plot in London is a longer and more technically demanding journey than an extension or loft conversion — it involves establishing whether the plot can support a new home at all, securing full planning permission against a borough's density, design and amenity policies, and then producing a building regulations and structural package detailed enough to actually build from. DrawingsDirect delivers all of this as one coordinated service: feasibility, full planning drawings, building regulations drawings and structural calculations, produced in-house rather than passed between separate architects, engineers and drafters who each need briefing and coordinating separately.

London infill and backland sites bring specific challenges that a straightforward extension does not: the impact of a new dwelling on neighbouring daylight and sunlight, privacy and overlooking, the character and density of the surrounding streetscape, and access, parking and refuse arrangements for a new independent home. Getting an early, honest read on these issues — before a full application is drawn and submitted — is often the difference between a scheme that is approved and one that is refused and has to be reworked. We assess feasibility and, where useful, prepare pre-application advice before committing to a full drawing set.

Is my plot suitable for a new build in London?

A feasibility assessment looks at plot size and shape, access, existing boundary conditions, relevant planning policy for the borough, and the likely impact of a new dwelling on neighbouring properties before any design work begins. Infill plots — a gap between existing buildings on a street — and backland plots — a garden or yard site behind existing houses, reached by a shared access — each raise different issues: infill schemes are usually judged on how well they match the scale, spacing and character of the street, while backland schemes are judged heavily on overlooking, garden loss for neighbours, and whether the access arrangement is acceptable. A feasibility study gives an honest view of whether a scheme is likely to succeed before you commit to full drawings.

What does pre-application advice add to a new build project?

Pre-application advice is a formal, paid process most London boroughs offer, where planning officers give written feedback on a proposed scheme before a full application is submitted. For a new build — where the principle of development itself is often the main issue, not just the design details — this feedback can be invaluable: it surfaces concerns around density, massing, daylight and sunlight or heritage context early enough to be addressed in the drawings, rather than discovered for the first time as a refusal reason months into a full application. We prepare and submit pre-application enquiries as part of the new build service where it is likely to strengthen the eventual planning application.

New build project stages
StageWhat it establishesTypical fee guide
FeasibilityWhether the plot can support a new dwelling and the likely constraintsQuoted individually, from within the £2,500 new build fee
Pre-application adviceWritten borough feedback on the scheme before a full applicationQuoted individually alongside the planning fee
Full planning drawingsThe complete drawing set submitted for planning permissionFrom £2,500
Building regs and structuralConstruction-ready drawings and calculations for buildingFrom £2,200–£3,850, quoted once planning is settled
FAQ

New Build Drawings in Harrow — FAQs

How much do new build drawings cost in London?+
New build drawings start from £2,500 for feasibility and a full planning drawing set on a straightforward infill or backland plot, with building regulations and structural drawings quoted separately once the planning design is agreed.
Can any garden or backland plot be built on in London?+
Not necessarily — backland and garden plots are assessed on access, overlooking, loss of garden amenity for neighbours and borough policy, and a feasibility assessment gives an honest early view of whether a scheme is likely to be supported.
Do I need pre-application advice before a full new build application?+
It is not mandatory, but for a new dwelling — where the principle of development is often the main issue — pre-application advice can surface concerns early enough to address them in the design, reducing the risk of refusal.
Do you handle building regulations and structural drawings for a new build, or only planning?+
Both — the full new build service covers planning, building regulations and structural drawings from one in-house team, so the design stays consistent from feasibility through to construction-ready drawings.
How long does a new build project take from feasibility to planning permission?+
This varies with site complexity and whether pre-application advice is sought, but a full planning application is determined within the statutory period the borough applies to the application type, once submitted via the Planning Portal.
Do I need planning permission for a loft conversion in Harrow?+
Harrow's Metro-land semis and detached houses in Rayners Lane, Kenton and Stanmore suit hip-to-gable and dormer lofts, which frequently qualify as permitted development within the volume limits. The exceptions are the conservation areas — Harrow on the Hill and Pinner's historic core — and the Article 4 wards. We check your address and can confirm permitted development with a Lawful Development Certificate.
What does Harrow expect for a rear extension on a 1930s semi?+
The council pays close attention to preserving the rhythm and building line of its interwar suburban streets, so extensions are expected to respect the established line and roof form. Many single-storey rear extensions still fall within permitted development; where a full application is needed, we design to the borough's residential guidance so it validates and approves without repeated revisions.
Can I extend a home in Harrow on the Hill or Pinner?+
Yes, but these historic conservation areas carry a heritage setting and long views the council protects closely, so permitted development is often restricted and a full, context-led application is required. We design to the character of the area — materials, proportions and rooflines — and evidence the heritage considerations so the submission stands up.
How long does Harrow Council take to decide?+
Harrow determines most householder applications within the statutory eight-week period once validated. The commonest delay is a validation query, so we prepare Harrow submissions to the council's checklist with correctly scaled existing and proposed drawings and a location plan to keep the application on track.
How much do planning drawings cost in Harrow?+
We work to a fixed fee agreed upfront, usually around 30% below an architect's charge for the same council-accepted drawings, with free redraws until Harrow approves. The figure depends on the scheme — a dormer loft differs from a double-storey extension — so we confirm it once we understand your project rather than billing by the hour.
Free Fixed Quote

Get your free Harrow planning assessment

Tell us your Harrow address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.