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
Call for greater recognition of professional standards
Chartered bodies representing more than 1.5 million individuals have written to the UK Government.
Cutting carbon, cost and risk in estate management
Lessons from Cardiff Met’s “Halve the Half” initiative.
Inspiring the next generation to fulfil an electrified future
Technical Manager at ECA on the importance of engagement between industry and education.
Repairing historic stone and slate roofs
The need for a code of practice and technical advice note.
Environmental compliance; a checklist for 2026
Legislative changes, policy shifts, phased rollouts, and compliance updates to be aware of.
UKCW London to tackle sector’s most pressing issues
AI and skills development, ecology and the environment, policy and planning and more.
Managing building safety risks
Across an existing residential portfolio; a client's perspective.
ECA support for Gate Safe’s Safe School Gates Campaign.
Core construction skills explained
Preparing for a career in construction.
Retrofitting for resilience with the Leicester Resilience Hub
Community-serving facilities, enhanced as support and essential services for climate-related disruptions.
Some of the articles relating to water, here to browse. Any missing?
Recognisable Gothic characters, designed to dramatically spout water away from buildings.
A case study and a warning to would-be developers
Creating four dwellings... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.






















