FIDIC Clause 5.8 [Design Error] Explained: Responsibilities, Risks & Real-World Scenarios (1999 vs 2017)

1️⃣ Purpose of Clause 5.8 [Design Error]

1999 Edition: The purpose of Clause 5.8 [Design Error] is to establish a clear and unambiguous responsibility on the Contractor for any errors, omissions, ambiguities, inconsistencies, inadequacies, or defects found in the Contractor’s Documents. These “Documents” include the design-related deliverables prepared by the Contractor under the Contract, such as drawings, specifications, manuals, calculations, and other technical materials (as defined in Clause 1.1.6.1).

✅ This clause effectively safeguards the Employer’s interests by ensuring the Contractor cannot later shift the blame to the Engineer or claim that prior approval absolves them of responsibility.

📌 Implications for the Parties:

• Contractor: Fully liable for quality and correctness of their design documentation, even post-approval.
• Engineer: Can approve or comment but does not assume liability through their actions.
• Employer: Gains protection from downstream issues caused by design defects.

2017 Edition: This clause maintains the same core objective of contractor accountability, but introduces a more structured, integrated approach by:

1. Expanding coverage to include the Contractor’s actual design, not just documentation.
2. Explicitly directing the resolution process through Sub-Clause 7.5 [Defects and Rejection].
3. Clarifying the contractual effect of a prior Notice of No-objection given by the Engineer (under Sub-Clause 5.2.2).

✅ This evolution reflects FIDIC’s increased focus on clarity and integrated defect resolution processes.

📌 Practical Enhancements:

• Greater procedural guidance for how design errors are to be corrected.
• Emphasis on risk retention by the Contractor despite Engineer’s No-objection.
• Reduction of ambiguity around the Engineer’s review function.

🕰️ Historical Context: The 2017 version arose in response to:

• Disputes around Engineer approvals being perceived as “certifications.”
• Increasing legal pressure for clarity in design-build contracts.
• The desire to link quality issues to structured processes (e.g., Clause 7.5).

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2️⃣ Breakdown of Clause 5.8 [Design Error]

📜 1999 Edition Full Text:

“If errors, omissions, ambiguities, inconsistencies, inadequacies or other defects are found in the Contractor’s Documents, they and the Works shall be corrected at the Contractor’s cost, notwithstanding any consent or approval under this Clause.”

🧠 Key Terms Explained:

• Errors, omissions, ambiguities, inconsistencies, inadequacies, or other defects: Broad language captures a wide range of potential issues, from technical calculation errors to misalignments between documents.
• Contractor’s Documents: Defined in Clause 1.1.6.1, includes all technical deliverables.
• Shall be corrected: Mandatory language indicating non-negotiable obligation.
• At the Contractor’s cost: The burden is entirely on the Contractor, reinforcing risk allocation.
• Notwithstanding any consent or approval: Even if the Engineer reviewed and approved the documents, liability remains with the Contractor.

📜 2017 Edition Full Text:

“If errors, omissions, ambiguities, inconsistencies, inadequacies or other defects are found in the Contractor’s design and/or the Contractor’s Documents, they and the Works shall be corrected in accordance with Sub-Clause 7.5 [Defects and Rejection]. If such Contractor’s Documents were previously the subject of a Notice of No-objection given (or deemed to be given) by the Engineer under Sub-Clause 5.2.2 [Review by Engineer], the provisions of Sub-Clause 5.2.2 shall apply as if the Engineer had given a Notice in respect of the Contractor’s Documents under sub-paragraph (b) of Sub-Clause 5.2.2.
All corrections and resubmissions under this Sub-Clause shall be at the Contractor’s risk and cost.”

🧠 Expanded and Clarified:

• Adds “Contractor’s design” to clarify liability includes original engineering decisions, not just documentation.
• Embeds compliance with Clause 7.5, thus connecting to a formal defect rejection and remedy procedure (e.g., timelines, inspection obligations).
• Introduces nuanced handling where the Engineer has previously issued a Notice of No-objection — doesn’t eliminate Contractor liability but adjusts procedural consequences.
• Final sentence reinforces that risk and cost remain with the Contractor, preserving the principle of self-responsibility.

