- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 20 Jul 2020
The design life (or design service life) of a building, other structure or component, is the period of use as intended by the designer after which it may need to be replaced. Before this period has elapsed, it should remain fit for purpose.
Design life will vary according to the type and use of the element being considered. BS EN 1990, Eurocode - Basis of structural design, (Eurocode 0) gives indicative design lives for various types of structure:
- Category 1: Temporary structures, not including structures or parts of structures that can be dismantled with a view to being re-used – 10 years.
- Category 2: Replaceable structural parts, e.g. gantry girders, bearings – 10 to 25 years.
- Category 3: Agricultural and similar buildings – 15 to 30 years.
- Category 4: Building structures and other common structures – 50 years.
- Category 5: Monumental building structures, bridges and other civil engineering structures – 100 years.
- Moisture, humidity and rain.
- Temperature and temperature fluctuations.
- Solar radiation.
There is no legally agreed definition of design life (in fact, there is not even a legally agreed definition of 'design'), so if it is to be included in contract documentation as a performance requirement, it is important that it is carefully defined within the contract documents and that it is consistent with all other requirements in the contract documents.
 Related articles on Designing Buildings Wiki
- Concept structural design of buildings.
- Design quality for buildings.
- Economic life.
- End of life potential.
- Fitness for purpose.
- Functional life.
- Life cycle.
- Life cycle assessment.
- Permanent structure.
- Re-evaluating the design life of buildings.
- Required life.
- Service life.
- Structures at the end of their design life.
- Technical life.
- Temporary structure.
- Utilising life cycle costing and life cycle assessment.
- Whole-life costs.
- Whole-life value.
Featured articles and news
The importance of emergency planning.
Eight forms of resource optimisation.
CIOB responds to Chancellor Sunak's announcement on jobs and the economy.
Revised guide to competition rules available.
Brick slip soffit systems and intricate brick features.
An innovative engineering approach could have had tragic consequence for NYC.
Some secrets behind how canals work.
Breaking down possible steps of pre-contract management.
ICE event includes comments from Welsh Government Minister Julie James.
How to write them and what they should include.
Designing Buildings Wiki becomes the world's first website to adopt the new knowledge standard.
Assessing the most beneficial design elements.