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.
In Market Harborough, as anywhere in Northamptonshire, the price of a double-storey extension is driven mainly by size, materials and access. Across the East Midlands our guide sits at £58,000–£115,000 with VAT, but restricted parking, a narrow side passage or extra preparation can move the figure either way. That is why every price we give follows a visit to the house.
- Guide price
- £58,000–£115,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- LE16
- Planning rules
- England
- Local area
- Northamptonshire
- Survey
- Free, with a written quote
Double-storey extensions prices in Market Harborough
These are guide costs, not quotes. For a double-storey extension in Market Harborough the range is £58,000–£115,000, VAT included, reflecting prices in the East Midlands that are about 4% below the national guide. Once we have visited for a free survey, you get a firm figure for the scope you approve.
| Type of job | What it usually involves | Guide in Market Harborough |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £38,500–£62,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £58,000–£115,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £96,000–£173,000 |
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 Market Harborough?
- 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
- Building control inspections and completion certificate
Local housing and a double-storey extension
Orange-brown ironstone is the signature material of many Northamptonshire villages, with limestone and Collyweston stone-slate roofs in the north-east. Northampton has Victorian terraces from its shoemaking era, Corby expanded as a post-war steel town, and Wellingborough, Kettering and Daventry have interwar, post-war and recent estates.
Ironstone cottages often need lime repairs and careful repointing. Terraces suit loft conversions and kitchen extensions, while estate homes commonly take garage conversions, porches and driveways.
With that background in mind, here is how we typically handle a double-storey extension for homes in Market Harborough, from the first visit to the finished result.
Do you need permission in Market Harborough?
Each UK nation sets its own consent rules, and Market Harborough is in England. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
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.
The four stages
Free site survey
First, someone visits your home in Market Harborough to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Quote in writing
After the survey we send a quote for a double-storey extension that fixes the price for the scope we've agreed. If you want to change materials or scope, we revise it in writing before anything is booked.
Dates and permissions
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your Market Harborough property.
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.
Why homeowners choose us
Double-storey extensions in Market Harborough: questions
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 much will a double-storey extension cost in Market Harborough?
As a guide, expect to pay £58,000–£115,000 including VAT for a double-storey extension in Market Harborough. That range is adjusted for the East Midlands, which runs about 4% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
How much does a double-storey extension cost?
A typical double-storey extension of 30–40m² across both floors costs £58,000–£115,000, built to a plastered finish. As a rough guide, allow around £1,400–£2,600 per square metre plus fixed costs for groundworks, scaffolding and fees. The second storey usually costs less per square metre than the first, because foundations and roof are shared. Bathrooms upstairs and a complex roof add most. We confirm a fixed price after the survey.
Who do I deal with during the job?
One point of contact manages your project from survey to handover. They schedule the trades working under our contract, keep you updated on progress, and are the person to call with any question. You don't need to coordinate builders, electricians or decorators separately, because that is part of what we do.
Can the new upstairs room have its own bathroom?
A new upstairs room can usually have an en-suite, provided waste pipes can reach the soil stack or a new one can be installed. Running the waste pipe to the right falls is the main design question, and a pumped system is an option where gravity will not work. We plan bathroom positions at the design stage so pipes, ventilation and insulation are built in rather than added later.
Nearby towns
Live in Market Harborough? Our coverage takes in the LE16 postcode areas and reaches out to Corby, Kettering and Wigston, so homes on the outskirts and in the next town along are included.