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3️⃣ Key Interpretations and Implications

🚨 Absolute Liability for Design Quality:

Even with Engineer approval or No-objection, the Contractor cannot escape liability for design flaws.

✅ Risk Is Not Shifted by Engineer’s Review:

In both editions, whether the Engineer approved or gave No-objection has no bearing on the Contractor’s liability. This addresses a common misconception in disputes.

📌 Introduction of Clause 7.5 in 2017:

• Brings in a formal mechanism for rejection, timelines for remedy, and the Contractor’s duty to respond.
• Creates a more controlled and auditable correction pathway.

💡 Implications of the No-Objection Clause:

• 1999: Does not distinguish between approval and review types.
• 2017: Differentiates formal “No-objection” (non-binding) and explains its procedural role. See Sub-Clause 5.2.2(b), which allows the Engineer to re-invoke correction obligations without contractual conflict.

📎 Summary of Impacts:

• 🛠️ Contractor must design, review, and check rigorously — internal QA/QC is critical.
• 🧾 Employer is insulated from liability, even for approved documents.
• ⚖️ Dispute boards and arbitral panels have clearer grounds to enforce Contractor liability.

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4️⃣ Cross-Referencing with Other Clauses

“How does Clause 5.8 play with its clause-friends across the contract?”
Great question. Let’s unpack this step by step.

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🎯 Core Idea Behind Cross-Referencing

Think of Clause 5.8 [Design Error] as a watchdog guarding the quality of design inputs. But this watchdog isn’t barking in isolation — it interacts with several other clauses that shape what happens before, during, and after a design error shows up.

We’ll walk through the key supporting cast that give 5.8 its practical teeth.

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🧩 1999 Edition — Cross-Linked Clauses

📌 Clause 1.8 [Care and Supply of Documents]

Before anything is reviewed or constructed, this clause ensures the Contractor keeps the design documents on site and is responsible for their safekeeping.

💡 Relevance to Clause 5.8:

• If something goes wrong in the Contractor’s Documents, they can’t claim “oops, I lost the file!” They’re fully responsible for having and maintaining accurate, up-to-date designs.

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📌 Clause 5.2 [Contractor’s Documents]

This one sets the scene for how designs are prepared, submitted, and reviewed.

🛠️ The Engineer reviews the Contractor’s Documents and can either approve them or request changes. But—and here’s the kicker—even if the Engineer gives a green light, Clause 5.8 still puts the risk squarely on the Contractor.

⚠️ Contractor Trap to Avoid:

“But the Engineer approved this!”
Nope! Clause 5.8 is crystal clear: approval doesn’t mean liability transfer.

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📌 Clause 3.5 [Engineer’s Determinations]

Here’s the judge in our contract court. If a dispute arises about whether something really is a “design error” or not, the Engineer is empowered to make a determination.

💬 Why it matters: If the Contractor resists a correction citing it’s “not a true error,” the Engineer can decide under this clause—and Clause 5.8 kicks in to say the Contractor must correct at their cost if the determination goes against them.

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📌 Clause 11.1 [Completion of Outstanding Work and Remedying Defects]

This one governs the Defects Notification Period. If a design error manifests after practical completion, Clause 11.1 works in tandem with Clause 5.8 to ensure the Contractor still fixes it—no escape!

✅ It’s not “out of sight, out of mind” once you hand over the keys.

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⚙️ 2017 Edition — Cross-Linked Clauses

The 2017 edition tightens up the web of connections even more.

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📌 Clause 5.2.2 [Review by Engineer]

This is the upgraded, clearer version of the review process. It introduces the term “Notice of No-objection” — which replaces vague approvals.

🎯 Key takeaway: Even if the Engineer says “no objection,” the Contractor is still on the hook for any errors in the design. Clause 5.8 spells this out by looping back to 5.2.2 and clarifying that No-objection ≠ Design Approval.

💬 Think of this like a teacher saying, “You may proceed with your project,” not “I promise this will work.”

