London Borough of Barnet

Adopted Documents We Assess Against

Development plan: Barnet Local Plan

Documents are re-checked against the council's own website weekly. A detected change flags "Policy Update Available" for human review — live assessment standards are never replaced automatically.

London Borough of Barnet standards at a glance

5 numeric standards taken from London Borough of Barnet's own adopted documents, each shown with the paragraph it comes from. Figures differ between councils — these are this one's.

Rear extension depth

up to 3m

For a terraced house in Barnet, a single-storey rear extension is normally expected to stay within about 3 metres of the original rear wall. Residential Design Guidance SPD paragraph 14.21

up to 3.5m

For a semi-detached house in Barnet, a single-storey rear extension is normally expected to stay within about 3.5 metres of the original rear wall. Residential Design Guidance SPD paragraph 14.21

up to 4m

For a detached house in Barnet, a single-storey rear extension is normally expected to stay within about 4 metres of the original rear wall. Residential Design Guidance SPD paragraph 14.21

Side extension form

at least 1m

A two-storey or first-floor side extension in Barnet should normally leave at least 1 metre between the extension and the boundary, so there is a 2 metre gap between the flank walls of neighbouring houses. Residential Design Guidance SPD paragraph 14.17

Roof form

at least 1m

Keep the dormer at least 1m in from the side of the roof. Residential Design Guidance SPD paragraph 14.33

Standards are what the council normally expects, not a guarantee. A scheme outside them can still be approved on its merits, and one inside them can still be refused for another reason.

Authored Policy Library

8 local policy checks, each citation-locked to the adopted document. National policy (NPPF, national space and daylight standards) applies alongside these.

Supplementary Planning Document: Residential Design Guidance

• Residential Design Guidance SPD paragraph 14.21 — Rear extension depth (3 checks) For a terraced house in Barnet, a single-storey rear extension is normally expected to stay within about 3 metres of the original rear wall. For a semi-detached house in Barnet, a single-storey rear extension is normally expected to stay within about 3.5 metres of the original rear wall. For a detached house in Barnet, a single-storey rear extension is normally expected to stay within about 4 metres of the original rear wall.
• Residential Design Guidance SPD paragraph 14.17 — Side extension form A two-storey or first-floor side extension in Barnet should normally leave at least 1 metre between the extension and the boundary, so there is a 2 metre gap between the flank walls of neighbouring houses.
• Residential Design Guidance SPD paragraph 14.23 — Two storey rear In Barnet, a two-storey rear extension that sits within 2 metres of your neighbour's boundary and projects more than 3 metres is unlikely to be supported - that combination is treated as too bulky and overbearing.
• Residential Design Guidance SPD paragraph 14.33 — Roof alterations A rear dormer in Barnet should sit clear of the ridge and the roof hips, and on semi-detached or terraced houses should normally be set in at least a metre from the party wall or chimney.
• Residential Design Guidance SPD paragraph 14.33 — Roof form Keep the dormer at least 1m in from the side of the roof.
• Residential Design Guidance SPD paragraph 14.3 — Design character You are proposing three or more separate additions at once. Barnet say plainly that a scheme can meet every individual guideline in their SPD and still be refused on its combined bulk - so show the house as it will finally look, in one set of elevations, rather than element by element.