Understanding Instruments of Service

By AIA Contract Documents

June 8, 2023

When it comes to the world of architecture and engineering, the creative process often relies on a wide array of tools and techniques. Among these essential elements, instruments of service play a pivotal role. These instruments, encompassing drawings, specifications, and other documents, serve as vital communication channels between designers, clients, and contractors. By conveying the essence of a project, they transform abstract ideas into tangible realities. In this article, we explore the significance of instruments of service and their indispensable role in the design and construction industry.

Understanding Instruments of Service

Instruments of service refer to the collection of documents, drawings, specifications, calculations, and other tangible materials produced by design professionals during the various stages of a project. They act as a medium for conveying the intent and technical details of a design. Architects, engineers, and other design professionals employ these instruments to communicate their vision to clients, obtain necessary permits, and guide contractors during construction.

Types of Instruments of Service

  • Drawings: Drawings are visual representations that illustrate the design intent, ranging from conceptual sketches to detailed construction drawings. They convey critical information about dimensions, materials, and spatial relationships. Drawings can include floor plans, elevations, sections, and details, providing a comprehensive overview of the project.
  • Specifications: Specifications complement drawings by providing written descriptions of materials, products, and construction techniques. They outline the quality standards, installation methods, and performance requirements expected for each component of the project. Specifications ensure that contractors understand the project’s technical aspects and execute the design accordingly.
  • Calculations: Complex projects often require extensive calculations to determine load capacities, structural integrity, energy performance, and other technical parameters. Calculations serve as a foundation for decision-making, validating the feasibility and safety of a design. They are essential in ensuring compliance with regulatory codes and standards.

Importance and Functionality

Instruments of service serve several crucial functions in the design and construction industry:

  • Communication: They act as a universal language, allowing designers to effectively communicate their ideas to clients, consultants, and contractors. Precise drawings and specifications leave little room for ambiguity, ensuring a shared understanding of the project’s scope and requirements.
  • Legal and Professional Compliance: Instruments of service establish a contractual framework between design professionals and their clients. They provide evidence of professional services rendered and establish the basis for legal protection. Moreover, adherence to industry standards and building codes ensures compliance with regulations, ensuring the safety and legality of the project.
  • Construction Guidance: Contractors rely on instruments of service to execute the design accurately. Detailed drawings and specifications guide the construction process, ensuring that the project is implemented in accordance with the intended vision. They serve as a reference point, reducing errors, conflicts, and potential delays during construction.
  • Documentation and Maintenance: Instruments of service contribute to the documentation of the project, recording its evolution from concept to completion. They become valuable resources for future maintenance, renovations, or additions, enabling efficient decision-making and ensuring the project’s longevity.


Instruments of service form the backbone of architectural and engineering practice, allowing designers to articulate their vision and bring it to life. These indispensable tools, including drawings, specifications, and calculations, facilitate effective communication, legal compliance, and accurate construction execution. By understanding and appreciating the significance of instruments of service, design professionals can enhance their ability to create remarkable built environments that stand the test of time.

AIA Contract Documents has provided this article for general informational purposes only. The information provided is not legal opinion or legal advice and does not create an attorney-client relationship of any kind. This article is also not intended to provide guidance as to how project parties should interpret their specific contracts or resolve contract disputes, as those decisions will need to be made in consultation with legal counsel, insurance counsel, and other professionals, and based upon a multitude of factors.