Estiquote

Local costs · West Midlands · September 2026

How much does an extension cost in Birmingham?

A mid-range 25 m² single-storey extension in Birmingham costs about £61,000 to £75,500 including VAT, or £2,400 to £3,000 per m² at West Midlands prices. Birmingham charges £957 for building control on a 10 to 40 m² extension (full plans, including VAT): 14% above the typical council (£840). With design, a structural engineer, building control and a 15% contingency, budget £76,500 to £99,000.

By Estiquote · Prices reviewed · Council fees from Birmingham's published schedule · How we calculate

Work out your project in Birmingham

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Typical prices in Birmingham

Mid-range finish, West Midlands prices, including VAT. The budget adds design and engineering fees, Birmingham's building control charge and a 15% contingency.
ProjectBuilding workBudget to plan for
Single-storey extension, 25 m²£61,000 to £75,500£76,500 to £99,000
Double-storey extension, 40 m²£88,500 to £112,000£109,000 to £143,000
Dormer loft conversion, 30 m²£54,500 to £67,500£68,000 to £87,500
Kitchen, medium£8,900 to £15,800£10,200 to £18,100
Bathroom refit£5,900 to £8,800£6,800 to £10,200

Building prices in West Midlands run about 3% below the UK average outside London. Kitchens and bathrooms vary less from place to place than extensions and lofts.

Building control fees in Birmingham

Birmingham council charges including VAT (plan and inspection combined)
WorkCharge
Extension up to 10 m² (full plans)£752
Extension 10 to 40 m² (full plans)£957
Larger extension, 40-60 m² (full plans)£1,201
Extension 10 to 40 m² (building notice)Not published
Loft conversion up to 40 m²£752
Garage conversion£667

Birmingham charges £957 for building control on a 10 to 40 m² extension (full plans, including VAT): 14% above the typical council (£840). Source: Birmingham's building control charges, Not stated (page modified 9 January 2026). Inc VAT ("All charges include VAT at 20%").

Private approved inspectors set their own prices and are often competitive, so it is worth asking one or two for a quote as well. See how Birmingham compares with every council we checked.

Notes on Birmingham's schedule

Schedule published by Acivico (Building Consultancy) Ltd, wholly owned by and agent for Birmingham City Council.

Planning

If your extension needs planning permission, a householder application in England costs £548. Many single-storey rear extensions are permitted development and need no application, and a lawful development certificate (£274) confirms it.

Other councils in West Midlands

Building control for a 10 to 40 m² extension:

Questions people ask

How much does an extension cost in Birmingham?

A mid-range 25 m² single-storey extension in Birmingham costs about £61,000 to £75,500 including VAT for the building work, or £2,400 to £3,000 per m², based on West Midlands prices reviewed in September 2026. With fees and a 15% contingency, budget £76,500 to £99,000.

How much is building control in Birmingham?

Birmingham charges £957 (including VAT) for a 10 to 40 m² extension (full plans), according to its published schedule (Not stated (page modified 9 January 2026)).

How much does a loft conversion cost in Birmingham?

A mid-range 30 m² dormer loft conversion in Birmingham costs about £54,500 to £67,500 including VAT for the building work, and about £68,000 to £87,500 with fees and a 15% contingency.

Before you get quotes