Estiquote

Local costs · North East · September 2026

How much does an extension cost in Durham?

A mid-range 25 m² single-storey extension in Durham costs about £55,500 to £68,500 including VAT, or £2,200 to £2,700 per m² at North East prices. Durham charges £743 for building control on a 10 to 40 m² extension (full plans, including VAT): 12% below the typical council (£840). With design, a structural engineer, building control and a 15% contingency, budget £69,500 to £90,500.

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

Work out your project in Durham

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Typical prices in Durham

Mid-range finish, North East prices, including VAT. The budget adds design and engineering fees, Durham's building control charge and a 15% contingency.
ProjectBuilding workBudget to plan for
Single-storey extension, 25 m²£55,500 to £68,500£69,500 to £90,500
Double-storey extension, 40 m²£80,500 to £101,000£99,500 to £131,000
Dormer loft conversion, 30 m²£49,500 to £61,000£62,500 to £80,000
Kitchen, medium£8,500 to £15,000£9,700 to £17,300
Bathroom refit£5,600 to £8,400£6,400 to £9,600

Building prices in North East run about 12% below the UK average outside London. Kitchens and bathrooms vary less from place to place than extensions and lofts.

Building control fees in Durham

Durham council charges including VAT (plan and inspection combined)
WorkCharge
Extension up to 10 m² (full plans)£496
Extension 10 to 40 m² (full plans)£743
Larger extension, 40-100 m² (full plans)£957
Extension 10 to 40 m² (building notice)£744
Loft conversion up to 40 m²£750
Garage conversion£340

Durham charges £743 for building control on a 10 to 40 m² extension (full plans, including VAT): 12% below the typical council (£840). Source: Durham's building control charges, 1 April 2026 (amended). Inc VAT ("Figures shown are Inclusive of VAT").

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 Durham compares with every council we checked.

Notes on Durham's schedule

Own schedule.

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 North East

Building control for a 10 to 40 m² extension:

Questions people ask

How much does an extension cost in Durham?

A mid-range 25 m² single-storey extension in Durham costs about £55,500 to £68,500 including VAT for the building work, or £2,200 to £2,700 per m², based on North East prices reviewed in September 2026. With fees and a 15% contingency, budget £69,500 to £90,500.

How much is building control in Durham?

Durham charges £743 (including VAT) for a 10 to 40 m² extension (full plans), according to its published schedule (1 April 2026 (amended)).

How much does a loft conversion cost in Durham?

A mid-range 30 m² dormer loft conversion in Durham costs about £49,500 to £61,000 including VAT for the building work, and about £62,500 to £80,000 with fees and a 15% contingency.

Before you get quotes