First-floor extensions in Shanklin
If you live in Shanklin and need more room without moving, a first-floor extension is worth a serious look. We handle the drawings, approvals, structure and build.
We take on projects in Shanklin by arrangement. Site visits here aren't free as standard, and we'll agree travel costs with you in writing first.
Useful details for planning a first-floor extension in Shanklin.
- Postcode districts
- PO37
- County / area
- The Isle of Wight, England
- Price region
- South East England
- Guide price
- £27,500–£40,000 (£1,980–£2,860 per m²)
- Approval route
- It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
- Nearest towns
- Sandown (1.9 miles), Ventnor (2.5 miles), Newport (Isle of Wight) (7.2 miles)
- Distance to Newport (Isle of Wight)
- about 7.2 miles
- First visit
- By arrangement
About a first-floor extension
A first-floor extension suits you if your house already has a single-storey extension and you need more space upstairs. You get a structural check of the existing walls and foundations, a design that ties the new floor into the house, the approvals your nation needs, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.
Around Shanklin we also work in Sandown, Ventnor and Newport (Isle of Wight), and across the rest of the Isle of Wight. Postcode district in and near Shanklin: PO37.
What it costs in Shanklin
For budgeting in Shanklin, allow around £27,500–£40,000 for a first-floor extension with 4 m × 3.5 m of new first-floor space (14 m²). That's based on £1,980–£2,860 per m² including VAT for South East England. Design fees, structural calculations and approval fees are separate and listed on our prices page.
| Spec | Per m² | 4 m × 3.5 m of new first-floor space (14 m²) |
|---|---|---|
| Essential | £1,820–£2,630 per m² | £25,500–£37,000 |
| Standard | £1,980–£2,860 per m² | £27,500–£40,000 |
| Premium | £2,380–£3,430 per m² | £33,500–£48,000 |
Planning and building regulations in Shanklin
In England, adding a first floor turns a single-storey extension into one of more than one storey. To be permitted development, the extension as a whole must go no more than 3 m beyond the rear wall of the original house and stay at least 7 m from the rear boundary, with matching materials and roof pitch. Over a side extension it always needs planning permission, costing £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 Shanklin homes
Escape and fire safety
A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and 450 mm high, with the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs.
Matching the roofline
A first-floor extension often changes how the back or side of the house looks more than the original single storey did. Matching the main roof pitch and materials, and keeping the ridge below the main ridge, usually gives the best result and is expected for permitted development in England.
How we'd run your project
Visit by arrangement
We agree a visit to your home in Shanklin and any travel costs with you in writing first, then look at the structure, access and boundaries.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Detail and price
Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.
Build and sign-off
Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.
Questions about first-floor extensions in Shanklin
Which postcodes do you cover around Shanklin?
We cover Shanklin (PO37) and nearby places including Sandown, Ventnor and Newport (Isle of Wight), plus the rest of the Isle of Wight. Visits and projects in Shanklin are by arrangement, with travel costs agreed in writing first.
How long does a first-floor extension take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.
Who handles building regulations for a project in Shanklin?
We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
Can I build on top of my existing single-storey extension?
Often yes, but only after the structure has been checked. Foundations, walls and lintels built for one storey may not carry two. We dig trial holes, look for the original building control approval and ask the structural engineer to confirm what can stay, what needs strengthening and what must be rebuilt.
Will the first-floor extension match my house?
It should, and in England matching materials and roof pitch is a condition of permitted development. We match brick, tile, mortar colour and window style where we can, and tell you at the design stage if an exact brick match is not available, so you can choose between the closest match and render or cladding.
Nearby
The same service in neighbouring towns:
Other extensions in Shanklin
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Shanklin · First-floor extensions across the Isle of Wight
The quickest next step is a visit. We'll look at your house in Shanklin and give you an honest view of the options.