House Extension Cost in Birmingham: 2026 Price Guide

• Side return infill: £17,000-£28,000
• Single-storey rear extension: £24,000-£52,000
• Double-storey extension: £52,000-£95,000 upwards

Birmingham City Council manages over 30 conservation areas, a legacy of the city's rapid Victorian growth on the back of its jewellery, gun and metalworking trades - "the workshop of the world," as it was known at the height of its manufacturing era. Edgbaston's is among the largest conservation areas in the country by area, and extensions there typically need to match the scale and materials of substantial original Victorian villas.

The canal factor

It's a genuinely useful piece of local trivia that Birmingham has more miles of canal than Venice - and in practice, a small number of extension projects near the historic canal network (particularly around the Jewellery Quarter and Gas Street Basin) run into additional considerations around historic towpath access and structures, which a builder unfamiliar with the area might not anticipate.

What pushes costs up

As with most Victorian terraced cities, access on the narrower streets of Sparkhill, Balsall Heath and parts of Selly Oak is the recurring extra cost - skip and scaffold permits are often required where a residential street has no realistic space for either without blocking the road.