How to Choose a Builder

The builder you appoint will have more influence on whether your project succeeds than almost any other decision you make. A well-designed scheme can be undone by poor workmanship, a poorly managed programme, or a contractor who doesn't communicate. We've seen it happen. Here's what we look for when helping clients find the right person for the job.

Our Director, Imran Jahn, on the BBC during a site visit with client during construction

Start with the Basics

Before anything else, verify that the builder is a properly constituted business. Are they a registered company? Do they have current public liability insurance, employers' liability insurance, and contractors' all-risk cover? Ask to see the documents rather than taking their word for it. A reputable builder will hand these over without hesitation.

Check their company history. How long have they been trading under their current name? Have they dissolved previous companies? A straightforward Companies House search takes five minutes and can tell you a great deal. You're not being suspicious. You're doing reasonable due diligence on someone you're about to hand a significant sum of money to.

Ask about guarantees. Will they provide a written guarantee on their work, and is it backed by insurance? A builder who is confident in the quality of what they do won't object to this. One who hedges or deflects is worth noting.

Look Beyond the Quote

Getting a quote is the easy part. Understanding what it actually covers is where clients often find themselves in difficulty later.

A proper quote should be detailed, tied to a specific set of drawings and a specification, inclusive of VAT, and clear about what's included and what isn't. Provisional sums, items where the cost hasn't been pinned down, should be identified explicitly rather than buried in a contingency figure. A quote that's suspiciously low often means that items have been excluded or underpriced, and the real cost emerges through variations once the project is underway.

Ask for the quote to be broken down by trade or work package. This makes it possible to compare quotes from different contractors on a like-for-like basis, and it gives your architect something meaningful to review.

Ask about the programme. How long do they expect the work to take? What are the key milestones? Are there any known constraints, material lead times, specialist subcontractor availability, that could affect the timeline? A builder who has thought carefully about the programme before tendering is a different proposition from one who gives you a rough duration and figures they'll work it out as they go.

Who Is Actually on Site?

This is a question more clients should ask and fewer do. The person who comes to meet you and price the job is often not the person who runs the site day to day. The site manager is the person who matters most to the daily reality of your project: they coordinate the trades, they communicate with your architect, they make the hundreds of small decisions that collectively determine whether the build goes well or badly.

Ask who would be managing the site. What's their background? Have they run projects of this type and scale before? Can you meet them before you make your decision? A builder who can't or won't answer these questions clearly is one to be cautious about.

Ask about the subcontractors they use for specialist trades: plumbers, electricians, groundworkers. Do they have established relationships with people they trust, or are they pulling in whoever's available? The quality of the supporting trades is as important as the main contractor's own work.

References and Previous Work

Every builder will tell you their past projects went well. The useful information comes from speaking to the people they worked with.

Ask for references from both previous clients and from the architects who ran those projects. The questions worth asking a previous client are: did the builder show up when they said they would, did the project finish close to the agreed programme, were variations handled transparently, and would they use them again without hesitation? The questions worth asking a previous architect are: did the builder work to the drawings, did they flag problems early or try to paper over them, and did they manage the site professionally?

If possible, visit a completed project. Photos are curated. Standing in a finished room and looking at the quality of the joinery, the junctions between materials, the finish on the plastering, tells you considerably more.

Online reviews are useful as a cross-reference but shouldn't carry too much weight on their own. A builder with fifty four-star reviews may have a very different track record on complex residential projects than on straightforward decorating work.

The Contract

Any builder who is reluctant to work under a formal contract is one to walk away from. The contract is not a sign of distrust. It's the framework that protects both parties if something goes wrong, and on any project of meaningful scale, something always requires a decision that wasn't anticipated at the outset.

We recommend JCT contracts for our residential projects. The JCT Intermediate Contract or the JCT Minor Works Contract, depending on the project's scale and complexity, provides a clear structure for payment, variations, delays, and dispute resolution. The contract should be tied to the drawings and specification, and both parties should understand what they're signing.

Payment terms should be clear. We typically recommend stage payments certified by the architect rather than upfront lump sums or payment structures that front-load money to the contractor before the work is done. Retention, a percentage of each payment held back until practical completion and then released after a defects liability period, is standard practice and reasonable to insist on.

The Architect's Role During Construction

Appointing an architect for contract administration during the build is something we always recommend to our clients, and it's worth explaining why.

The architect's role during construction isn't just to check that the building looks right. It includes reviewing the contractor's programme and progress, inspecting the work at key stages against the drawings and specification, certifying payment applications after verifying that the work they cover has been properly completed, managing variations, and maintaining a contemporaneous record of instructions and decisions.

This sustained professional involvement protects the client in ways that are difficult to replicate without it. A payment certified by an architect carries a level of scrutiny that a client acting alone typically can't provide. Problems caught at inspection stage are dealt with before they're concealed by subsequent work. Variations are documented and priced transparently rather than appearing as surprises in a final account.

At RISE we conduct weekly site visits during active construction phases. We maintain site inspection reports and a running instruction log. We review the contractor's programme and flag concerns about progress early. We're not on site to manage the build on the contractor's behalf; that's their job. We're there to protect the client's interests and make sure that what was designed is what gets built.

A Checklist Worth Using

Before recommending a builder to a client, we run through a consistent set of questions. Here's the version you can use yourself:

Are they a registered company with verifiable trading history? Do they carry current public liability, employers' liability, and contractors' all-risk insurance? Is their quote detailed, VAT-inclusive, and tied to a specific set of drawings? Do they have a clear and realistic programme? Can they tell you who will manage the site and what their background is? Do they work under formal JCT or equivalent contracts? Can they provide references from both clients and architects on comparable projects? Do they have relevant experience in projects of similar type, scale, and construction complexity? Are they willing to work with an architect as contract administrator? Do they provide written guarantees on their work?

If the answer to all of those is yes, you're in a strong position. If there are gaps, it's worth understanding why before you commit.

Taking Your Time

The pressure to appoint quickly, particularly when a project has planning permission and the client is keen to get started, can lead to decisions that create problems for months afterwards. A good builder on a well-run project is considerably less stressful than a poor choice discovered after the contract is signed.

At RISE we run a formal tender process for our projects: a consistent package of drawings and specifications sent to a shortlist of contractors, returned by a deadline, reviewed comparatively, and followed up with clarification meetings before a recommendation is made. That process takes time. It's time well spent.

If you'd like help thinking through the builder selection process for your project, we're glad to talk it through.

→ Email us at architects@risedesignstudio.co.uk
→ Or call the studio on 020 3947 5886

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