Introduction
When it comes to home renovations or building projects, one of the most important steps you can take is putting everything in writing—starting with your builder contract. This document acts as a legal agreement between you and your contractor, laying out the scope of work, timeline, payment schedule, and much more.
Without a clearly defined contract, misunderstandings can quickly escalate into disputes, cost overruns, or unfinished work. Unfortunately, too many homeowners skip this crucial step or sign vague agreements that offer little protection. That’s why understanding what to include in your builder contract before signing anything is essential.
This guide walks you through every detail you should have covered in your agreement, ensuring your project stays on track—and your investment is protected.
Why Builder Contracts Matter
Builder contracts are more than just paperwork—they’re the foundation of a successful building project. A well-written contract protects both the homeowner and the builder by clearly outlining responsibilities, expectations, and legal obligations.
Without a detailed contract in place, even minor misunderstandings can snowball into serious disputes. According to consumer watchdogs in the UK, building work is one of the top causes of complaints among homeowners, often due to unclear agreements or unmet expectations.
A proper contract helps to:
- Define the exact scope of the project and avoid scope creep
- Set agreed-upon timelines for key stages and completion
- Clarify payment schedules and acceptable methods
- Provide legal recourse in case of breaches or disputes
Whether you're renovating a kitchen or building a new extension, a contract ensures that everyone is on the same page from day one—minimising risks and maximising peace of mind.
Key Elements to Include in a Builder Contract
A strong builder contract should leave no room for ambiguity. Every project is unique, but the essential elements of a good agreement remain the same. From timelines to payments, each clause should clearly define what’s expected of both parties. This section breaks down the must-have components that protect your home, budget, and peace of mind.
Full Contact Information
Your builder contract should begin with the full legal names and up-to-date contact details of all parties involved. This includes the homeowner, the builder or company name, registered business address, email, and phone number.
This information is critical for identification and ensures accountability. In case of legal disputes, having accurate details makes it much easier to enforce terms or pursue claims.
Don’t forget to verify the builder's business registration and company number where applicable. You can cross-check this with Companies House or by reading our guide on how to check a trade is trustworthy.
Detailed Scope of Work
Arguably one of the most important parts of your builder contract, the scope of work defines exactly what your builder is responsible for—and what they’re not. A vague or overly broad description can lead to disputes, delays, or unexpected costs down the line.
Your contract should include a detailed, itemised breakdown of the work to be carried out. This should cover:
- Work specifics: Each task or phase of the project should be clearly listed (e.g., demolition, groundwork, roofing, plastering, electrical, plumbing, finishes).
- Materials to be used: Specify brands, types, and grades of materials. For example, if your bathroom tiling should be porcelain, state that clearly to avoid cheaper substitutes.
- Inclusions and exclusions: State what’s included (e.g., site clearance) and what isn’t (e.g., interior decoration or landscaping).
- Design drawings or plans: Attach architectural drawings, sketches, or specifications that the builder is expected to follow.
Providing this level of detail ensures both parties are on the same page, helping avoid what’s often referred to as “scope creep”—where additional tasks are added informally, causing time and cost overruns.
If you're unsure about how much detail to include, it's worth discussing with your contractor upfront. You can also refer to our guide on how to choose and communicate with your contractor for tips on setting clear expectations from the start.
Project Timeline & Milestones
Every builder contract should include a clear and realistic timeline for the project. This goes beyond just the start and finish dates—your agreement should outline key milestones and deadlines throughout the job. Doing so helps track progress, hold your contractor accountable, and avoid unnecessary delays.
Your timeline section should include:
- Project start date: Confirm when work will officially begin on site.
- Estimated completion date: Define when the project is expected to be fully completed, including any snagging or finishing work.
- Milestones: Break the project into stages with target completion dates (e.g., foundations completed by Week 3, first fix electrics by Week 6).
- Dependencies: Note any elements that rely on third parties or materials (e.g., delivery of custom kitchen units).
