15 September 2023 | by Last amended on 02 October 2023

Integrating a golden thread of information into construction specifications is vital for meeting Building Safety Act 2022 requirements, making taking the time and effort to create robust, thorough and detailed specifications more critical than ever: providing a structured and detailed framework for conveying essential information about materials, methods, standards and quality requirements and ensuring clarity, compliance, accountability, and consistency throughout the construction project.

At its core, specification ensures the efficient and straightforward exchange of information between the client, designer and contractor. Through specification, you use words to describe things that can’t be visualized or explained via a drawing or model:

  • Scope of work
  • Contract type
  • Site conditions
  • Asset performance requirements
  • Applicable standards
  • Installation process
  • Systems and products
  • Quality of work

Types of specification

We use three primary types of specifications in construction.

  • Prescriptive
  • Performance
  • Proprietary


Prescriptive specifications provide details regarding what materials to use and how they should be installed, including:

  • General information like applied quality standards, design requirements, quality control elements and how to handle products.
  • Product-specific details that cover what products to use for each task and their required performance levels.
  • Execution requirements addressing materials' preparation and installation, including quality testing procedures.


Performance specifications cover a project’s operational requirements and how a product should behave once installed. Performance specs generally entail significant testing to ensure the project is within stipulated operational parameters.


Proprietary specifications are used when a specifier wants to include a specific product range or type. Examples of projects that might require proprietary specifications include conservation and renovation projects with a need to match or integrate with existing materials and equipment.

What specification brings to a project

Taking time to develop a robust specification ensures a better understanding of a project’s requirements. Having clear information upfront means the process is more efficient and effective. That, in turn, translates to time, effort and cost savings.

15 essential reasons to use specification and 10 desirable outcomes

Through specification, you can:

  1. Provide clear instructions on project intent, performance and construction expectations.
  2. Clarify what standards and quality should be applied.
  3. Define the materials and manufacturers’ products to be used.
  4. Identify installation, testing and handover requirements.
  5. Use classification to support asset handover and running.
  6. Avoid overloading drawings and models with detailed information that can be difficult to identify.
  7. Support project costing – including materials, products, performance and workmanship.
  8. Minimise risk and create additional support for potential legal disputes by having specifications and drawings as part of your contractual documents.
  9. Validate client brief interpretation and assure the client that the asset commissioned is the one delivered.
  10. Save time and money by proactively addressing onsite construction questions through the clear, concise and thorough provision of information.

Additionally, the specification:

  1. Is not only essential for the construction phase but can be used during soft landing and as part of the asset management and lifecycle plan.
  2. Creates a living document that the project team can and should use throughout the construction phase.
  3. Can also be used for the project audit trail and should form part of the handover documents, thus forming the basis for how the asset management team runs the asset.

By creating a suite of office masters, a team can:

  1. Improve efficiency, provide quality assurance and ensure project consistency.
  2. Save time and money across projects. Office masters can draw on specialist knowledge and be adapted to suit individual project specifics.

10 desirable outcomes:

  1. Creates a clear project definition.
  2. Provides straightforward instructions on how to achieve the desired result.
  3. Supports your drawings.
  4. Enables more accurate pricing.
  5. Minimises risk.
  6. Improves compliance and avoids legal problems.
  7. Provides legally binding documentation.
  8. Saves time and money.
  9. Assures the client that you’re delivering what they asked for.
  10. Delivers an essential resource for asset management and maintenance.

Specification, the golden thread and ensuring compliance with The Building Safety Act

The golden thread (of information) is a shorthand term used to describe digitally held building data that is accurate, up-to-date and accessible to everyone concerned. It is the method by which the Building Safety Act 2022 places legal responsibility upon duty holders to ensure and enforce transparency and accountability regarding the safety of the buildings we use.

Since its introduction in 2020 by The Building Regulations Advisory Committee’s Golden Thread Report and its subsequent inclusion in The Building Safety Act 2022, the golden thread of information in construction has been accepted as our industry’s way forward, capturing the digital fingerprints of the people involved, recording decisions made and creating transparency through a clear accountability trail.

