Garden Rooms in Hanwell, W7

One Council and One Answer

This sounds like a small thing and it is not. Across west London the postcode districts split between boroughs in ways that catch people out. Chiswick spans three, Acton spans three, and even the W5 Ealing district reaches into Hounslow. W7 falls wholly within Ealing.

It means one planning register, one set of guidance and one answer to any question about your address, which is more than can be said for most of the areas either side.

The Highest Share of Houses in West London

Permitted development under Part 1 applies to dwellinghouses and excludes flats and maisonettes outright, so the proportion of an area living in a whole house is the single best measure of how many people can actually use it. On that measure Hanwell leads west London.

Census 2021 puts around 62 per cent of North Hanwell ward households in a whole house, the highest figure of any ward we looked at across Chiswick, Acton, Hanwell and Ealing, and well ahead of South Acton at 18 per cent. Hanwell Broadway ward sits at about 44 per cent. North Hanwell also has the highest semi-detached share of the group at roughly a quarter of households, which is the stock most likely to have a side route to the rear.

ONS and Ordnance Survey, published April 2020, median private outdoor space for a house. The London median is 139.6 square metres.

The Brent Valley and Cuckoo Park streets come close to the London median, so a substantial building is realistic there. Central Hanwell is well below it, and there the rule limiting cover to half the curtilage becomes the design constraint. Neither is a problem, but they produce different buildings and it is better to know which you are working with before drawings start.

Hanwell has an unusual concentration of protected engineering. The Hanwell Flight of Locks raises the Grand Union Canal just over fifty three feet in a third of a mile across six locks, and the locks, their 1815 side ponds and the adjoining hospital boundary wall are a scheduled monument. Three Bridges nearby, where Brunel stacked road, canal and railway, is another, and was his last major railway project. The Wharncliffe Viaduct is Grade I listed.

For most Hanwell gardens none of this touches the project. It matters where a property backs onto the canal or sits close to one of these structures, because scheduled monument protection is a separate regime from planning and the setting of a listed structure is a material consideration in any application.

Garden Room Costs in Hanwell

Budget from around £35,000 for a bespoke build. Where the house is unlisted and the design stays inside the Class E limits, there is no application fee and no determination period, so the whole budget goes into the building. That combination of a single authority, no outbuilding Article 4 and very little listing makes Hanwell one of the simpler places in London to get a project underway.

Hanwell station is on the Elizabeth line in Zone 4, the only Zone 4 station across this part of west London, and its Grade II listed up-side building predates the modern service by a long way. Brent Lodge Park, the Village Green and the canal towpath give the area its open space, and St Mellitus and the old St Bernard's Hospital buildings anchor its listed stock. The same installers cover Ealing and Acton to the east, and Chiswick further south. For the briefs that come up most often here, see the garden office and garden gym specifications.