- Consequences of delay: Specify what happens if deadlines aren’t met—will there be financial penalties or revised delivery expectations?
Establishing milestone dates also makes it easier to link them with your builder payment schedule, ensuring that payments are only made when agreed stages are completed to your satisfaction.
While some flexibility is necessary—especially for weather-dependent work—setting expectations from the outset will significantly reduce the risk of disputes and project overruns.
Payment Schedule & Method
Agreeing on a clear, fair, and secure payment schedule is one of the most critical parts of any builder contract. It ensures your builder is compensated appropriately while giving you the assurance that payments are tied to measurable progress on the project.
Your payment terms should include:
- Total project cost: Clearly state the full agreed price, including VAT if applicable. Avoid vague estimates unless explicitly labelled as provisional.
- Staged payments: Break the total into milestone-based payments (e.g., deposit, post-foundation, post-roof, final snagging). Each payment should align with specific deliverables.
- Deposit terms: Many builders ask for a deposit of 10–20% to secure materials and confirm the job. Ensure this is reasonable and receipted.
- Final payment: Hold a portion (often 5–10%) until the project is fully completed and snagging is resolved.
- Accepted payment methods: Specify how payments should be made—bank transfer, card, or through a secure platform.
To protect your money and keep the project running smoothly, we strongly recommend using SafePay, our secure payment platform. SafePay ensures funds are only released to the builder once the agreed stage of work is complete and approved by you—offering peace of mind to both parties.
Never pay in full upfront or in cash without a receipt. A structured payment plan tied to project progress keeps everyone accountable and reduces financial risk.
Insurance & Warranties
Before signing any builder contract, it’s vital to confirm that the contractor has the appropriate insurance and is offering relevant warranties. These safeguards protect both your property and your finances if anything goes wrong during—or after—the build.
Your contract should outline the following insurance details:
- Public liability insurance: This covers damage to your property or injuries caused by the builder or their workers. Verify coverage amounts are sufficient for the scale of your project.
- Employer’s liability insurance: If your builder has employees or subcontractors, this is legally required to cover injuries sustained on the job.
- Contract works insurance: Optional, but valuable—this protects the building work itself against theft, vandalism, or accidental damage before handover.
Ask for proof of these policies before work begins. Legitimate tradespeople will be happy to provide insurance certificates and policy details.
On top of that, check what warranties or guarantees the builder offers once the job is complete. This should include:
- Workmanship warranty: A builder-backed guarantee for a specified period (usually 6–12 months) on their labour.
- Manufacturer warranties: On materials, appliances, or fixtures supplied—e.g., boilers, windows, or roofing tiles.
Including these terms in your contract helps you avoid lengthy disputes if problems arise after the work is finished. And if you're unsure whether a builder is reliable, you can read our full guide on how to check if a trade is trustworthy.
Dispute Resolution Clause
Even with the most detailed builder contract, disagreements can occasionally arise—whether it's over delays, cost variations, or workmanship quality. That’s why it’s smart to include a clear dispute resolution clause in your contract, outlining how issues will be handled if they occur.
This clause should provide a step-by-step process for resolving disputes before either party takes legal action. Common elements include:
- Initial resolution period: Set a timeframe (e.g., 7 days) for the builder and homeowner to attempt informal resolution through direct communication.
- Mediation: If direct discussions fail, specify that both parties agree to use a neutral third-party mediator. Mediation is faster, cheaper, and less confrontational than going to court.
- Arbitration or adjudication: For more formal disagreements, the contract can allow for binding arbitration or adjudication. This is especially relevant for larger-scale projects.
- Jurisdiction: State which legal jurisdiction (typically the UK) will govern the contract and any potential legal action.
Having this process in writing gives both parties a clear path to follow and can prevent costly legal disputes. It’s a sign of a professional agreement and promotes a cooperative working relationship.
Better still, by choosing a reputable, vetted contractor through BookaBuilderUK, you reduce the risk of disputes in the first place. Trustworthy tradespeople are more likely to follow through on their commitments and resolve issues fairly.
