Section 1
Purpose
Note on JCT editions: JCT has published the 2024 Edition. This guidance cites JCT SBC/Q 2016 clause references; the commercial and payment mechanisms are substantively unchanged in the 2024 edition, but specific clause references should be verified against the contract edition in use on any given project.
Completion Assessment is the formal process by which the Contract Administrator and the QS determine whether the works have reached a state sufficiently complete to justify the issue of the Certificate of Practical Completion (CPC). The QS's role is advisory and financial: assessing the outstanding items, advising on the contractual implications of any premature or delayed certification, and ensuring that all associated financial transactions are triggered correctly and on time.
Under English law and RICS guidance, 'practical completion' has no single statutory definition but is established through case law. RICS Defining Completion of Construction Works (1st edition, July 2011; reissued August 2024 as RICS practice information) consolidates the principles from key cases including Hoenig v Isaacs [1952] and Jarvis v Westminster Corporation [1970], establishing that PC is reached when the works are complete for all practical purposes — minor snagging does not prevent PC but the existence of known material defects at the time of certification may undermine the certificate.
Correct and timely PC certification is critical: the PC date determines when LADs cease, when the first moiety of retention is released, when the Rectification Period commences, and when the contractor's obligation to insure the works ends. Errors in the PC date have direct financial consequences for the client.
Section 2
Key Principles
- RICS Defining Completion of Construction Works (1st edition, July 2011; reissued August 2024 as RICS practice information): PC is the state in which the works are complete for all practical purposes; sectional completion is valid where the contract provides for it; partial possession does not equate to PC.
- JCT SBC/Q 2016 clause 2.30: the Architect/Contract Administrator certifies Practical Completion when the works are practically complete. Clauses 2.33–2.37 allow the employer, with the contractor's consent, to take partial possession of any part of the works: practical completion of the Relevant Part is deemed to have occurred on the Relevant Date (clause 2.34), releasing half the retention on that part, and liquidated damages for the remainder are reduced pro rata (clause 2.37). Note that clause 2.32 is liquidated damages, not partial possession.
- Case law — Hoenig v Isaacs [1952]: substantial performance sufficient for the main contract sum to be due; Jarvis v Westminster [1970]: trivial defects do not prevent PC. PC cannot be withheld for trivial snagging.
- RICS Defects and Rectifications (2nd edition, August 2024): distinguishes patent defects (visible at inspection), latent defects (hidden, discoverable within the limitation period), and design defects; each has different liability and remedies.
- NEC4 Clause 30.2: the Project Manager certifies Completion within one week of the Contractor achieving it; Completion is defined in the Works Information/Scope. Under NEC4 Clause 35, the Employer may take over any part before Completion.
- HGCRA 1996 (as amended): once PC is certified, the first moiety of retention becomes due; the Architect/Contract Administrator must issue the Interim Certificate not later than 5 days after the due date (JCT Clause 4.9.1), on the QS's interim valuation (Clause 4.9.2); if it is not issued, the contractor's Interim Application stands as the Payment Notice and fixes the notified sum by default (Clause 4.10.2).
Section 3
Practical Application
Step 1
Before the PC inspection: review the contractor's own snagging list, prepare a pre-inspection review checklist, and brief the CA on any outstanding financial items that require resolution before or at PC (e.g. unresolved LAD periods).
Step 2
Attend the PC inspection with the CA and the full design team; record all observed defects and outstanding items on the Schedule of Defects; categorise items as material/minor and identify any items that could prevent PC.
Step 3
Assess the financial implications of the proposed PC date: calculate the LAD saving (if any) versus the contractual completion date; identify the first moiety retention amount; confirm the Rectification Period end date and Final Certificate deadline.
Step 4
Advise the CA on any items that genuinely prevent PC (material/known defects at time of inspection) versus items that may be noted on the Schedule of Defects; document your advice in writing to create an audit trail.
Step 5
Once the CPC is issued, immediately instruct the first moiety retention release via a formal payment notice compliant with HGCRA and the contract; confirm the PC date in writing to the contractor.
Step 6
Where sectional completion applies (JCT SBC/Q 2016 Contract Particulars), manage each section's PC date, retention moiety, and Rectification Period separately; maintain a sections register to track each independently.
