Planning and building regulation drawings in Forest Hill (SE23)

That gradient is what homeowners here end up designing around. A rear extension on a level Victorian terrace elsewhere in London is a fairly routine drawing exercise; on a Forest Hill hillside plot, the same brief has to account for changing ground levels, a neighbour's outlook from above or below, and foundations that step down the slope rather than sit flat. Loft conversions face a similar wrinkle, since roofline changes on a hill are visible from much further away than on flat streets, which tends to sharpen how a council looks at them. Add mature trees, some carrying preservation orders, especially near the Horniman gardens, and a straightforward loft or rear-return project can pick up two or three extra layers of consideration before a drawing is ready to submit. None of that makes the work impossible; it just means the survey and the design need to happen in the right order.

Much of Forest Hill also sits inside a conservation area, which changes what's routine and what needs a fuller planning application before anything gets built.

Planning in Forest Hill: what to know before you apply

Lewisham runs its planning service borough-wide, but Forest Hill carries a conservation area designation with its own Article 4(3) direction attached, which strips out some of the permitted development rights a homeowner might expect on an ordinary terrace elsewhere in the borough. In practice, that means changes many owners assume are automatic, like a side extension or certain window replacements, can require a full planning application here even when an identical project a few streets outside the boundary wouldn't. There's a separate small-HMO direction covering part of the district too, aimed at new houses in multiple occupation rather than family extension work, but worth knowing about if a property's use is ever in question. Lewisham also expects proposals near the Horniman gardens and other tree-covered plots to account for preservation orders from the outset, not as an afterthought once drawings are already submitted. We check the designation and any Article 4 status on a specific street before starting a design, because assuming permitted development rights apply in Forest Hill is one of the more common ways a project loses time.

Applications are decided by London Borough of Lewisham — its planning pages.