Hayling Island · Hampshire

Extensions over a garage in Hayling Island

Our extensions over a garage service in Hayling Island covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.

Before you start in Hayling Island, here's what applies.

Postcode districts
PO11
County / area
Hampshire, England
Price region
South East England
Guide price
£34,500–£50,500 (£1,930–£2,800 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
South Hayling (0.5 miles), Emsworth (4.6 miles), Havant (5.1 miles)
Distance to Southampton
about 20.7 miles
First visit
Free, no obligation

About an extension over a garage

An extension over a garage suits you if you have an attached single garage beside the house and need an extra bedroom or a larger main bedroom with an en-suite. You get an inspection of the garage structure, a design that matches the house, the approvals your nation needs, structural design, building regulations approval and the build, carried out by vetted teams working under S&K.

Around Hayling Island we also work in South Hayling, Emsworth and Havant, and across the rest of Hampshire. Postcode district in and near Hayling Island: PO11.

What it costs in Hayling Island

A guide price for Hayling Island: around £34,500–£50,500 for 3 m × 6 m of new first-floor space (18 m²). That works out at £1,930–£2,800 per m² of new floor space, including VAT at 20%. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

SpecPer m²3 m × 6 m of new first-floor space (18 m²)
Essential£1,770–£2,580 per m²£32,000–£46,500
Standard£1,930–£2,800 per m²£34,500–£50,500
Premium£2,310–£3,370 per m²£41,500–£60,500

Planning and building regulations in Hayling Island

In England, most garages sit beside the house, so building over one makes a two-storey extension beyond a side wall, which always needs planning permission. If the garage is at the rear, the 3 m and 7 m rules for two-storey rear extensions apply, measured from the original house. A householder application costs £548 (or £575 for applications made from 8 December 2026).

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Hayling Island homes

Garage walls and the door opening

Garage walls are often a single skin of brick or block with piers, and the wide door opening needs a beam over it. Many over-garage extensions need new inner walls or a steel frame to carry the floor and to insulate properly, which we confirm before the design is fixed.

Matching the house

A room over a garage usually sits beside the front of the house in full view, so roof form, ridge height, windows and brick matter. Setting the front wall and ridge back slightly from the main house usually helps it look as if it belongs.

How we'd run your project

  1. Measure and listen

    A visit to Hayling Island to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Structure and building control

    A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.

  4. Build it

    The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about extensions over a garage in Hayling Island

Which postcodes do you cover around Hayling Island?

We cover Hayling Island (PO11) and nearby places including South Hayling, Emsworth and Havant, plus the rest of Hampshire. The first site visit is free.

Do I need planning permission for an extension over a garage in Hayling Island?

Hayling Island is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How much does an extension over a garage cost in Hayling Island?

Our guide for South East England, which covers Hayling Island, is £1,930–£2,800 per m² including VAT. A typical project with 3 m × 6 m of new first-floor space (18 m²) comes to about £34,500–£50,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Can my garage take a room on top?

Sometimes, but it needs checking. Many garages are built on shallow footings with thin walls, designed only for a single storey. We dig a trial hole and inspect the walls, and the structural engineer decides whether to reuse them, strengthen them, underpin the footings or build new foundations inside the garage.

Do I need to convert the garage as well?

No. You can keep the garage for parking or storage and build only the room above, as long as the floor between them and any door into the house meet fire separation rules. Converting the garage at the same time is often good value, because the walls and foundations may be upgraded anyway.

Nearby

Close to Hayling Island? We work across the area, including:

Other extensions in Hayling Island

All two-storey extension services in Hayling Island · Extensions over a garage across Hampshire

Want a figure first? Try our guide price tool, then book a free visit to firm it up.

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