Cranleigh · Surrey

Two-storey side extensions in Cranleigh

Adding a two-storey side extension in Cranleigh gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Useful details for planning a two-storey side extension in Cranleigh.

Postcode districts
GU6
County / area
Surrey, England
Price region
South East England
Guide price
£94,500–£127,000 (£2,260–£3,030 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Godalming (6.4 miles), Guildford (7.5 miles), Horsham (8.7 miles)
Distance to Woking
about 12.6 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

Cranleigh sits about 12.6 miles from Woking. Closer to home, Godalming is 6.4 miles away and Guildford 7.5 miles.

What it costs in Cranleigh

Guide prices for two-storey side extensions in South East England are around £2,260–£3,030 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £94,500–£127,000. Design fees, structural calculations and approval fees are separate and listed on our prices page.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£2,070–£2,780 per m²£87,000–£117,000
Standard£2,260–£3,030 per m²£94,500–£127,000
Premium£2,710–£3,630 per m²£113,500–£152,500

Planning and building regulations in Cranleigh

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

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 Cranleigh homes

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

How we'd run your project

  1. Visit and first ideas

    One of our team visits your house in Cranleigh, checks the walls, roof and drains, and sketches out options with you.

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  4. Build it

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

Questions about two-storey side extensions in Cranleigh

Which postcodes do you cover around Cranleigh?

We cover Cranleigh (GU6) and nearby places including Godalming, Guildford and Horsham, plus the rest of Surrey. The first site visit is free.

How much does a two-storey side extension cost in Cranleigh?

Our guide for South East England, which covers Cranleigh, is £2,260–£3,030 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £94,500–£127,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

How long does a two-storey side 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.

Do I need planning permission for a two-storey side extension in Cranleigh?

Cranleigh 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.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

We also cover places near Cranleigh, including:

Other extensions in Cranleigh

All two-storey extension services in Cranleigh · Two-storey side extensions across Surrey

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.

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