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📌 Clause 7.5 [Defects and Rejection]

This is a BIG one.

In the 2017 edition, if there’s a design error, you don’t just “fix it and move on.” Now it kicks off a formal process:

1. Engineer rejects the defective Works or design.
2. Contractor gets notified and must remedy the issue within a defined timeframe.
3. The whole cycle becomes traceable, manageable, and enforceable.

📌 Clause 5.8 in 2017 explicitly refers to 7.5 — giving design corrections structure, enforceability, and a timeline.

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📌 Clause 3.7 [Agreement or Determination]

In case there’s disagreement over whether the Contractor’s design is actually defective, this clause kicks in.

🌐 Think of it like a decision hub:

• First, the Parties try to agree.
• If that fails, the Engineer issues a determination.
• If someone still disagrees, they can escalate via the Dispute Avoidance/Adjudication Board (DAAB).

This gives Clause 5.8 backup in disputes: if the Contractor resists a correction, the contract has a defined route to resolve it.

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📌 Clause 11.1 [Completion of Outstanding Work and Remedying Defects]

As with 1999, any issues discovered after the Works are handed over — even during the Defects Notification Period — still require correction.

📎 In practice: if a faulty design causes a problem 6 months post-handover, Clause 5.8 + 11.1 = “Contractor, fix it on your dime.”

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🔗 Supporting Players

• Clause 4.1 [Contractor’s General Obligations]: Binds the Contractor to deliver a complete and functional design.
• Clause 4.9 [Quality Management]: The Contractor should have quality systems in place to catch design errors before submission.

Together, they give real-world strength to Clause 5.8 — it’s not just about what to do after something goes wrong, it’s also about how to prevent errors in the first place.

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📌 Summary Table: Clause 5.8 Interactions

Related Clause	Edition	Purpose	Why It Matters to 5.8
1.8	1999	Care of Documents	Contractor owns and manages design data
5.2	1999	Document Submission	Starts the Engineer review process
3.5	1999	Engineer’s Determination	Resolves disputes about what is an “error”
11.1	Both	Defect Rectification	Design issues post-handover must still be fixed
5.2.2	2017	Review by Engineer	No-objection ≠ No liability
7.5	2017	Defects & Rejection	Gives a procedural path to corrections
3.7	2017	Agreement/Determination	Dispute path if error is denied
4.1 & 4.9	2017	General Obligations & Quality	Contractor must prevent and fix design flaws

5️⃣ What-If Scenarios?

💭 Scenario 1:

Contractor’s HVAC system design has an airflow miscalculation discovered during commissioning. The Engineer had previously issued a No-objection.

• 1999: Contractor must correct at their own cost; No-objection has no protective value.
• 2017: Same outcome. Correction must be made in accordance with Clause 7.5, and No-objection is acknowledged but doesn’t shield the Contractor.

💭 Scenario 2:

The Engineer fails to spot a structural error during document review and gives full approval. Later, the error causes a construction delay.

• Contractor still bears cost and time impact.
• Possible recourse: Clause 20 (Claims) if delay was exacerbated by Engineer’s action — but design error correction cost is still non-recoverable.

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6️⃣ Suggestions for Clarity and Improvement

“What could we tweak in Clause 5.8 to make life easier for everyone?”

When a clause holds such significant liability and technical complexity, the smallest ambiguity can lead to big disputes. Let’s break down how Clause 5.8 can sometimes create confusion—and how we might clarify it using smart drafting, illustrative examples, and clear definitions.

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🎯 1. Clarify What Qualifies as a “Design Error”

Right now, both versions of Clause 5.8 refer broadly to:

“errors, omissions, ambiguities, inconsistencies, inadequacies or other defects…”

📌 What’s unclear?
These terms are not defined anywhere in the General Conditions.

🧩 Why it matters:
Contractors and Employers may interpret these differently. For instance:

• Is a design that meets performance specs but uses unconventional methods an error?
• Is a lack of detailing in the drawing an “omission” or just incomplete scope?

