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.
Getting a double-storey extension right in Peacehaven starts with understanding the house you already have: its age, how it was built and what has been altered over the years. We survey first, then commit on paper to a price that holds as long as the scope stays the same. Across the South East, guide prices run at £67,000–£134,000 including VAT, and homes in Rottingdean, Seaford and Brighton are covered too.
- Guide price
- £67,000–£134,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- BN10
- Planning rules
- England
- Local area
- East Sussex
- Survey
- Free, with a written quote
How much does a double-storey extension cost in Peacehaven?
Budgeting for a double-storey extension in Peacehaven? The numbers below include VAT and are adjusted for the South East, where costs are about 12% above the national guide. The headline range is £67,000–£134,000. Nothing is final until we have measured up at a free survey and agreed the specification with you.
| Type of job | What it usually involves | Guide in Peacehaven |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £45,000–£73,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £67,000–£134,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £112,000–£202,000 |
Your price depends mostly on:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Foundation depth, ground conditions and drains to divert
- Scaffolding duration, access and the level of finishes
What does the job include in Peacehaven?
- 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
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
What are homes like around Peacehaven?
Brighton and Hove are known for Regency stucco terraces and bow-fronted houses, alongside Victorian terraces climbing the hills. Lewes and Brighton have mathematical tiles and flint walls, Eastbourne has large Victorian and Edwardian villas, and Wealden villages use tile-hanging, weatherboarding and timber frames. Interwar suburbs and newer estates fill out most towns.
Seafront homes face salt-laden south-westerly winds and driving rain, while Wealden clay can shrink and swell, affecting extension foundations.
For a double-storey extension in Peacehaven, this means checking things like wall construction, roof structure and existing services before we put a figure on paper.
Planning and building rules in Peacehaven
England, Wales, Scotland and Northern Ireland each handle planning a little differently. Peacehaven comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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.
From survey to handover
A visit to your home
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a double-storey extension, and photograph or measure anything the quote needs to reflect.
Your fixed price
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
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
On site to finish
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
Why homeowners choose us
Common questions
Do you cover Rottingdean, Seaford and Brighton?
Yes. As well as Peacehaven, we cover Rottingdean, Seaford and Brighton and the rest of East Sussex. Our coverage is UK-wide, so the process is the same wherever you are: a free site survey, a quote in writing that fixes the price for the agreed scope, and one point of contact while the work is planned and carried out.
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
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.
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.
How much will a double-storey extension cost in Peacehaven?
As a guide, expect to pay £67,000–£134,000 including VAT for a double-storey extension in Peacehaven. That range is adjusted for the South East, which runs about 12% above 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.
Nearby towns
Homes across BN10 in Peacehaven are within our coverage, as are those in Rottingdean, Seaford and Brighton. If you are just outside these areas, ask anyway, because we work right across the UK.