What Is Practical Completion — Really?
You’d think there’d be a clear definition for such an important milestone.
But under most JCT contracts, one of the most widely used in UK construction, there isn’t.
All it says is that the works are complete, “except for minor defects which do not prevent the building from being used for its intended purpose.”
Sounds simple — but what counts as “minor”? And who decides?
That’s where things get messy.
Because Practical Completion isn’t a science. It’s a judgement call. And the person making that call is the contract administrator — often the architect, employer’s agent, or sometimes even the employer themselves.
The Grey Zone of “Minor Defects”
Here’s where most of the arguments begin.
Some defects clearly qualify as minor:
• A scuffed wall? Probably fine.
• Loose door handles? Manageable.
But others cross the line:
• Missing handrails? Definitely not.
• Un-commissioned fire alarms? No chance.
The tricky part is that there’s no universal rulebook. What’s minor on one project might be major on another.
That’s why the contract administrator’s professional judgement is so crucial. They decide when the building is usable, safe, and ready — even if a few minor snags remain.
Why Practical Completion Matters So Much
It’s not just a ceremonial “we’re done” moment.
Certifying Practical Completion triggers a chain of major legal and financial events:
1. Liquidated damages stop.
No more daily penalties for the contractor running behind schedule.
2. Risk and responsibility shift.
Once certified, the client takes on insurance, damage, and maintenance obligations.
3. Retention is released.
Usually, half of the retained money is paid to the contractor.
4. The Defects Liability Period begins.
Typically lasting 6–12 months, this is when remaining defects must be fixed — but the building can already be used.
Get it right, and the project closes smoothly.
Get it wrong, and disputes start flying.
Where Projects Go Wrong
Because Practical Completion is open to interpretation, it often becomes a battleground.
• Contractors push for early certification to stop damages and trigger payment.
• Employers or administrators delay certification to ensure the work is truly finished.
Move too fast, and you might accept incomplete work.
Wait too long, and you could unfairly penalise a contractor.
It’s a tightrope walk that demands clarity, communication, and careful record keeping.
How to Handle Practical Completion the Right Way
At Harrison Clarke, we advise clients and contractors alike to make Practical Completion a defined, documented process — not a last-minute argument.
Here’s how to do it right:
1. Set Expectations Early
Before signing the contract, agree on what Practical Completion will look like.
Define clear benchmarks. Document them. Make sure everyone — contractor, client, and contract administrator — shares the same picture of “done”.
2. Start Snagging Early
Don’t leave the snagging list until the handover day.
Keep a rolling list during construction so issues are logged, categorised, and resolved progressively.
It avoids panic at the end and shows you’re managing quality throughout.
3. Focus on Usability, Not Perfection
Buildings are like people — never flawless.
The real question is: can it be used safely and effectively?
If yes, then you’re probably close to completion.
4. Get Advice Before Certifying
If there’s uncertainty, pause.
Certifying too early can expose you to risk, especially if key safety or regulatory items aren’t finished.
Speak to a professional before signing anything off — the cost of good advice is always less than the cost of a dispute.
The “Trifling Defects” Test — A Landmark Case
A 2019 Court of Appeal case — Mears Ltd v Costplan Services (South East) Ltd — clarified one of the biggest questions around Practical Completion: how much imperfection is acceptable?
In that case, 56 student flats were built about 3% smaller than planned. Mears argued that this was a breach of contract and refused certification.
But the court disagreed.
They ruled that a “trifling defect” — even one that technically breaches the contract — doesn’t stop Practical Completion.
The logic?
If a defect is small enough not to matter in the real world, it shouldn’t delay certification.
That decision reshaped how administrators assess Practical Completion.
It doesn’t mean ignoring defects — they still need to be recorded and rectified during the Defects Liability Period — but it means being reasonable and practical.
Avoiding Disputes and Delays
Most Practical Completion arguments come from poor communication, not bad workmanship.
To prevent disputes:
• Define completion standards before work begins.
• Keep inspection records and photo evidence.
• Update snagging lists regularly.
• Confirm agreements in writing after site meetings.
Clarity is your best protection — especially when payments, warranties, and deadlines all depend on one person’s judgement.
For another real-world example of project risk and prevention, see our article on Why Get Professional Advice Before Starting Building Work.
How Professionals Manage It
On projects managed by Harrison Clarke, we make Practical Completion an objective, not an argument.
We:
• Define what success looks like before works start
• Distinguish clearly between major and minor defects
• Hold open snagging sessions near the end of the build
• Always ask: Is the building ready to be used safely and effectively?
If the answer’s yes — and every remaining issue is recorded and agreed — that’s Practical Completion done properly.
The Bottom Line
Practical Completion isn’t about perfection.
It’s about readiness — the point where a building can safely serve its purpose, even if a few finishing touches remain.
But it’s also not something to rush. Once it’s certified, the clock starts ticking on liability, payment, and risk. Get it wrong, and there’s no easy rewind.
Whether you’re a client, contractor, or project manager, treat Practical Completion with care and clarity. It’s not just a signature — it’s the line between building and owning, between liability and handover.
And if you’re unsure what’s “minor”, “major”, or “trifling”, speak to a professional first. At Harrison Clarke Chartered Building Surveyors, we help clients navigate this crucial stage safely, fairly, and confidently. If you need help with Practical Completion, you can contact our friendly team on 02381 550051.
For more expert advice on surveying and property matters, check out our range of informative videos on our website or YouTube channel. Harrison Clarke Chartered Surveyors is here to guide you every step of the way!
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