Double-storey extensions in Streetly

Before your two-storey extension in Streetly

Most two-storey extensions in Streetly need a planning application to Walsall Council. A two-storey rear extension can sometimes be permitted development, but only if it is no more than 3 m deep and at least 7 m from the rear boundary, among other conditions. Building Regulations approval is needed either way.

The householder planning fee in England is £548 from April 2026, paid to Walsall Council when you apply.
An upstairs en-suite is simplest when the new bathroom sits close to the existing soil stack.
Party wall notices take one or two months to run, so they're best served as soon as planning is granted.

Postcode district: B74
Planning and building control: Walsall Council
From our West Bromwich base: 6 miles

Which options suit homes in Streetly?

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.

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.

How much should you budget in Streetly?

For a home in Streetly, 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. Access, parking and the state of what's there now can move the price — the survey settles it.

Before you book in Streetly

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.

How do I book a survey in Streetly?

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.

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.

Does Walsall Council need to approve my two-storey extension?

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

Close to Streetly

Other work we do in Streetly

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