Vitiate
To vitiate is the act of impairing or voiding the effect of something else. In terms of buildings and construction this may be an action, failure of an action or a factor that has the potential to invalidate a contract or specific element of a contract or agreement tis making it void. For example through fraud, misrepresentation, legal capacity and so on.
For example if an insured person fails to disclose relevant material facts or misrepresents a case to an an insurer before the insurance policy is issued it may vitiate the policy, thus making it invalid. If a landlord does of fails to do something to a property that is likely to make a tenant's insurance policy void, the landlord may be liable for reparation costs.
In the case of a force majeure event, it may be ground for and excuse non-performance in a contract, but only for the duration of the event, it does not necessarily void or vitiate the contract in its entirety.
In a construction project variations to a contract, that are agreed upon, may be requested under the correct procedure, variations do not vitiate a contract. The original contract remains in tact and in place, it merely has been adjusted, a vitiated contract is one that is no longer valid and is thus void.
[edit] Related articles on Designing Buildings
- Abortive work in building design and construction.
- Architect's instruction.
- Change control procedure for building design and construction.
- Change order for construction contracts.
- Compensation event.
- Confirmation of verbal instruction.
- Contract sum.
- Extension of time EOT in construction contracts.
- How to prepare a claim for an extension of time.
- Loss and expense.
- Payment for extra work.
- Prime cost sum.
- Provisional sum.
- Relevant event.
- Relevant matter.
- Scope of work.
- Valuation of interim payments.
- Variations in construction contracts.
Featured articles and news
Welsh and Scottish 2026 elections
Manifestos for the built environment for upcoming same May day elections.
Advancing BIM education with a competency framework
“We don’t need people who can just draw in 3D. We need people who can think in data.”
Guidance notes to prepare for April ERA changes
From the Electrical Contractors' Association Employee Relations team.
Significant changes to be seen from the new ERA in 2026 and 2027, starting on 6 April 2026.
First aid in the modern workplace with St John Ambulance.
Ireland's National Residential Retrofit Plan
Staged initiatives introduced step by step.
Solar panels, pitched roofs and risk of fire spread
60% increase in solar panel fires prompts tests and installation warnings.
Modernising heat networks with Heat interface unit
Why HIUs hold the key to efficiency upgrades.
Reflecting on the work of the CIOB Academy
Looking back on 2025 and where it's going next.
Procurement in construction: Knowledge hub
Brief, overview, key articles and over 1000 more covering procurement.
Sir John Betjeman’s love of Victorian church architecture.
Exchange for Change for UK deposit return scheme
The UK Deposit Management Organisation established to deliver Deposit Return Scheme unveils trading name.
A guide to integrating heat pumps
As the Future Homes Standard approaches Future Homes Hub publishes hints and tips for Architects and Architectural Technologists.
BSR as a standalone body; statements, key roles, context
Statements from key figures in key and changing roles.
Resident engagement as the key to successful retrofits
Retrofit is about people, not just buildings, from early starts to beyond handover.




















