Double-storey extensions in Kings Norton

Planning your two-storey extension in Kings Norton

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

Under permitted development, a rear extension of more than one storey can project no more than 3 metres and must be at least 7 metres from the rear boundary.
The householder planning fee in England is £548 from April 2026, paid to Birmingham City Council when you apply.
New first-floor bedrooms normally need an escape window with at least 0.33 m² of clear openable area.

Postcode district: B38
Planning and building control: Birmingham City Council
From our West Bromwich base: 9 miles

Choices to weigh up in Kings Norton

Mixed-height extension

A two-storey section at the side with a single-storey section running across the back. This keeps the first floor away from neighbours' windows while still giving a wide kitchen-diner below. It's a practical compromise where planners have concerns about a full-depth two-storey rear extension, and it often simplifies the roof.

Combined side and rear

An L-shaped two-storey build wrapping the side and back of the house gives the biggest gain, sometimes two extra bedrooms. It's a substantial project with more steel and a complex roof junction, and it will need a householder planning application. Expect a longer programme and a careful plan for keeping the house secure while the roofs are joined.

How much should you budget in Kings Norton?

For a home in Kings Norton, our guide range is £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. We confirm a fixed price for the agreed specification after visiting.

Your questions answered

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.

How do I book a survey in Kings Norton?

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.

What will the council look at when deciding planning?

Councils judge two-storey extensions mainly on their effect on neighbours and the street. They look at loss of light and outlook next door, overlooking from upstairs windows, and whether the extension sits comfortably with the house, often expecting side extensions to be set back and lower than the main roof. Many councils publish householder design guides, and following yours closely improves the chance of approval.

Does Birmingham City Council need to approve my two-storey extension?

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 Kings Norton

Other home improvements in Kings Norton

Call 0800 088 6248 or send us your postcode, and we'll arrange a time to look at the house.