Hornchurch and Upminster semis: basements in Havering

Which Havering postcodes does this basement extension service cover?

Every Havering postcode district we draw in, the stock that dominates it and the authority that validates a basement extension there. Havering fees below are the statutory England rates for 2026, not basement extension estimates.

How does a basement extension differ street by street across Havering?

Roof pitch, wall build-up and plot depth change every few Havering streets, and each one changes what a basement extension can achieve at that address.

• Romford (RM1, RM2, RM7) — Victorian and post-war centre defines Romford, where victorian terraces, 1930s semi-detached, post-war flats set what a basement extension can do. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged across RM1. Any Romford basement extension is validated by Havering Council, with Romford Market the usual Romford reference point on the site plan.
• Hornchurch (RM11, RM12) — 1930s semi-detached defines Hornchurch, where 1930s semi-detached set what a basement extension can do. 1930s houses were built without cellars across RM11. Any Hornchurch basement extension is validated by Havering Council, with Hornchurch Tube the usual Hornchurch reference point on the site plan.
• Upminster (RM14) — basement extension work in Upminster means 1930s semi-detached, edwardian villas. Upminster is 1930s semi-detached, Edwardian villas. Edwardian houses rarely have a usable cellar throughout RM14. Havering Council decides the Upminster application, and Upminster station anchors the Upminster location plan.
• Rainham (RM13) — a basement extension in Rainham starts from 1930s semi-detached, and Rainham reads as 1930s semi-detached, village fragments. 1930s houses were built without cellars in RM13. Havering Council assesses Rainham basement extensions against its own Rainham character guidance, and the location plan we draw for Rainham references Rainham Village.
• Harold Hill (RM3) — basement extension work in Harold Hill means post-war estate. Harold Hill is post-war estate. Post-war slab foundations make basements here expensive and rarely viable throughout RM3. Havering Council decides the Harold Hill application, and Harold Hill anchors the Harold Hill location plan.
• Collier Row (RM5) — 1930s semi-detached, post-war defines Collier Row, where 1930s semi-detached set what a basement extension can do. 1930s houses were built without cellars across RM5. Any Collier Row basement extension is validated by Havering Council, with Collier Row Road the usual Collier Row reference point on the site plan.
• Elm Park (RM12) — 1930s semi-detached defines Elm Park, where 1930s semi-detached set what a basement extension can do. 1930s houses were built without cellars across RM12. Any Elm Park basement extension is validated by Havering Council, with Elm Park Tube the usual Elm Park reference point on the site plan.

How do conservation areas and Article 4 affect a basement extension in Havering?

How designation changes a Havering basement extension: Havering Council maintains 15 conservation areas, including Rainham Village, Romford Market, Upminster. Inside any of them a Havering basement extension cannot rely on permitted development, and the route becomes a £548 householder application determined in 8 weeks rather than a £249 prior approval in 6 weeks. Hornchurch sets the tone for Havering casework.

Havering permitted development status: there is no borough-wide direction from Havering Council, so a basement extension at a RM1 address is normally still permitted development. We certify that with a £274 Lawful Development Certificate rather than leaving a Havering sale to argue it later.

The building fabric around Havering: 1930s semi-detached dominates Hornchurch and Upminster; post-war in Harold Hill and Romford; Victorian in older Romford centre. Outer east London; Metropolitan Green Belt covers north of the borough; permissive residential planning; strong PD use. A basement extension in Havering is scoped against that stock first.

What happens if a Havering property sits on a boundary?

• Barking and Dagenham — cross the Havering boundary and Barking and Dagenham Council takes the basement extension instead, applying 9 conservation areas of its own around IG11. We re-price basement extensions at the Havering edge because Barking and Dagenham policy and Havering policy rarely align on basement extension depth.
• Redbridge — the Redbridge boundary runs against Havering, so a basement extension a street from Havering is decided by Redbridge Council instead. Redbridge runs 14 conservation areas across E11 and its neighbours, which is why basement extensions priced for Havering are re-checked against Redbridge policy whenever the Havering address sits on that edge.

Sources for this Havering basement extension page: borough policies maps and conservation-area registers (2025–26), Royal Mail postcode district boundaries, the Town and Country Planning (Fees for Applications) (England) Regulations, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended, and the Party Wall etc. Act 1996.