Double-storey extensions in Castle Bromwich

What should you know before starting in Castle Bromwich?

Planning permission from Solihull Council is the first hurdle for most double-storey extensions in Castle Bromwich. Householder applications have an eight-week target for a decision, and Building Regulations approval and the Party Wall Act may also apply.

New first-floor bedrooms normally need an escape window with at least 0.33 m² of clear openable area.
Party wall notices take one or two months to run, so they're best served as soon as planning is granted.
A side extension of more than one storey always needs a householder planning application.

Postcode district: B36
Planning and building control: Solihull 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 side extension

Built over the side of the house, often where a driveway or old garage sits. It can create a garage, utility or study downstairs with a double bedroom above. Councils often expect the upper floor to be set back from the front and the roof to sit lower than the main ridge, so the design needs care to win approval.

Guide prices for Castle Bromwich

Prices in Castle Bromwich match the rest of our area: £52,000–£135,000 depending on size and specification. A two-storey side extension on a three-bed semi, about 32 m² over two floors: usually £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.

Before you book in Castle Bromwich

Can we stay in the house while you build?

Most families do. The early stages are outside, and the existing house stays closed off until the shell is weathertight. The harder weeks are when openings are cut through on both floors, which brings dust and noise into bedrooms and the kitchen. We sheet off openings, lock up securely every night and agree in advance which rooms you'll lose and when.

How do I book a survey in Castle Bromwich?

Send the form on this page, use the guide-price tool or call 0800 088 6248 free. We'll ask a few questions about your two-storey extension and arrange a time to visit.

How much does a double-storey extension cost?

In the West Midlands, most double-storey extensions cost between £52,000 and £135,000, including VAT where it applies. A typical side extension on a three-bed semi, around 32 m² across both floors, usually costs £68,000–£88,000 built to a plastered finish. Kitchen units, a bathroom suite, flooring and decorating are priced separately, so you can choose them to suit your budget.

Will I need permission from the council in Castle Bromwich?

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

Double-storey extensions near Castle Bromwich

Other home improvements in Castle Bromwich

Let's talk about the space you need; a written, itemised quote for your Castle Bromwich home costs nothing and commits you to nothing.