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What to Check Before Signing a Building Contract
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What to Check Before Signing a Building Contract
A building contract should make the agreement between you and your builder clear before work starts.
It should explain:
- What work is being carried out
- How much it will cost
- When payments are due
- When the work should start
- How long it is expected to take
- How changes are handled
- What happens if there are delays
- Who is responsible for different parts of the project
- What happens at completion
- How disputes are dealt with
A contract does not remove every construction risk.
But a clear contract can greatly reduce misunderstandings by setting out what both sides have agreed.
At Tholos Architects, we help clients review project information and understand whether the contract reflects the drawings, quotation and agreed scope before construction begins.
Check a Builder Contract explained
Why a Building Contract Matters
A construction project can involve:
- Significant financial commitment
- Multiple trades
- Specialist materials
- Structural work
- Design information
- Long programmes
- Changes during construction
Relying only on verbal discussions can create problems later.
A written contract provides a record of the agreement.
This can become particularly important if there is disagreement over:
- Price
- Scope
- Delays
- Variations
- Payments
- Completion
- Defects
Check Who the Contract Is With
Start with the basics.
The contract should clearly identify the parties.
Check:
- Client name
- Legal business name
- Trading name
- Business address
- Company number where applicable
The contractor named in the contract should match the party named on:
- Quotation
- Invoices
- Insurance documents
Do not assume that similar trading names refer to the same legal business.
Check the Property Address
The contract should clearly identify the property where the work is taking place.
Check that the address is correct and complete.
For larger projects, it may also be useful for the contract to reference:
- Drawings
- Specifications
- Schedules
- Other project documents
Check the Scope of Work
The contract needs to make clear what the builder has agreed to construct.
The scope may refer to:
- Drawings
- Structural information
- Specification
- Schedule of works
- Builder quotation
Make sure the documents listed are the correct versions.
If the design has changed, an old drawing revision should not remain part of the contract by mistake.
Check the Drawing Revisions
Architectural and structural drawings can go through several revisions.
The contract should identify the set being used for construction.
Check:
- Drawing number
- Revision
- Date
This matters because a contractor should not later be able to say they priced or agreed a different version of the project.
Check the Builder’s Quote Is Included Properly
If the quotation forms part of the contract, make sure it is the final agreed version.
It should reflect any clarifications made during tender discussions.
For example:
- Items added
- Items removed
- Corrected allowances
- Revised prices
- Agreed exclusions
Do not rely on an old quotation if important changes were agreed afterwards.
Check a Builder Contract
Check What Is Included
The contract should align with the agreed scope.
Depending on the project, this may cover:
- Demolition
- Groundworks
- Structure
- Roofing
- Windows
- Electrical work
- Plumbing
- Heating
- Plastering
- Joinery
- Decoration
- Flooring
- External works
You should be able to understand what the builder is responsible for.
Check the Exclusions
Exclusions should be understood before signing.
Common examples can include:
- Kitchen
- Sanitaryware
- Flooring
- Decoration
- Landscaping
- Professional fees
- Building Control fees
- Party-wall costs
- Specialist items
If something important is excluded, make sure you know:
- Who is responsible for it
- When it needs to be arranged
- How it affects the programme
Check the Contract Price
The contract should clearly state the agreed price or explain how the final price will be calculated.
Check whether the price is:
- Fixed
- Estimated
- Subject to adjustment
- Based partly on allowances
Also check whether VAT is:
- Included
- Added separately
- Not applicable
Check Provisional Sums and Allowances
Some parts of the project may not have a final price when the contract is signed.
These may be included as:
- Provisional sums
- Prime cost allowances
- Estimated amounts
Make sure you understand:
- Which items are allowances
- How much has been included
- How the final cost will be adjusted
Otherwise, the headline contract value may give a misleading impression of the eventual cost.
Check the Deposit
If a deposit is required, the contract should make the amount and purpose clear.
Ask:
- How much is due?
- When is it due?
- What does it cover?
- Is it linked to materials?
- Is it refundable in any circumstances?
A deposit should not simply appear as an unexplained figure.
Check the Payment Schedule
Understand when payments become due.
Payments may be based on:
- Dates
- Construction stages
- Valuations
- Milestones
Check:
- Amount
- Timing
- What triggers payment
- How payment requests will be issued
The schedule should make sense in relation to progress.
Check Final Payment
The contract should explain when final payment is due.
This may be linked to:
- Practical completion
- Completion of snagging
- Final account
- Delivery of certificates
Make sure the trigger is clear.
Check Whether Retention Applies
Some contracts allow a small percentage of payment to be retained until:
- Practical completion
- End of a defects period
- Outstanding items are resolved
Whether this applies depends on the contract and project.
If retention is included, check:
- Percentage
- Release date
- Conditions for release
Check a Builder Contract
Check the Start Date
The contract should identify when work is expected to begin.
