Frequently asked questions
Straight answers about costs, planning, timescales and how we work.
How much does a house extension cost?
Our national guide is £1,750 to £3,400 per m² for single-storey work and £1,550 to £3,000 per m² for two storeys, including VAT. A standard 4 m × 5 m single-storey extension is around £41,000 to £52,000.
Is the first site visit free?
Yes, with no obligation. Remote and island addresses are visited by arrangement, with any travel costs agreed first.
Do you do the drawings?
Yes: measured survey, planning drawings, building regulations drawings and structural calculations, priced in writing before we start.
Do I need planning permission?
Often not for a single-storey rear extension. See our planning guide; we confirm the route at the site visit.
Who is my contract with?
S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Do your prices include VAT?
Yes. Our guide prices include VAT at 20%, which applies to extensions of existing homes.
How long will it take?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Can I stay at home during the build?
Usually yes. We keep the house weather-tight and plan the opening-up stage carefully.
How do payments work?
In stages tied to work completed, set out in the written contract before work starts. We never ask for the full price up front.
Do you handle party wall notices?
We tell you which notices are needed in England and Wales and when to serve them, and we can coordinate with party wall surveyors.
Do you cover Scotland and Northern Ireland?
Yes. We follow Scottish and Northern Irish planning and building rules, including the building warrant process in Scotland.
Can you work with my architect?
Yes. We can build from your architect's drawings or take over from planning drawings and prepare the building regulations pack.
What about the kitchen?
We can fit a kitchen or coordinate with your supplier. We need the layout early so drains and services are in the right place.
Do you offer finance?
We do not offer or arrange finance. Speak to your bank or an independent financial adviser about borrowing for home improvements.
What if I just want a price for the build?
Send us your approved drawings and we will price the build in writing after a site visit.
Are the photos on your site real projects?
No. They are computer-generated images showing typical extension types. We will add photos of completed projects as they are finished.