
New Build Drawings in Forest Hill SE23
Fixed-fee, MCIAT-chartered new build drawings for Forest Hill (SE23) homeowners — London Borough of Lewisham validation and local constraints handled from the start.
Forest Hill (SE23) in Lewisham is a hilly Victorian suburb of substantial villas and terraces around the Horniman Museum and gardens. The steep topography and the Forest Hill conservation area together shape what works for extensions and loft conversions here.
Within the conservation area an Article 4(3) direction removes specified permitted development rights, so many changes that would be permitted elsewhere need a full application designed to the area's Victorian character; the steep plots add overlooking and level-change considerations. Lewisham's small-HMO Article 4 direction is a further control on conversions.


Planning in Forest Hill (SE23): what to know before you apply
The Forest Hill conservation area carries an Article 4(3) direction removing specified householder permitted development rights, so loft and extension projects within it generally need a full planning application rather than relying on permitted development. The steep hillside plots and mature trees around the Horniman add design and TPO considerations, and Lewisham's small-HMO Article 4 direction restricts new conversions.
Typical Forest Hill housing stock
Substantial Victorian villas and terraces climbing the hills around the Horniman Museum, with later Edwardian and interwar houses on the higher ground toward Honor Oak.
Streets we regularly draw for in Forest Hill
London Road · Dartmouth Road · Honor Oak Road · Devonshire Road
What SE23 is actually built of
Measured from 377 classified residential buildings in SE23, not from a description of the area.
Forest Hill SE23 housing mix
Residential building form across the SE23 postcode district, from 377 classified buildings.
| Attached on more than one side | 50% |
|---|---|
| Attached on one side | 39% |
| Detached | 11% |
| Median building footprint | 67 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 1.8 |
| Buildings classified | 377 |
Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-08-17.
New Build Drawings for Forest Hill (SE23) homes: the package and the process
A new dwelling is a full application rather than a householder one, and the drawing set reflects that: site layout with levels and boundaries, floor plans and elevations for the new building, sections showing how it sits in the ground, and street-scene elevations placing it against what is already there.
Two packages follow the approval — the planning set and the construction set — and they have to stay in step. Foundation design, drainage strategy, thermal performance and fire strategy are drawn for Building Control against the same geometry that was granted permission, so the built house matches the approved one.
An infill plot is designed against its neighbours. Plot width, the building line either side, and the ridge heights next door set what the new house can be — and on a tight urban site those constraints usually shape the design more than the brief does.
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.
How do daylight, sunlight and overlooking affect a new build design?
London boroughs assess new dwellings against their effect on the daylight and sunlight reaching neighbouring homes and gardens, commonly using the 45-degree rule as an initial check on a proposal's massing and position relative to neighbouring windows, alongside more detailed daylight and sunlight assessment on sensitive sites. Overlooking and loss of privacy from new windows, upper floors or roof terraces are assessed similarly, and often shape decisions on window placement, floor-to-floor heights and the overall footprint and massing of the new building. Designing with these constraints from the earliest sketch stage, rather than adjusting for them after a refusal, is one of the main advantages of instructing feasibility and pre-application work before a full planning set.
| Stage | What it establishes | Typical fee guide |
|---|---|---|
| Feasibility | Whether the plot can support a new dwelling and the likely constraints | Quoted individually, from within the £2,500 new build fee |
| Pre-application advice | Written borough feedback on the scheme before a full application | Quoted individually alongside the planning fee |
| Full planning drawings | The complete drawing set submitted for planning permission | From £2,500 |
| Building regs and structural | Construction-ready drawings and calculations for building | From £2,200–£3,850, quoted once planning is settled |

New Build Drawings in Forest Hill SE23 — FAQs
How much do new build drawings cost in London?+
Can any garden or backland plot be built on in London?+
Do I need pre-application advice before a full new build application?+
Do you handle building regulations and structural drawings for a new build, or only planning?+
How long does a new build project take from feasibility to planning permission?+
Do I need planning permission for a side-return extension in Lewisham?+
What does Lewisham's borough-wide HMO Article 4 direction affect?+
Can I convert the loft on my Lewisham terrace?+
How long does Lewisham Council take to decide?+
How much do planning drawings cost in Lewisham?+
Get your free Forest Hill planning assessment
Tell us your Forest Hill (SE23) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.