
Planning Permission in Forest Hill SE23
Fixed-fee, MCIAT-chartered planning permission 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
Planning Permission for Forest Hill (SE23) homes: the package and the process
Every planning permission we prepare for an Forest Hill property is drawn to London Borough of Lewisham’s validation standards and tuned to the SE23 constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.
Securing planning permission in London means navigating borough-specific design guidance, conservation areas, Article 4 directions and a validation checklist that differs from one council to the next. DrawingsDirect prepares the existing and proposed drawings your local planning authority needs, submits them through the Planning Portal, and manages the application to a decision — for a fixed fee agreed before we start.
Because we are MCIAT-chartered architectural technologists rather than a general architecture practice, you get the same council-accepted drawings and professional accountability at a typically lower fee, with structural coordination handled in-house.
Do I need planning permission for an extension in London?
Many single-storey rear extensions, loft conversions and outbuildings fall under permitted development rights and do not need a full planning application — but London's dense housing stock, conservation areas and Article 4 directions frequently withdraw those rights. Before you pay for a full application, we check your property against the current permitted development thresholds and your borough's local constraints.
Where permitted development applies, we recommend a Lawful Development Certificate instead of full planning — it is faster, cheaper and gives you a legal document confirming the work was lawful. Where a full application is genuinely required, we prepare it properly the first time.
Permitted development vs a full planning application
Permitted development lets you build within defined volumetric limits without committee review. A full householder application is assessed against the borough's local plan for scale, daylight, neighbour impact and design. We advise which route your project qualifies for and why.
Article 4 directions and conservation areas
If your home sits in a conservation area or under an Article 4 direction, permitted development rights are often removed — meaning even modest changes need consent. Each borough page lists the local directions and conservation areas we routinely design around.
How do you apply for planning permission through the London Planning Portal?
We manage the full lifecycle of your submission — survey, drawings, supporting documents and officer liaison — so you never have to decode a validation checklist yourself.
Phase 1 — existing and proposed site surveys
A laser-measured survey captures your property exactly, so existing and proposed drawings match reality millimetre for millimetre.
Phase 2 — technical drawing package
Site location plan, block plan, floor plans, elevations and sections drawn to your borough's scale and formatting requirements, with a design and access statement where needed.
Phase 3 — liaison with the planning officer
We answer the council's queries, negotiate amendments, and redraw free until the decision lands.
| Package | Production window | Compliance layer | Typical fee |
|---|---|---|---|
| Permitted Development pack | 7–10 working days | Lawful Development Certificate submission | £950–£1,450 |
| Full Planning pack | 10–14 working days | Council liaison & design statement | £1,600–£2,400 |
| Planning + Building Regs pack | 14–21 working days | Structural calculations included | £2,200–£3,850 |
Planning Permission in Forest Hill SE23 — FAQs
How long does it take to get planning permission from a London council?+
What happens if the council refuses?+
Do you cover my borough?+
Is the fee really fixed?+
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.