✅ Suggested Improvement:

🔍 Include a definition or Annex defining “Design Error” with categories like:

• Calculation mistake (e.g., miscalculated beam load)
• Code non-compliance (e.g., not meeting Eurocode 2 for concrete design)
• Functional failure (e.g., HVAC not delivering airflow required)
• Ambiguity in instructions (e.g., conflicting dimensions between sections)

🧠 Example:

If the Contractor’s drawings show a beam size of “300mm x 400mm” in one section and “450mm x 600mm” in another, is this an “ambiguity” or just a mistake?
Clause 5.8 should explicitly handle these inconsistencies by example or definition.

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🎯 2. Make the Engineer’s “No-objection” Meaning Crystal Clear

In 2017, the clause does a better job by referencing Sub-Clause 5.2.2, but there’s still room to clarify what a “No-objection” means—and more importantly, what it doesn’t mean.

📌 Common Misunderstanding:

“The Engineer gave me a No-objection, so if there’s a problem, it’s their fault.”
Wrong! But the wording could do more to close the door on that line of argument.

✅ Suggested Improvement:

Add a statement in Clause 5.8 like:
“For the avoidance of doubt, the Engineer’s Notice of No-objection under Sub-Clause 5.2.2 shall not relieve the Contractor of any obligation or liability under this Sub-Clause.”

🧠 Example:

Let’s say the Contractor designs a retaining wall using soil anchors. The Engineer issues a No-objection. Months later, it collapses due to under-designed anchorage lengths.

👉 The Contractor might argue: “But I got a No-objection!”
A stronger Clause 5.8 would squash this by stating the No-objection doesn’t shift liability.

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🎯 3. Introduce Timeframes for Corrections

Currently, Clause 5.8 says errors “shall be corrected,” but doesn’t specify how quickly.

📌 That’s risky. Why?
Without deadlines, a Contractor might delay action, claiming they’re “assessing” or “waiting for redesign.”

✅ Suggested Improvement:

Add a phrase like:
“The Contractor shall propose corrective measures within 7 days of being notified of the error and complete corrections within a reasonable period, as instructed by the Engineer.”

🧠 Example:

A pump station design has the wrong pipe gradients. The Engineer finds this issue during review. Without a deadline, the Contractor could stall. With a timeline built in, it triggers immediate action.

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🎯 4. Specify Consequences for Non-Compliance

While the clause says the Contractor must correct at their “own cost and risk,” it doesn’t explicitly link failure to correct with the Employer’s right to step in or claim damages.

📌 That’s a gap you don’t want during a live project!

✅ Suggested Improvement:

Add language such as:
“If the Contractor fails to correct any design error within the timeframe stated by the Engineer, the Employer shall be entitled to engage third parties to perform such corrections, and recover the associated costs from the Contractor.”

🧠 Example:

Let’s say the electrical design fails to consider voltage drop over long cable runs. The Contractor refuses to acknowledge the issue. Under this enhanced clause, the Employer can fix it and backcharge.

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🎯 5. Reference Technical Standards for Evaluation

When does an error really count as an error? Without a benchmark, it’s subjective.

📌 Smart move: tie design obligations to specific codes or industry standards, where possible.

✅ Suggested Improvement:

“The Contractor’s design shall comply with the Employer’s Requirements and with applicable codes such as [e.g., ISO, EN, ASME, NFPA] unless otherwise specified. Design errors shall be evaluated with reference to these standards.”

🧠 Example:

An MEP subcontractor designs HVAC ducting using outdated ASHRAE guidelines. This leads to insufficient air changes. Clause 5.8 would benefit from referencing ASHRAE or relevant standards as the benchmark for “error.”

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🎯 6. Encourage Internal QA and Peer Review

Right now, Clause 5.8 assumes design will be correct—but doesn’t encourage the Contractor to adopt preventive measures.

📌 If we want fewer design errors, let’s build quality into the contract, not just react to mistakes.

✅ Suggested Improvement:

Require that the Contractor include a peer-review process or design verification checks as part of their Quality Assurance Plan under Clause 4.9.

🧠 Example:

Require something like:

“Each critical design element shall be reviewed and signed off internally by a qualified engineer who did not prepare the original design.”

