Cambridgeshire · Extensions & Renovations

Double-storey extensions in St Neots

Guide price £63,000–£126,000 including VAT, typically 14–22 weeks on site, with a free site survey and a written fixed price.

Two-storey side extension on a brick semi-detached house

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A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.

If you have a double-storey extension on your list for a property in St Neots, we can help from the first measurements to the final clean-up. For a typical home, plan for 14–22 weeks on site, though larger or more complex jobs take longer. We cover postcodes PE19 and nearby Huntingdon, Bedford and Kempston, and every quote we send is fixed for the scope described in it.

Guide price
£63,000–£126,000 inc VAT
Time on site
14–22 weeks on site
Postcodes
PE19
Planning rules
England
Local area
Cambridgeshire
Survey
Free, with a written quote

How much does a double-storey extension cost in St Neots?

In St Neots, guide figures for a double-storey extension sit at £63,000–£126,000, VAT included. We set them using rates for the East of England, currently about 5% above the national guide. The table shows what pushes a project towards either end of the range; your own price is set after a free survey.

Type of jobWhat it usually involvesGuide in St Neots
Small (15–20m² total)A compact rear or side extension adding a small room on each floor.£42,000–£68,000
Typical (30–40m² total)A larger kitchen or living room below with a double bedroom or en-suite above.£63,000–£126,000
Large (50m² plus total)Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing.£105,000–£189,000

Your price depends mostly on:

  • Combined floor area across both storeys
  • Bathrooms, en-suites and plumbing on the upper floor
  • Foundation depth, ground conditions and drains to divert
  • Scaffolding duration, access and the level of finishes

What does the job include in St Neots?

  • Groundworks, foundations and below-ground drainage
  • Insulated cavity walls with brick or render to match the house
  • First-floor joists, stud walls and new openings upstairs
  • Roof structure tied into the existing roof, tiled to match
  • Scaffolding for the full build, erected and inspected
  • Windows, external doors, plastering and internal doors
Rear two-storey extensionAdds depth at the back, often a kitchen-diner below and a bedroom above.
Over-garage extensionBuilds a new room above an existing garage, checking the foundations first.
Hipped roofA roof that slopes on every side, matching many semi-detached and detached homes.
Gable roofA simpler pitched roof with a triangular end wall, usually quicker to build.

What are homes like around St Neots?

Cambridge has many Victorian terraces in pale gault brick, with Edwardian villas and modern estates around the city. Peterborough expanded as a new town from the 1970s, adding large planned estates, while Ely, Huntingdon, St Neots and the Fenland market towns keep Georgian and Victorian centres. Limestone appears in villages near the Northamptonshire border.

Narrow terraces commonly suit loft conversions and kitchen extensions. Newer estate homes often need garage conversions, porches and landscaping, and older brick and stone buildings may call for lime-based repointing and carefully specified windows.

Knowing the typical building types in Cambridgeshire helps, but a survey of your own home in St Neots is what decides the right approach to a double-storey extension.

Do you need permission in St Neots?

As St Neots is in England, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.

In England, a two-storey rear extension can only be permitted development if it is no more than 3 m deep, at least 7 m from the rear boundary and finished to match the house. Most double-storey and all two-storey side extensions need full planning permission.

Building Regulations approval is needed, with structural calculations for beams, foundations and the roof. The Party Wall etc. Act 1996 often applies on semi-detached and terraced houses.

Rules change and every property is different, so we check the planning history and constraints for your address before we quote.

How does the job run?

  1. We look at the job

    It starts with a survey at the property, free of charge. We check condition, access and services, ask how you want the finished result to look, and answer any questions you have about a double-storey extension.

  2. Price and scope agreed

    Next you receive a written quote with a fixed price for the agreed specification. It lists what is included, what is not, and how payments are staged, so you can compare it properly.

  3. Booking the work

    Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a double-storey extension are in place before the first day on site.

  4. Finish and handover

    The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.

How we work

One point of contactA single named contact handles your project from the first survey to the final handover, so you always know who to call with a question.
Written, fixed-price quotesYour quote states one fixed price for the work as we have specified it together, with inclusions and exclusions listed so there are no grey areas.
Permissions checked firstWe check whether planning permission or building control approval is needed for your property, and handle applications and notices where they apply.
Certified where requiredElectrical, gas and other notifiable work is carried out by suitably registered people, and you receive the relevant certificates when it is finished.

Questions about a double-storey extension in St Neots

Is a double-storey extension better value than single-storey?

A double-storey extension usually gives better value per square metre than a single-storey one, because the same foundations and roof serve twice the floor area. The overall cost is higher, and planning can be harder because of the effect on neighbours. If you might want an extra bedroom later, building both floors now avoids a second round of disruption and scaffolding.

How is the new roof joined to the existing house?

The new roof is usually tied into the existing roof so the two read as one. On a rear extension this often means a lower ridge or a hipped end, with valleys where the slopes meet. We strip back some existing tiles, fix new rafters and battens, and lay matching tiles or slates. Lead or proprietary flashings seal the junctions so water runs off properly.

How long will a double-storey extension take?

On a typical home, allow 14–22 weeks on site. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.

Is the price fixed?

Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.

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

Most two-storey extensions need planning permission, but it depends on the size, height and position, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, a two-storey rear extension can sometimes be built under permitted development if it is no deeper than 3m and at least 7m from the rear boundary. We check what applies before quoting.

Near St Neots

Live in St Neots? Our coverage takes in the PE19 postcode areas and reaches out to Huntingdon, Bedford and Kempston, so homes on the outskirts and in the next town along are included.

Ready for a written price?

Tell us a little about your home in St Neots and what you have in mind for a double-storey extension. We'll arrange a site survey, free of charge, and put our price in writing.

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