This may be:
- A specific date
- A period after certain conditions are met
If the start depends on something else, this should be understood.
Examples might include:
- Approval
- Access
- Materials
- Client decisions
Check the Construction Period
The contract should explain the expected duration of the work.
This could be expressed as:
- Number of weeks
- Completion date
- Agreed programme
The timeframe should be realistic for the project.
Check the Completion Date
Where a completion date is stated, check how it has been calculated.
Also understand whether it can change.
Construction contracts often allow completion dates to move where legitimate delays occur.
Check How Delays Are Handled
This is one of the most important sections.
Ask what happens if the project is delayed because of:
- Client decisions
- Late information
- Material shortages
- Weather
- Unforeseen site conditions
- Changes to the work
- Contractor delay
The contract should explain how extensions of time are dealt with.
Check Client-caused Delays
Clients can also delay construction.
For example:
- Late selections
- Late approvals
- Changes in design
- Restricted access
- Delayed payments
The contract should explain how these situations affect:
- Programme
- Cost
- Completion date
Check Builder-caused Delays
The contract should also address delays for which the contractor may be responsible.
The treatment depends on the contract being used.
What matters is that the position is clear rather than assumed.
check a builder quote
Check Building Control and Certification
Clarify which costs and responsibilities sit with the builder.
Depending on the project, this may involve:
- Building Control inspections
- Electrical certification
- Gas certification
- Window certification
- Commissioning documents
- Other specialist certificates
Professional and statutory fees may be excluded from the building quote even where the contractor coordinates the related work.
Check the Payment Schedule
A quote may include a proposed payment structure.
Make sure you understand:
- Deposit
- Stage payments
- Interim valuations
- Final payment
- Retention where applicable
Payments should make sense in relation to the work being carried out.
A quote that requires a large proportion of the contract price before equivalent progress has been made deserves careful review.
Check What the Deposit Covers
If the builder asks for a deposit, ask why.
It may relate to:
- Advance materials
- Bespoke windows
- Structural steel
- Kitchen orders
- Specialist products
The reason should be transparent.
Check the Construction Programme
The quote may state a duration or expected start date.
Ask:
- When can the project start?
- How long is it expected to take?
- Does the builder have other projects running?
- Are any long-lead items likely to affect the programme?
- Heating equipment
A very short proposed programme can be just as questionable as an excessively long one if it does not match the amount of work involved.
Check Whether the Quote Is Fixed
Ask whether the price is:
- Fixed
- Estimated
- Subject to review
- Based on allowances
- Dependent on material prices
The terminology matters.
A quotation can still contain variable elements even where there is a headline total.
check a builder Contract
Check Whether Liquidated Damages Apply
Some contracts include a pre-agreed amount payable if the contractor completes late without an allowable reason.
These are often called liquidated damages.
They are not appropriate in every situation.
If included, the amount should be clearly stated and should reflect a genuine estimate rather than simply being punitive.
Check How Variations Are Handled
Changes are common during construction.
The contract should explain how variations are:
- Requested
- Priced
- Approved
- Recorded
Ideally, changes should be confirmed in writing.
Check Who Can Authorise Changes
Establish who has authority to instruct changes.
This can be particularly important where several people are involved.
For example:
- Homeowner
- Architect
- Project manager
- Builder
The contractor should know whose instructions are valid under the contract.
Check How Additional Costs Are Approved
Before extra work proceeds, the contract should ideally provide a clear process for:
- Identifying the change
- Pricing it
- Agreeing the cost
- Recording any programme effect
This can reduce arguments about unexpected extras later.
Check Unforeseen Work
Existing buildings can hide problems.
These might include:
- Structural defects
- Damp
- Rotten timber
- Drainage issues
- Poor previous work
The contract should explain what happens when something genuinely unforeseen is discovered.
Check Who Is Responsible for Materials
Clarify responsibility for:
- Ordering
- Payment
- Delivery
- Storage
- Damage
This is particularly important for expensive or long-lead items.
Check Ownership of Materials
Where materials are paid for before installation, consider when ownership passes to the client.
This may matter if:
- The contractor becomes insolvent
- Materials are stored off site
- A dispute occurs
The contract should deal with this clearly where relevant.
check a builder Contract
Check Snagging
Minor defects and incomplete items may be recorded in a snagging list.
The contract should make clear:
- Who prepares the list
- When items should be completed
- Whether payment depends on completion
Check the Defects Period
Some contracts include a period after completion during which identified defects can be reported for correction.
Check:
- Length of the period
- How defects are notified
- When remedial work should be undertaken
Check Warranties and Guarantees
Certain products or systems may come with warranties.
Examples include:
- Roofing
- Windows
- Boilers
- Waterproofing
- Specialist products
Ask who will provide these documents at completion.
Check Termination Clauses
The contract should explain the circumstances in which either party can end the agreement.
