Flat conversion drawings in Harrow

How strictly Harrow treats small schemes

In the latest twelve months Harrow decided 341 minor applications, granted only 60.4 per cent, and decided 85.6 per cent on time. Compare 81.7 per cent for householder work: a conversion is judged much harder than an extension.

Harrow is also strict on a related route. Of the larger-home extension prior approvals it decided, 108 were refused against 27 granted. Detailed drawings matter here.

Housing, gardens and Green Belt in Harrow

65.4 per cent of households live in a house, and domestic gardens covered 34.7 per cent of the borough's land. A terraced house averages about £536,748; a flat about £317,917.

Green Belt covers 22 per cent of the borough and there are 31 conservation areas. Harrow has an Article 4 direction for HMOs too. See architectural drawings in Harrow for the list.

Levy, fee and sound

Harrow's borough levy is flat: £196.43/m² (Residential, Use Class C3, borough-wide) Mayoral CIL band 2 adds £72.73 per square metre indexed. The council fee is £610 per flat.

Sound separation follows Approved Document E (Separating walls 43 dB DnT,w+Ctr (min); floors and stairs 43 dB airborne (min), 64 dB L'nT,w impact (max) for dwellings formed by material change of use), drawn in the building regulations drawings. A second chartered technologist checks every sheet.

Which Harrow houses pass the garden test

Mid-terrace houses are excused from the private-garden expectation, which makes them oddly attractive: a Harrow terraced house averages about £536,748, and the garden division is not required. Semi-detached and detached houses are not excused, but they bring the garden to split. A semi-detached house averages about £663,954 and a detached about £1,206,272.

The borough's 89,642 households are mostly owner-occupiers, at 58.8 per cent, so a family house on a good street has strong resale value, and it is worth checking that conversion adds more than it costs. Detached houses tend to give the best split because side access is already there.

A last point on tactics. Because minor applications are granted at a lower rate than householder ones, some owners start with a smaller scheme, such as a rear extension that makes the ground-floor flat larger, before applying for the split. Our rear extension drawings in Harrow page covers that sequence, and prior approval drawings in Harrow cover larger home extensions where they apply.

Daylight, privacy and the split garden in Harrow

A divided garden creates two new relationships. The lower flat sits closest to the new boundary, so its windows need daylight and a screen that does not feel enclosing, and the upper flat needs a route to its garden that does not run through the lower flat. We draw the fence line, the path and the planting, and test daylight on the sections.

Privacy is the other test. Overlooking between the two plots and into neighbours is a common reason for refusal, and the drawings show obscure glazing, window positions and screening in detail. A second chartered technologist checks each sheet before submission, and we deal with the case officer after it.

It is also worth deciding early who will own and manage the two flats. If you plan to sell the upper flat on a long lease, the garden split, the shared hall and the bin store all need to be described clearly, and our lease plans page explains the plans that go with that sale.