While the Building Safety Act serves to enforce the golden thread, it is through robust specification that we can provide a practical, valuable and lasting way to ensure compliance.

  • Ensuring regulations compliance by providing information on the required safety standards, building codes and regulations to be adhered to.
  • Providing clarity and consistency about the methods and materials to be used during the construction process.
  • Promoting quality assurance efforts by defining the standards and expectations around materials and workmanship.
  • Supporting materials selection by providing details about the type, grade, and source of materials, which, in turn, can significantly impact an asset’s long-term performance and durability.
  • Defining the performance criteria needed to achieve desired outcomes, allowing for innovation and flexibility in meeting project objectives while ensuring safety and quality requirements are met.
  • Creating accountability by establishing a clear baseline for what is expected regarding materials and workmanship, thus holding contractors, subcontractors, and suppliers accountable for meeting the specified requirements.
  • Aiding in change management through information that can be updated and revised as the project progresses and/or design changes occur. Keeping your specifications up to date ensures that any changes in materials or methods are documented and communicated to all stakeholders, thus maintaining the integrity of the golden thread.
  • Playing a vital role in cradle-to-grave project documentation. Specifications are living documents to be referenced throughout the project's life cycle – from design and construction through maintenance, renovation and repurposing to end-of-life.

Through specification, we create a durable source of truth, weaving a golden thread of information through our construction projects and providing information that is accurate, understandable, consistent, accessible and valuable over time.

When should you start writing?

The short answer is as early in the project lifecycle as possible. A project specification is a living document, and by creating it early on, you are allowing the specification to evolve and develop through the project timeline, thus providing vital information from project start through handover and asset management.

Early stage specification:

  • Is useful when meeting with a client to help clarify what they want to achieve on their project.
  • Aids in understanding project performance requirements.
  • Is helpful when discussing complexes, entities, spaces, locations, elements, systems and products.
  • Provide essential information that can be incorporated into the Employer’s Information Requirements (EIR).

As construction embraces the digital age, project data requirements become more complex. Having a core, unified basis of information is tantamount to project success. Specifications are crucial in creating that basis, clearly representing the built asset and providing vital information to owners, facilities managers and maintenance teams to optimize use, reuse and end-of-life activities.

More about NBS

NBS Chorus

In the article Using NBS to specify sustainable outcomes on projects, NBS explores how the Plan of Work and NBS Chorus can be used to tailor a project to meet sustainability expectations across the project timeline. Due to its flexible, cloud-based functionality, you can access your specifications through Chorus across locations and organizations. There is no software to install and no fuss – just access to your specs anywhere, anytime, and on any device. All that is required is a modern web browser and an internet connection.

Chorus allows you to specify by performance or prescriptively with generic or proprietary references. Clauses are editable and supported by technical guidance. It's available with different access levels, providing a solution for most budgets, from NBS Chorus Small Works for smaller practices to Chorus Pro Solution for those working on more complex projects. For more information, check out the hyperlinks or drop one of our team a note at info@thenbs.com.

NBS Source

NBS Source is a single source for product information that seamlessly integrates into a project's workflow and provides an additional level of enhanced product data in a consistent, structured format. It hosts thousands of construction materials, products and systems from manufacturers. These listings also link directly to NBS Chorus, providing a seamless way of 'Adding to Spec' in your projects.

NBS is continually pushing for more sustainability information in all manufacturer listings. The requested information includes aspects such as embodied carbon, country of manufacture and country of material origin, recycled content and end-of-life data. We are also seeing a rise in manufacturers providing Enhanced Product Declarations (EPDs), which can be accessed in the third-party certificates section.

If you are a specifier, you can view NBS Source here. Alternatively, if there are products you would like to see but occasionally cannot find within the platform, please drop us a note via manufacturers@thenbs.com with the details, and our team will reach out to the manufacturer on your behalf.

The Construction Information Service (CIS)

CIS is a comprehensive online collection of industry-relevant publications from around 500 publishers. NBS users with a CIS subscription can use embedded links across specifications platforms to access research and reference documents. The content is fully searchable, intelligently classified and continuously updated, and a generous amount of sustainability content can be searched and referenced.