Two-storey and first-floor extensions in Barnet
Barnet approved 720 of the 1,042 planning applications for two-storey and first-floor extensions it decided in the last five years (69%), and the typical decision took 56 days.
London Borough of Barnet · planning applications received Oct 2021 to Oct 2026 · updated 25 Oct 2026
Approved
720 of 1,042
69% of decided applications; 81 withdrawn, 119 undecided
Typical time to a decision
56 days
median, from 1,041 decisions with both dates published
Decided within 8 weeks
601 of 1,041
8 weeks is the usual statutory period; councils can agree extensions
See what was approved near your own address
The The Signal Report shows approvals and refusals for two-storey and first-floor extensions within 250 m, 500 m and 1 km of your home, the council's reasons for refusing similar schemes, your property's planning history and the constraints on the plot. Free preview for any address.
Recent decisions
Part single, part two storey side and rear extension following the demolition of existing chimney stack and ground floor additions. Roof ex…
26/3171/HSE · decided 23 Oct 2026
- Approved8 Fernside Avenue London NW7 3BD
Part single, part two storey side and rear extensions. Replacement of existing rear dormer window.
26/2865/HSE · decided 23 Oct 2026
Roof extension including hip to gable, rear dormer window, and pitch roof over existing two storey flat roofed side extension with 3no. fro…
26/3179/HSE · decided 23 Oct 2026
Second floor extension over the existing first floor outrigger. Addition of privacy screening to first floor rear terrace
26/2930/HSE · decided 21 Oct 2026
Enlargement of basement/lower ground floor, Part single, part two storey side/rear extensions. Conversion of garage into habitable space, i…
26/3102/HSE · decided 19 Oct 2026
Why Barnet refuses two-storey and first-floor extensions
The council's own words, quoted from recent decision notices.
Tenterden Lodge Tenterden Grove London NW4 1SY
“1 Insufficient ecological and Biodiversity Net Gain (BNG) information has been submitted to enable the Local Planning Authority to fully assess the impact of the proposal on biodiversity and protected species. In particular, the absence of a Preliminary Roost Appraisal and a Biodiversity Net Gain Assessment and statuary metric prevents a determination of compliance with Biodiversity Net Gain requirements. As such, the proposal fails to demonstrate compliance with relevant biodiversity legislation and planning policy contrary to Policy G6 of the London Plan (2021) and Policy ECC07 of the Barne…”
“1 The proposed upward extension, by reason of its excessive height, scale, bulk and massing, would result in a visually dominant and discordant form of development that would fail to respond appropriately to the site's role as a transitional area between the higher-density mixed-use development fronting Hendon Way and the lower-scale suburban residential character of Allington Road. The proposal would erode the established hierarchy of building heights and cause unacceptable harm to the character and appearance of the area. The development would therefore be contrary to Policy CDH01 of the Ba…”
Sabie House 121 Marsh Lane London NW7 4LG
“1 The proposed development, by reason of its cumulative design approach, architectural form, scale, massing, extensive areas of glazing, roof design, glazed link, terracing, retaining structures, landscape engineering operations and associated material palette, would appear as an unduly incongruous and visually intrusive form of development that fails to respond sensitively to the character, appearance and architectural identity of the existing dwelling or its surrounding context. The proposal would fundamentally alter the established relationship between the dwelling and its landscape settin…”
Other home extensions in Barnet
- Loft conversions
625 of 900 approved (69%)
- Single-storey rear extensions
1,010 of 1,249 approved (81%)
- Single-storey side extensions
217 of 246 approved (88%)
How these figures are made
Planning applications London Borough of Barnet received Oct 2021 to Oct 2026, from the council's public planning register as collected by Planning Signal. An application counts as a two-storey extension when its own description says so (rules-based classification, tested against blind labelled samples). Duplicate records of one application are counted once. The approval figure counts approved and refused planning applications only: withdrawn and undecided ones, lawful development certificates and prior approvals are left out. Decision times use the received (or validated) date and the decision date the council published.
Past decisions describe what happened to other applications. They are not a prediction for yours: every application is decided on its own design and the council's current policies.