L-shaped dormer drawings in Greenwich

A lower grant rate, and what it means for the L

In its latest year Greenwich decided 624 householder applications and granted 77.1 per cent, with 94.2 per cent decided in time.

That does not forecast any single case. It does tell us that drawings should be complete on submission, with the roof junction, the volume calculation and the street views included, so the officer has no reason to ask for more.

Heritage entries and plan age

Historic England lists 540 entries here, and the adopted plan is the Royal Greenwich Local Plan: Core Strategy with Detailed Policies, from 2,014. We read its policies alongside any newer guidance the council has used on recent roof decisions.

Owners of listed houses need listed building consent in addition to planning permission, which is a separate application and a separate set of drawings.

Houses, gardens and what they cost

Domestic gardens make up 23.2 per cent of borough land and the average home sells for 462,589 pounds, a change of -1.4 per cent over twelve months. Owners weigh a bigger loft against a move.

Greenwich has many terraced homes from the Victorian and interwar periods, some with the rear outrigger an L-shaped dormer needs. We survey first and tell you if a plain dormer would serve better.

Permitted development in the borough

Outside protected land the limit is 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume, and the height rule is: No part higher than the highest part of the existing roof. Where the L joins a rear extension, Eaves-retention and 0.2 m set-back do not apply where the enlargement joins the original roof to the roof of a rear or side extension.

Greenwich logged 437 lawful development certificate applications in the latest national return, so this route is well used. A certificate on our drawings records that your roof fell within the limit.

Views, materials and the detail officers notice

In a place with strong views, materials draw attention. A dormer clad in a colour that matches the slate or tile around it disappears in the long view; a pale or shiny cladding does not. We specify the cheek and face materials on the elevation, with a sample note, so the choice is clear before the decision is made.

We also keep the window head heights in line with the floor below and align the dormer windows with the openings under them. Officers read that alignment as a sign of care.

Terraces near the river and the park

Homes close to the river or the park often sit on sloping ground, which raises one end of the terrace above the next. A dormer that looks modest on a flat site can appear tall from the downhill side. We draw the roof against the neighbours' ridge levels so the height relationship is shown, and adjust the L if the view from below is the problem.

What happens after the survey

We send a feasibility note that says whether your address is inside the heritage site, a conservation area or neither, and what that means for the route. It includes a rough layout of the rooms an L would give, and an honest view on whether a plainer dormer would do the job with less risk.

If you go ahead, the full set follows within about a week of the survey, with the street views and the volume calculation drawn up for the council.

We also keep a record of the photographs and measurements, so if the council raises a point about height or materials months later we can answer from the original survey instead of returning to the roof.

Structure, notices and next pages

Neighbours receive notice when you cut a shared structure: Party structure notice at least 2 months before work. The stair needs this headroom: Loft conversions where 2.0 m cannot be achieved: 1.9 m at the centre of the stair, 1.8 m at the side (half width).

Every set is checked by a second MCIAT chartered technologist, and we redraw at no charge until approval. See loft conversion drawings in Greenwich, house extension drawings in Greenwich, or the Greenwich architectural drawings hub.