An extension has to join a new building to a house that still needs to drain, breathe, stay weather-tight and carry its existing services. Sweet Homes builds the agreed extension as contractor, working from drawings, structural information and approvals supplied through the professionals you appoint.
Floor area is easy to see on a drawing. The awkward work often sits at the junction: an existing drain below the proposed footprint, the route for heating and electrics, ventilation that still needs a path, or the point where the household loses use of part of the house.
We want those conditions visible before the quotation is treated as a construction price. A rough sketch is useful for the first conversation, but it leaves too much unresolved for foundations, structure, openings and services.
Your architect owns the design. Your structural engineer supplies the structural information. You appoint the building-warrant route and any planning or listed-building advice needed for the property. We read that information as the contractor and price the work it describes.
Sweet Homes can then coordinate the construction work in one written scope: site setup and protection, groundworks, drainage, structure, walls and roof, windows and external doors, internal services, plastering, flooring, decoration and fitted joinery where included. Electrical and gas work is carried out and certified through the competent trades we appoint.
We won’t fold an architect, engineer or warrant appointment into our role simply because their drawings are needed on site.
The ranges already published for Edinburgh extensions are shown below as indicative 2026 homeowner totals including VAT at the current 20% standard rate; the underlying plus-VAT bands are retained in brackets. They are not fixed prices. The Edinburgh house extension cost guide sets out what moves a figure within these ranges, scope by scope. The property, approved information and selected specification still control the quotation.
| Typical scope | Homeowner total, including VAT (underlying band plus VAT) |
|---|---|
| Side return extension, around 5–15 m² | £30,000–£54,000 including VAT (£25,000–£45,000 plus VAT) |
| Single-storey rear extension, around 15–25 m² | £42,000–£78,000 including VAT (£35,000–£65,000 plus VAT) |
| Kitchen extension with the kitchen work included | £54,000–£96,000 including VAT (£45,000–£80,000 plus VAT) |
| Two-storey rear or side extension, around 30–50 m² | £66,000–£120,000 including VAT (£55,000–£100,000 plus VAT) |
| Wrap-around extension, around 20–40 m² | £72,000–£132,000 including VAT (£60,000–£110,000 plus VAT) |
Ground conditions, drainage, glazing, roof geometry, structural design, service upgrades and the opening into the existing house can move a project outside a band. Recent-job outturn checks are required before we publish a narrower or newer range.
Late selections can also change more than the item being selected. A different door opening, kitchen position or heating decision may reach several trades. Where excavation or opening-up changes the known scope, the affected work pauses while the evidence and construction options are recorded. The specific contract sets the variation and approval process.
Many households stay while the new shell is separate from the existing rooms. Project size isn’t the useful threshold. Essential services are.
The difficult stretch may arrive when the opening is formed, or when rewiring, extensive plumbing or heating work affects the occupied rooms. We discuss that before site work and may recommend timing a holiday over it. Temporary services, clean and dirty zones, and any promise about daily availability belong in the particular contract.
Ask about the extension and the house
Extending is one way to find space and not always the cheapest. Loft conversions build into the roof and garage conversions reuse a structure that already exists, both usually with less groundwork than a new footprint. Where the property is listed, listed building renovation covers the consent route an extension there has to clear first.
How much does an extension cost in Edinburgh?
The bands published above run from £30,000 including VAT (£25,000 plus VAT) for a side return of roughly 5 to 15 square metres to £72,000 and beyond for a wrap-around. Ground conditions, drainage, glazing, roof geometry, structural design, service upgrades and the opening into the existing house can move a project outside a band.
Do I need planning permission and a building warrant?
An extension raises both questions, and they are answered separately. You appoint the building-warrant route and any planning or listed-building advice the property needs, and the appointed professional establishes which applications apply. Sweet Homes reads the approved information as the contractor and prices the work it describes.
Is a sketch enough to get a price?
It is useful for the first conversation, but it leaves too much unresolved for foundations, structure, openings and services. The awkward work usually sits at the junction with the existing house: a drain below the proposed footprint, the route for heating and electrics, ventilation that still needs a path. We want those conditions visible before a quotation is treated as a construction price.
Can we stay in the house while it is built?
Many households stay while the new shell is separate from the existing rooms. Project size is not the useful threshold; essential services are. The difficult stretch usually arrives when the opening is formed, or when rewiring, plumbing or heating work reaches the occupied rooms. We discuss that before site work starts.
How soon can the work start?
We do not book works within four weeks of a first enquiry. That period covers the call, the survey, the written quotation, your decision and the ordering that has to happen before trades arrive. If something needs attention sooner than that, say so on the call and we will point you to the right emergency trade for the immediate problem while the planned work is scheduled properly.
What happens after we enquire?
We reply by email. If the project looks like a fit we ask for the property details, any drawings or approval information and a few photographs, then arrange a twenty-minute call to work through the brief. A site visit follows the call, and the written quotation follows the visit. Send a couple of windows that suit for the call and we will hold the time.
Send the property details and what you would like the extension to do. Our team replies by email and arranges a short call to cover the brief, the warrant and any planning questions before a site visit is booked.
Our team reviews every enquiry. We use your details to reply and handle the service you request. Privacy notice.
Project responsibility
Brunon oversees project programmes across Edinburgh and is typically available by phone or email. The staff assigned to your job handle the day-to-day site work independently within the agreed scope, with the responsible contact confirmed before work starts.
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