Key Takeaway
The Premium Package at £2,950+VAT takes you from planning drawings all the way through contractor tendering and proposal comparison — giving you everything you need to get your extension built with confidence.
Planning a home extension is one of the most significant decisions a homeowner makes. The design has to work architecturally. Planning permission needs to be secured. Building regulations must be satisfied. And ultimately, a builder has to be found, appointed, and managed through the construction phase.
Most extension design services stop at drawings. Hampshire Build's Premium Package goes further — covering the full journey from initial design concept through to a signed building contract with a vetted contractor. At a fixed fee of £2,950+VAT, it's the most complete off-the-shelf extension design service available in Hampshire.
What the Premium Package Includes
The Premium Package builds on everything in the Pre-Build Package — planning drawings, building regulations drawings, and certified structural calculations — and adds the contractor management layer that determines whether a well-designed extension actually gets built well.
Planning Drawings & Application
We begin with a full on-site measured survey, typically completed within 10 working days of receiving your deposit. From there, our qualified architectural technicians produce planning drawings to a standard that consistently achieves permission first time — Hampshire Build has a 98% planning approval rate across all submitted applications.
The planning application itself is prepared and submitted on your behalf. We handle all communication with the local planning authority and manage any information requests during the determination period.
Building Regulations Drawings
Planning permission authorises what can be built. Building regulations govern how it must be built — structural integrity, thermal performance, fire safety, drainage, and more. Both sets of drawings are included in the Premium Package, giving your contractor a complete, fully compliant technical package to build from.
Certified structural calculations are included as standard. These are prepared to the specification required by your local authority building control department and are necessary for any extension involving steelwork, altered load paths, or new roof structures.
Contractor Tender to 2 Vetted Firms
This is the element that makes Premium Package genuinely different from a standard design-only service.
Hampshire Build maintains a vetted contractor panel — builders who have been reference-checked through previous clients, price-tested on live Hampshire projects, and approved by us before any introduction to a client. When your drawings are complete, we prepare a detailed schedule of works and send it to two suitable contractors from our panel.
The schedule of works is specific to your project — not a generic document, but a line-by-line breakdown of every element of the build. Both contractors price against exactly the same document, which means the proposals that come back are genuinely comparable. No hidden variations, no scope differences that make comparison impossible.
Proposal Comparison Report
Once both contractor proposals are received, we produce a written comparison report — breaking down the two submissions line by line, identifying any differences in specification, programme, and payment terms, and providing our professional assessment of each.
This report gives you something most homeowners never have: a genuine, informed basis for choosing a contractor. Not gut feeling. Not the recommendation of a friend of a friend. An objective, evidence-based analysis of two competitive proposals prepared against the same specification.
Client Contract Template
The final component is a client contract template — a building contract structured around milestone-based payments in arrears. This protects you financially throughout construction. You pay for completed, inspected work — never in advance. If the contractor's performance falls short at any stage, you are not financially overexposed.
Who the Premium Package Is For
The Premium Package is designed for homeowners who want a genuinely complete service — not a set of drawings they then have to take to market themselves without any professional support on the contractor side.
It suits projects where getting the contractor right is as important as getting the design right. Kitchen extensions, rear single-storey extensions, side-return conversions, two-storey additions — projects in the £80,000–£200,000 build cost range where the contractor decision has real financial consequences.
It also suits homeowners who are time-poor. Managing a contractor tender process from scratch — writing a schedule of works, identifying and approaching suitable builders, comparing proposals that aren't structured consistently — is a significant time commitment. The Premium Package removes that burden entirely.
Premium Package vs Pre-Build Package: Which Is Right for You?
The Pre-Build Package (£1,950+VAT) covers planning drawings, building regulations, and structural calculations — everything needed to apply for planning permission and hand a compliant set of drawings to a contractor of your choice. If you already have a trusted builder, or you're confident sourcing and managing the contractor process yourself, Pre-Build Package is a complete, excellent-value package.
Premium Package is the right choice if you don't have an existing contractor relationship, if you want competitive pricing confirmed before committing, or if you want the reassurance of a vetted panel rather than taking a risk on an unknown firm.
The price difference is £1,000+VAT. For a build that costs £120,000 or more, the value of a structured competitive tender — and the potential to save or protect tens of thousands of pounds on contractor pricing — makes that difference straightforward to justify.
Fixed Fee: No Surprises, No Hourly Billing
Hampshire Build operates on a fixed-fee model across all packages. The £2,950+VAT Premium Package fee covers every element listed above — there are no additional charges for planning application fees (paid directly to the council by you), revisions within the agreed scope, or our time managing contractor communications during the tender process.
This is deliberate. Extension design services that bill by the hour create a misalignment between designer and client — every query, every revision, every phone call generates an additional charge. Fixed fees mean our incentive and your incentive are the same: get it right first time, efficiently, and to the standard required.
How to Get Started
The starting point for any Hampshire Build project is a complimentary design consultation — a 30-minute call with our team to discuss your project, assess feasibility, and advise on the most appropriate package for your circumstances. There is no obligation and no cost.
You can book a consultation at hampshirebuild.co.uk/feasibility-assessment, call us directly on 01722 548911, or view full package details here.
We serve homeowners across Hampshire, Surrey, Berkshire, Oxfordshire, Buckinghamshire, Hertfordshire, West Sussex, and Wiltshire. If you're within our coverage area and thinking about an extension in 2025 or 2026, we'd be glad to talk through what's possible.