🎯 This not only prevents design errors—it gives the Employer a clearer picture of the Contractor’s competence and accountability.

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🔚 Final Summary of Section 6 Suggestions

Area	Issue	Proposed Fix	Example
Definition	Broad terms like “errors” undefined	Add glossary or examples	Misaligned column sizes
No-objection	Misinterpreted as approval	Explicit disclaimer	Retaining wall failure
Timeframes	No urgency for fixes	Add deadlines for response and correction	Pipe gradient error
Consequences	No stated remedy for inaction	Employer can step in and charge	Electrical voltage issue
Standards	No objective criteria	Reference codes like EN, ISO	HVAC air flow misdesign
Prevention	No QA process required	Mandate design peer-review	Structural design check

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7️⃣ Final Takeaways

📌 Key Insights:

• Both editions maintain strong accountability for design quality on the Contractor.
• 2017 improves procedural clarity and links design error resolution into defect control workflows.
• No-objection ≠ approval — a critical distinction to educate project teams on.

🎯 Practical Applications:

• Contractors should implement rigorous design verification, peer review, and internal sign-off.
• Employers can rely on this clause as a risk shield — especially helpful in multi-disciplinary, design-heavy projects.

✅ Clause 5.8 Compliance & Quality Control Checklist

(FIDIC Yellow Book 1999 & 2017 Editions)

🔍 For Contractors: Pre-Submission Design Review

Item	Description	✅ Check
1	Have all design calculations been verified independently?	☐
2	Are all drawings and specifications internally peer-reviewed?	☐
3	Do the design documents comply with the Employer’s Requirements?	☐
4	Are applicable technical standards (e.g., EN, ISO, ASME) clearly followed and cited?	☐
5	Are all design assumptions documented and traceable?	☐
6	Are all drawing revisions recorded and change logs maintained?	☐
7	Have ambiguities and inconsistencies between drawings and specifications been resolved?	☐
8	Has a design QA/QC checklist been completed and signed off internally?	☐
9	Has Clause 5.8 been reviewed with the design team for liability awareness?	☐

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🧰 For Engineers: Design Review & No-Objection Checks

Item	Description	✅ Check
1	Was the review completed within the stipulated review period (see Clause 5.2.2)?	☐
2	Has the Engineer refrained from issuing “approvals” and instead used “No-objection” where applicable?	☐
3	Were any comments or rejections properly documented and communicated?	☐
4	Has the Engineer verified that the Contractor understands that a No-objection does not transfer liability?	☐
5	Have previous issues or known design risks been addressed in the current submission?	☐
6	Has the Engineer maintained a record of all No-objection notices issued?	☐

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🛠️ For Contractors: Responding to Identified Design Errors (Post-Submission)

Item	Description	✅ Check
1	Has the Contractor acknowledged the design error in writing?	☐
2	Has a correction plan been submitted within the required period (suggested: 7 days)?	☐
3	Has the Engineer approved or rejected the proposed correction method?	☐
4	Are all associated Works affected by the design error being revised simultaneously?	☐
5	Have costs and delays been evaluated internally for possible claims under Clause 20 (if applicable)?	☐
6	Has the Contractor ensured that similar errors are not repeated in other areas of the design?	☐

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⚖️ For Employers: Oversight & Risk Mitigation

Item	Description	✅ Check
1	Is the Contractor’s QA system compliant with Clause 4.9?	☐
2	Are there protocols to ensure timely Engineer reviews of Contractor’s Documents?	☐
3	Have disputes arising from design error been tracked and escalated properly (via Clause 3.7 or Clause 21)?	☐
4	Is the Employer’s team aware that even with Engineer No-objection, liability remains with the Contractor?	☐
5	Have provisions for backcharging corrections (if Contractor fails to act) been clearly understood?	☐

📄 Sample Letter

📄 Sample Letter #1: Engineer Notifies Contractor of a Design Error

Scenario: The Engineer has discovered a design inconsistency in the Contractor’s Documents.

