West Glamorgan · Extensions & Renovations

Double-storey extensions in Clydach

Covering SA6 and SA7 and the rest of Clydach. Guide price £55,000–£110,000 inc VAT, confirmed after a free survey.

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.

Clydach sits within our coverage for a double-storey extension, as do neighbouring Neath, Swansea and Briton Ferry. Before giving a price we want to see the property: the condition of what's there now, the access, and anything that might need extra work. The guide range for Wales is £55,000–£110,000 including VAT, and your written quote will spell out exactly what that covers.

Guide price
£55,000–£110,000 inc VAT
Time on site
14–22 weeks on site
Postcodes
SA6 and SA7
Planning rules
Wales
Local area
Swansea
Survey
Free, with a written quote

How much does a double-storey extension cost in Clydach?

The costs listed here are typical for a double-storey extension around Clydach and include VAT. They reflect labour and material costs in Wales, about 8% below the national guide, giving a range of £55,000–£110,000. Exact pricing depends on your home, so we only fix it once a free site survey is done.

Type of jobWhat it usually involvesGuide in Clydach
Small (15–20m² total)A compact rear or side extension adding a small room on each floor.£37,000–£60,000
Typical (30–40m² total)A larger kitchen or living room below with a double bedroom or en-suite above.£55,000–£110,000
Large (50m² plus total)Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing.£92,000–£166,000

What moves the price up or down:

  • Combined floor area across both storeys
  • How the new roof joins the existing roof
  • Bathrooms, en-suites and plumbing on the upper floor
  • Scaffolding duration, access and the level of finishes

What do you get?

  • 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
  • Scaffolding for the full build, erected and inspected
  • Windows, external doors, plastering and internal doors
  • Building control inspections and completion certificate
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.

Building in Clydach

Swansea's Victorian terraces climb its hillsides, its centre was largely rebuilt after wartime bombing, and Neath and Port Talbot have industrial terraces and post-war estates. Gower villages have stone cottages, and Pennant sandstone is common in older walls. Newer estates have grown on the edges of the main towns.

Hillside terraces often need repointing, rendering, roof repairs and window replacement, and loft conversions can work well. Gower stone cottages call for lime-based repairs, and estate homes commonly take extensions and driveways.

None of this holds for every street in Clydach, which is why we look at your actual house before pricing a double-storey extension rather than assuming from its age alone.

Permissions for a double-storey extension in Clydach

For anyone in Clydach, the relevant framework is Wales's. The summary below is general, so we always contact the council about your address before putting a price in writing.

In Wales, two-storey extensions are tightly limited under permitted development, including distance to the rear boundary, so most need planning permission.

Building Regulations approval is needed in Wales, and the Party Wall etc. Act 1996 applies to work on or near shared walls.

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. Free site survey

    We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a double-storey extension so the price reflects your home.

  2. 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.

  3. Dates and permissions

    We handle the paperwork side: checking whether planning permission or building control approval is needed, submitting applications where they are, and scheduling the trades and materials around your dates.

  4. Build and hand over

    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.

Working with SK Home Improvements

Permissions checked firstWe check whether planning permission or building control approval is needed for your property, and handle applications and notices where they apply.
Tidy, protected work areasFloors, furniture and access routes are covered and protected while we work, and the site is tidied at the end of every working day.
Changes agreed in writingIf something needs to change once work is under way, we explain why and confirm the cost or saving in writing before carrying on.
One contract, several tradesJobs that need builders, plasterers, electricians and decorators come under a single contract, so you are not coordinating separate firms yourself.

Double-storey extensions in Clydach: questions

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 I stay at home during the work?

In most cases, yes. Most people can live at home throughout, and we plan the work to keep disruption down by protecting floors, agreeing working hours and keeping access routes clear. Bigger jobs affecting kitchens, bathrooms or heating may mean a short spell with reduced facilities, and we talk this through with you at 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.

How long does a double-storey extension take?

A double-storey extension typically takes 14–22 weeks on site, depending on size, roof design and weather. Foundations and ground-floor walls come first, then the first-floor joists, upper walls and roof. Once it is weathertight, electrics, plumbing, plastering and finishes follow. Allow extra time beforehand for drawings, calculations and approvals. We give you a stage-by-stage programme with your quote.

Nearby towns

Homes across SA6 and SA7 in Clydach are within our coverage, as are those in Neath, Swansea and Briton Ferry. If you are just outside these areas, ask anyway, because we work right across the UK.

Ready for a written price?

Ready to talk about a double-storey extension in Clydach? Book a free site survey and we'll send you a written, fixed-price quote for the specification you choose.

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