Performance specified work in construction contracts
The phrase ‘performance specified work’ refers to aspects of a building development that are identified in contract documentation to be designed by contractors or suppliers.
Specifications vary considerably depending on the stage to which the design has been developed, ranging from performance (open) specifications that require further design by the contractor, to prescriptive (closed) specifications where the design is already complete when the project is tendered.
Most projects involve a combination of performance and prescriptive specifications. Items crucial to the design may be specified prescriptively (such as external cladding) whilst less critical items, or items requiring specialist design may be specified only by performance (such as service lifts).
Performance specifications describe the result that is required from particular items and leave it to the contractor or supplier to satisfy that requirement. In effect it requires them to complete the design. The nature of the performance required is typically defined by the desired outcome, or by reference to standards. See Performance specification for more information.
Performance specified work is increasingly common as buildings become more complex and the supply chain becomes more integrated, with contractors and suppliers having greater involvement in design at an earlier stage of the project.
Performance specified work used to be most commonly defined in a ‘contractors designed portion’ as a supplement to the main contract, but increasingly now it forms part of the requirements of the main contract itself.
Separate sub-contractor design agreements are available where the main contractor is to design specific parts of the works and a sub-contractor is to design part or all of sub-contract works.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Treasury responds to sector submission on Warm Homes
Trade associations call on Government to make good on manifesto pledge for the upgrading of 5 million homes.
From self-climbing robotic installations to metacores and PORT tech: A tour.
A dynamic brand built for impact stitched into BSRIA’s building fabric.
BS 9991:2024 and the recently published CLC advisory note
Fire safety in the design, management and use of residential buildings. Code of practice.
NBS launches industry guide for specification writing
Available for free and as immediate download.
Peter Barber’s work revives forgotten building types.
Insights of how to attract more young people to construction
Results from CIOB survey of 16-24 year olds and parents.
Focussing on the practical implementation of electrification.
Preston flood scheme completes primary school SuDS
Three primary schools benefit from SuDS schemes.
Sustainable Urban Drainage and Biodiversity
Awards for champions of these interconnected fields now open.
Microcosm of biodiversity in balconies and containers
Minor design adaptations for considerable biodiversity benefit.
CIOB student competitive construction challenge Ireland
Inspiring a new wave of Irish construction professionals.
Challenges of the net zero transition in Scotland
Skills shortage and ageing workforce hampering Scottish transition to net zero.
Private rental sector, living standards and fuel poverty
Report from the NRH in partnership with Impact on Urban Health.
.Cold chain condensing units market update
Tracking the evolution of commercial refrigeration unit markets.
Attending a conservation training course, personal account
The benefits of further learning for professsionals.
Restoring Alexander Pope's grotto
The only surviving part of his villa in Twickenham.
International Women's Day 8 March, 2025
Accelerating Action for For ALL Women and Girls: Rights. Equality. Empowerment.
Lack of construction careers advice threatens housing targets
CIOB warning on Government plans to accelerate housebuilding and development.
BSRIA market intelligence division key appointment
Lisa Wiltshire to lead rapidly growing Market Intelligence division.