This can include serious situations such as:
- Non-payment
- Abandonment
- Persistent breach
- Insolvency
Termination provisions can have significant consequences, so they should be understood before signing.
Check What Happens if the Builder Stops Work
This is not something anyone expects when appointing a contractor, but the contract should still deal with it.
Consider:
- Notice requirements
- Payment for completed work
- Materials on site
- Securing the property
- Bringing in another contractor
Check What Happens if You Want to End the Contract
Clients may also have reasons for wanting to terminate.
Do not assume you can simply dismiss a contractor without contractual consequences.
The correct process will depend on the agreement.
Check Dispute Resolution
The contract should explain what happens if a dispute arises.
This may involve:
- Negotiation
- Mediation
- Adjudication
- Arbitration
- Court proceedings
The appropriate mechanism depends on the contract and dispute.
check a builder contract
Check Whether Verbal Agreements Are Being Left Outside the Contract
This is a common source of problems.
If something important has been agreed verbally, make sure it appears somewhere in the written contractual documents.
Examples include:
- Builder supplying flooring
- Client supplying sanitaryware
- Specific completion deadline
- Agreed discount
- Particular material
If it matters, write it down.
Check for Conflicting Documents
Sometimes the contract documents contradict one another.
For example:
- Drawing shows one material
- Specification states another
- Quotation excludes something shown in the scope
These conflicts should be resolved before signing.
Check the Order of Precedence
Some contracts explain which document takes priority where documents conflict.
For larger projects, this can be important.
You should understand which information governs if:
- Contract
- Drawings
- Specification
- Quotation
do not say exactly the same thing.
Check Amendments to Standard Contracts
Standard building contracts are often amended.
If clauses have been:
- Deleted
- Rewritten
- Added
make sure you understand what effect those changes have.
A familiar contract title does not necessarily mean the document remains standard.
Do Not Sign a Contract You Do Not Understand
Construction contracts can contain technical or legal language.
If a clause has significant financial or legal implications and you are unsure what it means, obtain appropriate professional or legal advice before signing.
It is much easier to clarify a contract before work begins than after a dispute develops.
How Tholos Can Help Review a Builder Contract
Where Tholos is involved in the project, we can help check whether the construction documents align with the design and agreed scope.
Depending on the service, this may include:
- Checking drawings referenced in the contract
- Reviewing scope consistency
- Comparing quotation and design information
- Identifying missing or conflicting project information
- Highlighting areas requiring clarification
- Helping define construction responsibilities
Architectural review is not a substitute for legal advice where legal interpretation is required.
But it can help make sure the contract reflects the project you actually intend to build.
Builder Contract Checklist
Before signing, check:
- Correct client
- Correct contractor
- Property address
- Scope of works
- Drawing revisions
- Specification
- Builder quotation
- Contract price
- VAT
- Exclusions
- Allowances
- Deposit
- Payment schedule
- Start date
- Construction period
- Completion date
- Delays
- Variations
- Materials
- Insurance
- Access
- Building Control
- Certification
- Completion process
- Defects
- Termination
- Dispute procedure
Anything important that is unclear should be resolved before the contract is signed.
Client experience
"
Lorem ipsum dolor sit amet, consectetur adipiscing elit. We had a vision for our home but no idea how to realise it. Tholos Interiors took complete ownership of the project — every detail was considered, every decision explained. The result exceeded everything we had imagined.
– Lawrence Ipsum, Homeowner · London –
Frequently Asked Questions
Do I need a contract with a builder?
For significant construction work, a written contract provides much greater clarity than relying only on verbal discussions.
It can define the scope, price, programme, payments and responsibilities.
Is a builder’s quote a contract?
A quotation may form part of an agreement, but it may not deal with all the issues that a more complete building contract would address.
For substantial projects, relying only on a quotation can leave important matters undefined.
What should I check in a building contract?
Check the parties, scope, drawings, price, exclusions, payments, programme, delays, variations, insurance, completion provisions and dispute procedure.
Should the builder contract refer to the drawings?
Where architectural or technical drawings define the work, they should normally be clearly identified within the contractual information.
Make sure the correct revisions are referenced.
What happens if the builder finishes late?
That depends on the contract and reason for the delay.
The contract may allow extensions of time in certain circumstances and may contain provisions for contractor-caused delay.
Check the Contract Before Construction Starts
A building contract should reflect the project you have actually agreed.
It should align with:
- The drawings
- The quotation
- The scope
- The programme
- The payment arrangement
If those documents tell different stories, problems can emerge later.
Reviewing the contract carefully before signing gives both client and builder a clearer basis for delivering the project.
Disclaimer
This article is part of a series created by our dynamic marketing team for informational purposes only. While we strive to review all content thoroughly, occasional oversights may occur, even after publication. Therefore, we cannot accept liability for any interpretations or use of the information provided. For the most up-to-date information or to report any discrepancies, please contact us at hello@tholos-architects.com.
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