Dormer loft conversion drawings in Barking and Dagenham

The Becontree Estate and its design code

The borough includes the Becontree Estate, which has its own Becontree Estate SPD and Design Code. On a street where the roofs match, a dormer shows as a break in the pattern.

We draw the rear elevation against the neighbouring roofs and note where the code applies, because a dormer that is routine in a mixed street may need more care here.

Permitted development limits for a dormer

Under national rules a dormer can be permitted development if it stays within the volume limit: 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume. Position matters as well: No enlargement beyond the plane of a roof slope that forms the principal elevation and fronts a highway.

The set-back is stated too: Original eaves maintained; enlargement set at least 0.2 m from the eaves measured up the roof slope, so far as practicable (not required for hip-to-gable or roofs joining a rear/side extension). Materials are covered by: Exterior materials similar in appearance to the existing house. Side windows have their own condition: Upper-floor side windows obscure-glazed and non-opening below 1.7 m above floor.

If the house stays within these, a Lawful Development Certificate in Barking and Dagenham proves it. If not, a householder application follows.

Where permitted development is removed

The borough has 4 conservation areas and 3 Article 4 directions. On conservation area land the rule is firm: Class B roof enlargements are not permitted development on article 2(3) land. Historic England also lists 49 entries in the borough, and a listed house needs consent for roof alterations.

A dormer in any of those places goes through planning, drawn as in our planning drawings in Barking and Dagenham. We check your address before we price the work.

Stairs, fire and insulation

A new room needs a safe way up. Where full height cannot be achieved the guidance allows less: 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). On a modest terrace the stair, not the roof, can limit where the dormer can go.

Fire rules apply to the escape route: New storey above 4.5 m by loft conversion: protect the full escape route with fire-resisting doors (min E 20) and partitions (min REI 30). The new roof has an energy target too: New elements in existing dwellings, limiting U-values W/(m²·K): roof 0.15, wall 0.18, floor 0.18, windows 1.4 (or WER Band B), doors 1.4. We show these on the section before the dormer height is fixed, because the roof build-up adds to it.

How the council has been deciding householder applications

In its latest published year the council decided 388 householder applications and granted 66.5 per cent. The share decided on time was 100 per cent.

A grant rate at this level is a reason to meet the guidance closely. It is still a borough-wide figure for every kind of householder project, and it says nothing about one dormer.

Price, checks and what is included

Dormer loft conversion drawings start at £695, VAT included and fixed before you commit. The set has existing and proposed plans, elevations and sections, with the dormer, the stair and the roof build-up shown, plus the location and block plans. A second chartered technologist checks every sheet, and we redraw free if the council asks for changes.

Our building regulations drawings in Barking and Dagenham carry the technical detail forward.

Related drawings and neighbouring boroughs

For the wider picture, see loft conversion drawings in Barking and Dagenham, L-shaped dormer drawings or rear extension drawings in Barking and Dagenham. The borough overview is at architectural drawings in Barking and Dagenham.

The same service is covered in Redbridge, Havering and Newham. Our dormer loft conversion drawings guide sets out the national rules.