Construction Company in Portsmouth.

Design N Build serves Portsmouth and locations within roughly 29 miles, covering residential extensions, commercial fit-out, civils and full design-build. Accredited (CHAS, Constructionline), fully insured and locally mobilised — a Portsmouth site survey is booked within 48 hours of your enquiry.

In Portsmouth we deliver extensions, loft conversions, full renovations, new-build homes, commercial fit-out, civil engineering, groundworks, drainage and turnkey design-build. Every Portsmouth project is single-contract, fixed price and managed by a dedicated project manager from brief to handover.

Survey within 48 hours, fixed-price BOQ in 7–10 days, and Portsmouth site mobilisation usually 2–3 weeks after contract sign-off. Emergency or urgent commercial works can be brought forward where programme allows.

Yes. We hold £5M public liability cover, employer's liability insurance, professional indemnity, plus CHAS, Constructionline and SafeContractor accreditation — the standards required to deliver public-sector and commercial work across Portsmouth.

Costs in Portsmouth vary by scope: rear extensions £1,800–£2,800 per m², loft conversions £45,000–£75,000, commercial fit-out £600–£1,500 per m². You'll receive a fixed-price Portsmouth BOQ — never a vague estimate — after the free site visit.

Yes. We run pre-application advice, full planning submissions, Building Regulations applications and condition discharge with the local authority covering Portsmouth, plus party wall, CDM and statutory undertaker liaison. One team handles every approval.