Architects in HA5

Pinner, Hatch End and Eastcote. Interwar semi-detached and detached houses, several conservation areas, and the old village in Pinner.

RIBA Chartered Practice · ARB-registered architects · Extensions, lofts and planning drawings

Planning authority

Which council decides in HA5?

HA5 is split between 2 councils, so the council that decides your application depends on your street. 1,090 postcodes, 7.6 miles from our studio.

Council	Share of HA5 postcodes
Harrow	76% (828)
Hillingdon	24% (262)

Sector	Postcodes	Council
HA5 1	186	Harrow (mostly; some streets in another council)
HA5 2	215	Hillingdon (mostly; some streets in another council)
HA5 3	267	Harrow (mostly; some streets in another council)
HA5 4	229	Harrow
HA5 5	176	Harrow
HA5 9	17	Harrow

Postcode checker

Type any postcode in the 33 London boroughs we cover. We'll tell you which council handles planning there and show you the local planning points.

Local planning points

The Residential Design Guide SPD (2010) sets no fixed depth for single-storey rear extensions that need permission. Extra depth is expected to be set in from the side boundary by twice that depth.
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Two-storey rear extensions must meet the 45-degree code and are generally not possible on mid-terraced houses.
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The Harrow Local Plan 2021–2041 was adopted on 24 March 2026, replacing the 2012 Core Strategy and 2013 development management policies.
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Local planning points

Householder extensions are assessed against Local Plan Part 2 policy DMHD 1, Alterations and Extensions to Residential Dwellings (adopted January 2020).
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Converting a house into flats needs an original internal floor area of at least 120 sq m, one unit per floor, and no more than 10% of a street converted (policy DMH 4).
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A borough-wide Article 4 direction has required planning permission for small HMOs since 11 December 2025.
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Local work

Services

Nearby postcode districts: HA2, HA6, HA4, HA1, HA3, HA7.