Change Order Procedures
No matter how well you plan a building project, changes during construction are common. You may decide to upgrade materials, adjust layouts, or add extra work. Without a formal process for handling these changes—known as “change orders”—you risk confusion, cost overruns, and timeline extensions.
Your builder contract should include a clear procedure for documenting and approving changes to the original scope of work. This should cover:
- Written authorisation: All changes must be agreed in writing before any new work begins. This could be via signed documents, email confirmations, or a formal change order form.
- Updated costs: Any additional costs (labour, materials, VAT) must be clearly outlined and approved before proceeding. Avoid vague verbal agreements.
- Timeline impact: Specify whether the change affects the completion date or other milestones—and by how much.
- Record keeping: Maintain a log of all approved changes, including dates, signatures, and itemised details. These records can be vital in the event of a dispute.
Builders should never proceed with significant changes unless authorised by you—and you shouldn’t feel pressured to agree on the spot. Take time to review the cost and implications before signing anything.
Establishing this process from the outset makes communication clearer, protects your budget, and helps the project stay on track. For more tips on keeping discussions productive, check out our guide on how to communicate effectively with your contractor.
Termination Clauses
While no one enters a building contract expecting it to end early, things don’t always go to plan. Unforeseen issues—like delays, poor workmanship, non-payment, or changing personal circumstances—can make continuing a project unfeasible for either party. That’s why your contract should include a clear termination clause.
A termination clause outlines the conditions under which the contract can be ended and what happens if that occurs. It should cover:
- Grounds for termination: Define valid reasons either party can end the contract. For example, repeated missed deadlines, lack of payment, breach of contract terms, or prolonged site inactivity.
- Notice period: Specify how much written notice must be given (e.g. 7–14 days), giving the other party time to resolve the issue or prepare for closure.
- Final payments: Clarify what happens financially if the contract ends early. This includes paying for completed work, returning unused materials, or issuing refunds for unearned deposits.
- Handover of work: State that any partially completed work or documentation (like drawings or certifications) must be handed over in the event of termination.
This clause protects both sides and provides a formal process for walking away if the relationship breaks down. It’s especially important for larger or longer-term projects where greater risks are involved.
Including this safety net in your builder contract adds transparency and can reduce the likelihood of disputes escalating into legal action. If you’re unsure how to word this clause properly, it may be worth consulting a solicitor—especially if the project is high-value or complex.
Red Flags to Watch Out For
Not all contracts are created equal—and some may contain vague terms or omissions that leave you exposed to risk. Before signing anything, it’s crucial to review your builder contract with a critical eye and watch out for warning signs that could signal potential issues.
Here are some common red flags to look out for:
- Vague or missing scope of work: If the contract doesn’t clearly outline what’s included, you're likely to face disputes over “extras” and what was actually agreed upon.
- No payment schedule: A contract that asks for large upfront payments without a clear, stage-based plan should raise concern. Reputable builders should offer structured payment terms tied to progress.
- Lack of completion dates: If your contract doesn’t mention deadlines or milestones, it becomes difficult to hold the builder accountable for delays.
- No mention of insurance: Contracts that don't include proof of insurance or warranty details could leave you financially vulnerable if things go wrong.
- Verbal agreements only: Avoid arrangements where critical details are agreed on verbally or by text message without formal documentation.
- No dispute resolution clause: Without a process in place, any disagreements may quickly escalate, leading to costly delays or even legal action.
If you're unsure about any part of the contract, don’t be afraid to ask questions or request revisions. And remember, a trustworthy tradesperson will never pressure you into signing something you don’t fully understand.
To help ensure you’re dealing with a reliable and professional builder, check out our expert guide on how to check a trade is trustworthy.
Communicating with Your Builder About the Contract
Even the most thorough contract can fall short if there’s poor communication between you and your builder. A contract should be a collaborative agreement—not a one-sided document. Open, honest dialogue is key to ensuring everyone understands their responsibilities and agrees with the terms before work begins.
