Double-storey extensions in Walmley

Planning your two-storey extension in Walmley

Expect to apply to Birmingham City Council for planning permission for a two-storey extension in Walmley; side extensions over one storey always need it. We prepare the drawings, and the structural work also needs Building Regulations approval.

An upstairs en-suite is simplest when the new bathroom sits close to the existing soil stack.
A side extension of more than one storey always needs a householder planning application.
Scaffolding is usually up for most of the build, so think about access along the side of the house early.

Postcode district: B76
Planning and building control: Birmingham City Council
From our West Bromwich base: 9 miles

Which option fits your home?

Building over an existing extension

Adds a first floor on top of an existing single-storey extension or attached garage. It can cost less because the footprint already exists, but a structural engineer must check the existing foundations and walls first, and they sometimes need strengthening. The old flat roof comes off and the new floor is tied into the main house.

Two-storey rear extension

Adds depth to both floors across the back of the house: a kitchen-diner below and a larger bedroom or new bathroom above. Permitted development only covers projections up to 3 metres and at least 7 metres from the rear boundary, so many rear builds still need planning. Overlooking and loss of light to neighbours are the usual tests.

What does your two-storey extension cost in Walmley?

Guide prices start at £52,000 and run to £135,000 depending on size and specification. A two-storey side extension on a three-bed semi, about 32 m² over two floors: around £68,000–£88,000.

Guide prices for double-storey extensions
Option	Guide price	Good to know
Compact two-storey rear (20–28 m² total)	£52,000 – £72,000	Bigger kitchen below, bedroom or bathroom above
Two-storey side or rear (30–40 m² total)	£68,000 – £98,000	The usual size on a three-bed semi
Large or combined side and rear (45 m²+)	£95,000 – £135,000	More steel, a complex roof and a longer programme

Guide ranges include VAT where it applies. A free survey turns this guide into a fixed, itemised price.

Double-storey extensions in Walmley: common questions

Is a double-storey extension better value than a single-storey one?

Per square metre, usually yes. Foundations and roofs are the expensive parts of any extension, and on a two-storey build they serve twice the floor area. You'll pay more in total and planning is less certain, but if you need a bedroom as well as downstairs space, building both together normally costs less than two separate projects years apart.

Do you cover Walmley?

Yes. Walmley (B76) is about 9 miles from our West Bromwich base and inside the area we cover. Call 0800 088 6248 or send the form on this page to book a free survey.

What paperwork will I have at the end?

You'll get the building control completion certificate, the electrical installation certificate, your planning decision notice and the manufacturers' guarantee documents for windows, doors and roof products, with their terms set out in your quote. Keep these together, as a buyer's solicitor will ask for them when you sell. Ask us for current insurance details with your quote.

Who approves double-storey extensions in Walmley?

Usually both. Most two-storey extensions need a planning application to Birmingham City Council, and the structural work needs Building Regulations approval from its building control team or a registered building control approver.

Double-storey extensions near Walmley

Other home improvements in Walmley

Want a guide figure first? Use our quote tool for your Walmley extension, then book a survey for a fixed price for the agreed specification.