Time extensions in construction contracts
Construction contracts generally allow the construction period to be extended where there is a delay that is not the contractor's fault. In the United States, this is described as a time extension. The UK equivalent is an extension of time (EOT).
When it becomes reasonably apparent that there is, or that there is likely to be, a delay that could merit a time extension, the contractor gives written notice to the contract administrator identifying the relevant event that has caused the delay. Time extensions are granted based on the contractor being able to demonstrate that the delay was caused by events beyond their control. The contract guidelines typically specify the provision of time extension requests.
There are various circumstances in which time extension requests will be valid, including:
- Delays are caused by the owner changing the design.
- A delayed start to the works by request of the owner.
- Site conditions (e.g. sub-surface conditions) that differ from the project plans.
- Exceptionally adverse weather.
- Variations to the original scope or contract required by the owner.
- Force majeure.
- Legal issues that affect project completion or the contractor’s performance.
- The supply of materials and goods by the owner.
There are various circumstances in which time extension requests will be deemed invalid, including:
- Delays are caused by subcontractors.
- When the workforce is insufficient.
- The contractor underperforms, i.e. by procuring long-lead items.
- Delays caused by normal adverse weather conditions.
- Where there is inadequate evidence that irrecoverable delays have not been caused by the contractor.
In order for a time extension to be granted it is important that the contractor is transparent and communicative in their dealings with the owner and the project team. The project manager must be informed at the earliest opportunity and, if they deem it valid, they will submit a formal time extension request. For further information, see What should be included in a time extension request?
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
What they are, how they work and why they are popular in many countries.
Plastic, recycling and its symbol
Student competition winning, M.C.Esher inspired Möbius strip design symbolising continuity within a finite entity.
Do you take the lead in a circular construction economy?
Help us develop and expand this wiki as a resource for academia and industry alike.
Warm Homes Plan Workforce Taskforce
Risks of undermining UK’s energy transition due to lack of electrotechnical industry representation, says ECA.
Cost Optimal Domestic Electrification CODE
Modelling retrofits only on costs that directly impact the consumer: upfront cost of equipment, energy costs and maintenance costs.
The Warm Homes Plan details released
What's new and what is not, with industry reactions.
Could AI and VR cause an increase the value of heritage?
The Orange book: 2026 Amendment 4 to BS 7671:2018
ECA welcomes IET and BSI content sign off.
How neural technologies could transform the design future
Enhancing legacy parametric engines, offering novel ways to explore solutions and generate geometry.
Key AI related terms to be aware of
With explanations from the UK government and other bodies.
From QS to further education teacher
Applying real world skills with the next generation.
A guide on how children can use LEGO to mirror real engineering processes.
Data infrastructure for next-generation materials science
Research Data Express to automate data processing and create AI-ready datasets for materials research.
Wired for the Future with ECA; powering skills and progress
ECA South Wales Business Day 2025, a day to remember.
AI for the conservation professional
A level of sophistication previously reserved for science fiction.
Biomass harvested in cycles of less than ten years.
An interview with the new CIAT President
Usman Yaqub BSc (Hons) PCIAT MFPWS.
Cost benefit model report of building safety regime in Wales
Proposed policy option costs for design and construction stage of the new building safety regime in Wales.
Do you receive our free biweekly newsletter?
If not you can sign up to receive it in your mailbox here.

