Here’s how to approach contract discussions with your builder effectively:
- Start early: Talk about expectations, timelines, and budget limits before the contract is drafted. This helps avoid revisions and misunderstandings later on.
- Ask questions: If any part of the contract is unclear—especially legal or technical language—ask for clarification. A reputable builder will be happy to explain.
- Request changes if needed: Don’t be afraid to suggest edits. Whether it's altering payment terms or clarifying the scope of work, make sure you’re comfortable with every section.
- Put everything in writing: Always confirm agreements in writing. Don’t rely on verbal promises, no matter how trustworthy your builder seems.
- Agree on a single point of contact: Establish who will communicate on behalf of the builder (e.g., site manager or company owner) to avoid mixed messages.
Clear, respectful communication builds a stronger working relationship and reduces the likelihood of disputes. For a more in-depth guide to working smoothly with your tradesperson, read our blog on how to choose and communicate with your contractor.
Should You Hire a Solicitor to Review the Contract?
For many small home improvement projects, a well-drafted builder contract agreed upon by both parties may be sufficient. However, for larger or more complex works—such as extensions, loft conversions, or full renovations—it can be wise to have a legal professional review the agreement before you sign.
A solicitor experienced in construction contracts can help you:
- Spot hidden risks: They can identify clauses that are vague, biased, or missing altogether—protecting you from future legal headaches.
- Clarify your obligations: Contracts go both ways, and a solicitor can help you understand your responsibilities, including access, payments, and approvals.
- Ensure compliance: A legal review can check that the contract complies with relevant UK laws, planning permissions, and building regulations.
- Negotiate fairly: If certain terms feel unreasonable, a solicitor can suggest alternative wording or help you renegotiate from an informed position.
The cost of a solicitor is typically small compared to the overall project budget—and it could save you thousands if a dispute arises later. It’s especially advisable if:
- You’re investing a significant amount (e.g., £25,000+)
- The contract includes complex or technical terms
- You feel unsure about any part of the agreement
That said, many reputable builders will already use standardised contracts that cover all essential elements. If you’re working with a vetted professional found through BookaBuilderUK, chances are their documentation will be fair, transparent, and industry-compliant.
Final Builder Contract Checklist
Before you sign on the dotted line, run through this checklist to make sure your builder contract includes all the essential details. This quick review can save you from future headaches and ensure your project runs smoothly from start to finish.
- ✔️ Full legal names and contact details of all parties
- ✔️ A clearly defined scope of work, including inclusions and exclusions
- ✔️ Detailed materials list and agreed specifications
- ✔️ Start and completion dates, with milestone targets
- ✔️ Payment schedule tied to project milestones
- ✔️ Deposit terms and final payment conditions
- ✔️ Insurance details (public liability, employer’s liability, etc.)
- ✔️ Warranties on workmanship and materials
- ✔️ A formal change order process for handling adjustments
- ✔️ A dispute resolution clause to avoid legal conflicts
- ✔️ Termination terms outlining how either party can exit the agreement
- ✔️ Signatures from both parties with date of agreement
For added peace of mind, you may want to print this list or save it digitally as a reference during the project. And remember, if something’s missing or unclear—ask your builder to revise the contract before work begins.
Final Thoughts
A detailed builder contract isn’t just a formality—it’s your safety net. It defines expectations, secures your investment, and sets the tone for a professional, well-managed project. Whether you're tackling a kitchen renovation or a major extension, taking the time to get the paperwork right can save you time, money, and stress.
From payment terms to project timelines and dispute procedures, every detail matters. Don’t rush the contract stage or settle for a vague agreement. Be proactive, ask questions, and always ensure everything is agreed in writing before any work begins.
Looking for a reliable, vetted contractor? BookaBuilderUK connects homeowners with trusted tradespeople across the UK—so you can hire with confidence, knowing your builder is backed by genuine reviews and verified credentials.
Start your next home improvement project the right way—with a solid contract and a trustworthy builder by your side.
