Construction activities
An activity is an operation or process consuming time and possibly other resources. An individual or work team can manage an activity. It is a measurable element of the total project programme.
The term ‘duration’ refers to the length of time needed to complete an activity.
The term 'path' refers to an activity or an unbroken sequence of activities in a project network. The critical path is the longest sequence of activities through a project network from start to finish, the sum of whose durations determines the overall project duration.
‘Float’ is the time available for an activity in addition to its planned duration. For more information see: Programme float.
‘Free float’ is the amount of time that an activity can be delayed beyond its early start/early finish dates without delaying the early start or early finish of any immediately following activity.
A hanging activity is an activity not linked to any preceding or successor activities.
'Impact' is the effect a change has on an activity or the effect a change to one activity has
on another activity.
Ref Society of Construction Law Delay and Disruption Protocol, 2nd edition, February 2017, published by the Society of Construction Law (UK). https://www.scl.org.uk/resources/delay-disruption-protocol
Earned Value Management Handbook, Published by the Association for Project Management in March 2013 suggests that: ‘…Each work package comprises a number of activities to be performed. Each activity can be assigned to only a single work package. Each activity is a stepping stone towards completion of its parent work package.’
NB The CIOB Planning Protocol 2021 (CIOB PP21), a technical information sheet published by the Chartered Institute of Building (CIOB) in February 2021, defines an activity as: ‘A definable and measurable unit of work. Each activity has a start date, an end date and a duration.’
The glossary of statistical terms, published by the Organisation for Economic Co-operation and Development (OECD), states: ‘An activity is a process, i.e. the combination of actions that result in a certain set of products.’
[edit] Related articles on Designing Buildings
Featured articles and news
Buildings that changed the future of architecture. Book review.
The Sustainability Pathfinder© Handbook
Built environment agency launches free Pathfinder© tool to help businesses progress sustainability strategies.
Government outcome to the late payment consultation, ECA reacts.
IHBC 2025 Gus Astley Student Award winners
Work on the role of hewing in UK historic conservation a win for Jack Parker of Oxford Brookes University.
Future Homes Building Standards and plug-in solar
Parts F and L amendments, the availability of solar panels and industry responses.
How later living housing can help solve the housing crisis
Unlocking homes, unlocking lives.
Preparing safety case reports for HRBs under the BSA
A new practical guide to preparing structural inputs for safety cases and safety case reports published by IStructE.
Male construction workers and prostate cancer
CIOB and Prostate Cancer UK encourage awareness of prostate cancer risks, and what to do about it.
The changed R&D tax landscape for Architects
Specialist gives a recap on tax changes for Research and Development, via the ACA newsletter.
Structured product data as a competitive advantage
NBS explain why accessible product data that works across digital systems is key.
Welsh retrofit workforce assessment
Welsh Government report confirms Wales faces major electrical skills shortage, warns ECA.
A now architectural practice looks back at its concept project for a sustainable oceanic settlement 25 years on.
Copyright and Artificial Intelligence
Government report and back track on copyright opt out for AI training but no clear preferred alternative as yet.
Embedding AI tools into architectural education
Beyond the render: LMU share how student led research is shaping the future of visualisation workflows.
Why document control still fails UK construction projects
A Chartered Quantity Surveyor explains what needs to change and how.
Inspiration for a new 2026 wave of Irish construction professionals.
New planning reforms and Warm Homes Bill
Take centre stage at UK Construction Week London.























