# Builders in Hillingdon Canonical URL: https://mirion.uk/areas/hillingdon/ > Extensions, loft conversions and renovations in Ruislip, Eastcote, Ickenham and Northwood, with Hillingdon's extension limits and 4-metre Article 4 rule. We carry out extensions, loft conversions and renovations in the north of Hillingdon borough, in Ruislip, Eastcote, Ickenham and Northwood, where most homes are 1930s houses with gardens. Hillingdon's own Local Plan notes that many houses in the borough have a distinctive 1930s character, built to standard designs that give streets a consistent density and appearance. In the north of the borough, that character came with the Metropolitan Railway: the line to Uxbridge opened through Ruislip and Eastcote in 1904, and Ickenham got its halt in 1905, turning villages into Metro-land suburbs. Hillingdon has the highest share of houses of any borough we cover. At the 2021 Census, 69% of its 109,200 households lived in houses: 35% semi-detached, 20% terraced and 14% detached. The common projects are single-storey rear extensions, side extensions, rear dormer loft conversions and whole-house renovations. Because so many houses share the same design, Hillingdon's policies put strong emphasis on extensions staying subordinate to the original house. Hillingdon sets its householder rules in policy DMHD 1 of its [Local Plan Part 2](https://www.hillingdon.gov.uk/media/3084/Hillingdon-Local-Plan-Part-2-Development-Management-Policies/pdf/LPP2_Development_Management_Policies_-_ADOPTED_VERSION_JAN_2020_1.pdf) \(2020\), rather than a separate design guide. Two features matter for almost every project: - **A borough-wide [Article 4 direction](https://pre.hillingdon.gov.uk/planning-policy/article-4-directions/6)**, in force since 22 September 2014, removes permitted development rights for rear extensions projecting more than 4 metres beyond the original rear wall, so the 6-metre and 8-metre prior approval depths used elsewhere aren't available. - **Firm depth limits:** single-storey rear extensions to terraced or semi-detached houses should not exceed 3.3 metres on plots up to 5 metres wide or 3.6 metres on wider plots, and 4 metres on detached houses. The borough has 31 conservation areas, including Ruislip Village, Eastcote Village, Ickenham Village and Northwood Town Centre, plus Areas of Special Local Character such as the Copse Wood and Gatehill Farm estates in Northwood. They are listed on the [council's conservation pages](https://pre.hillingdon.gov.uk/conservation-heritage-assets/conservation-areas/4). Building work in Hillingdon: common questions What is Hillingdon's Article 4 direction on rear extensions? Since 22 September 2014, a borough-wide Article 4 direction has removed permitted development rights for rear extensions projecting more than 4 metres beyond the original rear wall. Anything deeper needs a full planning application, judged against policy DMHD 1. Does Hillingdon allow hip-to-gable loft conversions? Policy DMHD 1 says the council will not support proposals to convert a hipped roof to a gable, and roof extensions should be on the rear only and no wider than two-thirds of the roof. Where a house keeps its permitted development rights, a hip-to-gable may still be possible without an application. Which parts of Hillingdon do you cover? We concentrate on Ruislip, Ruislip Manor, Eastcote, Ickenham and Northwood in the north of the borough. - Local planning authority: London Borough of Hillingdon - Postcode districts: HA4, HA5, HA6, UB10 - Work Mirion has carried out here: Extensions, loft conversions and renovations ## Pages - [House extensions in Hillingdon](https://mirion.uk/areas/hillingdon/extensions/index.md): Rear, side and two-storey extensions in Hillingdon under policy DMHD 1: plot-width depth limits, heights, set-backs and the borough's 4-metre Article 4 rule. - [Loft conversions in Hillingdon](https://mirion.uk/areas/hillingdon/loft-conversions/index.md): Loft conversions in Hillingdon: rear-only roof extensions, the two-thirds width rule, hip-to-gable limits and traditional dormers in conservation areas. - [Home renovations in Hillingdon](https://mirion.uk/areas/hillingdon/renovations/index.md): Renovating 1930s houses in Ruislip, Eastcote, Ickenham and Northwood: layouts, services, front gardens, conservation areas and protected trees. - [Builders in Ruislip](https://mirion.uk/areas/hillingdon/ruislip/index.md): Extensions, loft conversions and renovations in Ruislip and Ruislip Manor, HA4, with Hillingdon's 3.6-metre rear extension limit and local conservation areas. - [Builders in Eastcote](https://mirion.uk/areas/hillingdon/eastcote/index.md): Loft conversions, extensions and renovations in Eastcote, HA5: 1930s semis, three conservation areas and Hillingdon's rear extension and roof limits. - [Builders in Ickenham](https://mirion.uk/areas/hillingdon/ickenham/index.md): Extensions, loft conversions and renovations in Ickenham, UB10: detached and semi-detached houses on the old Swakeleys estate and Hillingdon's planning rules. - [Builders in Northwood](https://mirion.uk/areas/hillingdon/northwood/index.md): Extensions, loft conversions and renovations in Northwood, HA6, including the Copse Wood and Gatehill estates, conservation areas and Hillingdon's limits.