Step 7
Where partial possession occurs under JCT SBC/Q 2016 clauses 2.33–2.34, calculate the pro-rata retention release on the estimated value of the part taken into possession; document the partial possession date and area.
Section 4
Common Mistakes to Avoid
- Advising the CA to withhold PC because of minor snagging — this can expose the employer to unliquidated damages claims from the contractor for the period beyond the contractual completion date.
- Failing to confirm the PC date in writing immediately after the inspection — ambiguity about the PC date creates LAD calculation disputes and retention release disputes.
- Overlooking the distinction between sectional and overall completion — PC for one section does not trigger events for others; each section's retention and Rectification Period must be tracked independently.
- Failing to issue the payment notice for the first moiety retention release promptly — under HGCRA, a failure to issue the Interim Certificate within 5 days of the due date (JCT Clause 4.9.1) means the contractor's Interim Application stands as the Payment Notice and becomes the notified sum by default (JCT Clause 4.10.2).
- Treating partial possession (clauses 2.33–2.34) and practical completion as equivalent. Partial possession deems practical completion of the Relevant Part only: the Rectification Period for that part runs from the Relevant Date, half the retention on it is released, and liquidated damages are reduced pro rata under clause 2.37 — but the works as a whole remain incomplete. Do not confuse clause 2.32, which is liquidated damages.
Section 5
APC Competency & Quick Reference
- Contract Practice Level 3 — advising on Practical Completion, sectional completion, partial possession, and associated retention/LAD implications
- Legal and Regulatory Compliance Level 2 — understanding of case law on PC, HGCRA payment obligations
What is the legal test for Practical Completion and what is the QS's role in the process?
PC is reached when the works are complete for all practical purposes (Hoenig v Isaacs [1952]; Jarvis v Westminster [1970]). Minor snagging does not prevent PC. The QS's role is advisory: assessing the financial implications of the PC date, advising the CA, ensuring the first moiety retention is released promptly, and confirming the Rectification Period/Final Certificate timetable.
What happens if a contractor is certified as practically complete but material defects are later discovered?
Material defects known at the time of PC certification may undermine the certificate (RICS Defining Completion, 2024). If defects emerge during the Rectification Period, the contractor must rectify under JCT Clause 2.38. Latent defects discovered after the Rectification Period may still be recovered within the limitation period (6 years for simple contract; 12 years for deed).
How does partial possession under JCT SBC/Q 2016 clauses 2.33–2.37 affect retention?
Upon partial possession, the Employer becomes entitled to a pro-rata retention release on the estimated value of the part. The Rectification Period for that part runs from the partial possession date. PC for the whole works has not been certified and the contractor's full retention continues on the remaining works.
Section 6
Completion & Final Account Checklist
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Task
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PC inspection attended with CA and design team
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Schedule of Defects prepared — material items identified
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PC date confirmed in writing to contractor and CA
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First moiety retention release payment notice issued within HGCRA timescales
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LAD cessation date confirmed and any deduction amount notified to client
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Rectification Period end date and Final Certificate deadline calculated and recorded
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Sectional/partial possession sections tracked separately where applicable
Section 7
CPD Learning Outcomes
- Apply the legal and RICS principles of Practical Completion to advise the Contract Administrator and client on completion certification decisions and their financial consequences.
- Calculate and instruct the first moiety retention release in compliance with HGCRA 1996 and JCT SBC/Q 2016 payment notice requirements.
- Distinguish between patent, latent, and design defects and advise on the appropriate contractual and legal remedies for each category.
Section 8
Further Reading
- RICS, Defining Completion of Construction Works, 1st edition, August 2024
- RICS, Defects and Rectification, 2nd edition (Black Book)
- JCT Standard Building Contract with Quantities 2016 — clauses 2.30 (Practical Completion), 2.32 (liquidated damages), 2.33–2.37 (partial possession), 2.38–2.39 (Rectification Period and Certificate of Making Good), 4.17–4.19 (Retention)
- NEC4 Engineering and Construction Contract — Clauses 30.2, 35
- Hoenig v Isaacs [1952] 2 All ER 176; Jarvis v Westminster Corporation [1970] 1 WLR 637
- RICS, Retention, GN 90/2012 — retention release at PC
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