Title: Notice of Design Error – Request for Correction

[Engineer’s Letterhead]
[Date]

To: [Contractor’s Name]  
[Contractor’s Address]  

Subject: Notice of Design Error – Clause 5.8 [Design Error]

Dear [Contractor’s Representative],

We refer to your submission dated [Submission Date] concerning [Description of Document – e.g., Structural Design Drawings for Pump Station].

Upon review, we have identified the following issue:  
[Briefly describe the issue – e.g., The beam sizing shown in Section A-A (300mm x 400mm) conflicts with Section B-B (450mm x 600mm)].

In accordance with **Clause 5.8 [Design Error]**, you are hereby notified that the above constitutes a design inconsistency. You are requested to:
- Provide corrected documents, and
- Propose corresponding corrective measures for the Works already executed (if applicable),

within **[insert reasonable period, e.g., 7 days]** from the date of this Notice.

Please note, as per Clause 5.8, all such corrections shall be at your own risk and cost, notwithstanding any prior Notice of No-objection provided.

Yours faithfully,  
[Engineer’s Name]  
[Title]  
cc: Employer

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📄 Sample Letter #2: Contractor Responds Acknowledging the Design Error

Scenario: Contractor agrees there is a design error and outlines the corrective action.

Title: Acknowledgement and Corrective Action for Design Error

[Contractor’s Letterhead]  
[Date]

To: [Engineer’s Name]  
[Engineer’s Address]

Subject: Response to Notice of Design Error – Clause 5.8

Dear [Engineer’s Name],

We acknowledge receipt of your Notice dated [Engineer’s Letter Date] regarding the design inconsistency in [Description of Documents].

Upon internal review, we confirm that an error exists in the submitted design documents. In accordance with **Clause 5.8 [Design Error]**, we propose the following corrective actions:
1. Revision of the affected drawing [Drawing No. XYZ], with corrected dimensions.
2. Removal and reconstruction of the Works already affected, namely [describe works], to align with the updated design.

The revised documents are enclosed herewith for your review. We confirm that the above actions will be undertaken at our own cost and risk.

Kindly confirm if the proposed measures meet your requirements so we may proceed without delay.

Yours sincerely,  
[Contractor’s Representative]  
[Title]  
cc: Employer

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📄 Sample Letter #3: Contractor Disputes the Alleged Design Error

Scenario: Contractor believes the design is correct and disputes the Engineer’s Notice.

Title: Response to Alleged Design Error – Request for Determination

[Contractor’s Letterhead]  
[Date]

To: [Engineer’s Name]  
[Engineer’s Address]

Subject: Dispute of Design Error Allegation – Clause 5.8

Dear [Engineer’s Name],

We refer to your Notice dated [Date] alleging a design error in [Document Name or Section].

Following a detailed review, we respectfully disagree with the assertion that the subject matter constitutes a design error. Our submission complies with the applicable standards [specify standard/code], and was developed in accordance with the Employer’s Requirements.

Given the differing views, we hereby request that the matter be addressed under **Clause 3.7 [Agreement or Determination]**. We remain committed to resolving this issue promptly and professionally.

Please advise on the next steps for consultation.

Yours faithfully,  
[Contractor’s Representative]  
[Title]  
cc: Employer

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📄 Sample Letter #4: Employer Backcharges Contractor for Failure to Correct Error

Scenario: Contractor failed to correct the design error, so the Employer engaged a third party to do so.

Title: Recovery of Costs for Unrectified Design Error – Clause 5.8

Employer’s Letterhead]  
[Date]

To: [Contractor’s Name]  
[Contractor’s Address]

Subject: Cost Recovery for Third-Party Correction – Clause 5.8

Dear [Contractor’s Representative],

We refer to the unresolved design error concerning [Design Topic] notified by the Engineer on [Date], and your failure to provide or implement a timely correction.

In accordance with **Clause 5.8 [Design Error]**, and due to your non-compliance, we engaged an independent third party to implement corrective works. The total cost incurred was [insert amount], supported by the attached invoices.

This amount will be deducted from your next interim payment, or otherwise recovered per the terms of the Contract.

Yours sincerely,  
[Employer’s Representative]  
[Title]  
cc: Engineer