Get a rough, honest idea of the likely build cost before you go any further. Pick your project, set the size and finish, and we'll show a typical range — clearly marked as an estimate, not a quote.
Indicative build cost — estimate only
£44,000 – £64,000
for a 20 m² single-storey extension (standard finish)
A rough guide to typical build costsin the North West — this is the contractor's price, not our design fee and not a quote. Real costs vary widely with site conditions, specification, access and finishes, and are only confirmed by a builder after a proper survey. Figures exclude VAT, professional fees, planning and building-control fees, and any structural or party-wall work.
Want Sean to sense-check this?
No need to enter anything to use the estimate. If it's useful, you can send these figures to Sean for an honest first view — just your name and one way to contact you.
Every home and site is different. Foundations, drainage, access, the level of finish and unforeseen issues all move the cost. A genuine figure only comes from a builder pricing real drawings after a survey — which is exactly what our design pack lets them do, accurately.
We're design only — we prepare the drawings your project needs so builders can price and build from them. That keeps the costing honest: you compare like-for-like quotes against one clear set of drawings. See our services.
Prefer to picture it first? Try the concept visualiser.
Send Sean your name and one way to contact you for an honest first view of the design and likely route — with no obligation. The size, a postcode or a few photos help if you have them, but aren't required to start.