An essential component to any project, construction specifications are written communication of the design intent to fulfill specific project requirements. While drawings and plans communicate where to install, specifications tell a contractor what and how to complete the job.
Construction specifications are an ultimate source of quality assurance for a construction project, and it’s vital for everyone across the building lifecycle to understand how they’re built and how to use them.
Inputs to a Construction Specification
Well-written construction specifications capture a wide range of critical information for a project. Inputs to the specs may include what type of equipment can be used onsite, the techniques necessary for the build, material requirements and acceptable deviations, best practices for trades, certifications, testing standards, and potentially the recommended temperature range for the work (concrete).
Depending on the structure of the project, input for specifications may come from the project owner, from the designer/architect, from engineering teams or from any combination of the above. In progressive Design-Build projects, input to the specifications may even come from the general contractor.
All of the input and the requirements need to be clearly articulated in the construction specifications from the beginning of the project; not only are the specifications vital to properly estimate the work and procure materials, but well-defined specifications also help minimize disputes later in the project during the procurement and construction phases of the project.
Structure of a Good Specification
Construction specifications are primarily organized as 3-Part Specs, meaning that for each section, there are three common components that govern the project: General, Products and Execution.
Part 1 – General
Requirements in Part 1 supplement the “General Requirements” of Division 01 sections by setting particular requirements about the materials and workmanship included in each section. For example, in the case of mechanical insulation, it sets requirements for submittals, quality control and other administrative elements that are unique to mechanical insulation.
Part 2 – Products
Requirements in Part 2 contain provisions that set the quality requirements for products used in the section by describing materials, products, equipment and manufacturing tolerances or factory testing requirements where applicable. It is crucial to review these sections carefully during procurement workflows, as the project owner will use this space to communicate specific manufacturer/model requirements for materials.
Part 3 – Execution
Requirements in Part 3 specify how the products described in Part 2 should be incorporated into the work. This space also specifies workmanship requirements and field quality-control testing requirements. Note however that Part 3 of specs does not dictate the contractor’s means and methods except where they may conflict with requirements established in the specification.
Organization of Construction Specifications
Well-written construction specifications must be organized in a logical format to make navigation of the requirements easy for both owners and contractors. In the United States, most specifications are organized by MasterFormat (Trade/Work-derived) or Uniformat (system-derived). In other regions, specifications may be organized through other standards such as Uniclass or Omniclass (lifecycle-derived).
MasterFormat’s organizational structure does not imply how the work specified in a project manual is to be assigned to various design disciplines, trades, or subcontractors. That work is left to the general contractor or design lead to work out with consultants and trade contractors using scope of work or similar documents. Trades are likely to be responsible for subjects from multiple Divisions, as well as from multiple Subgroups. Local practice or regulation will also likely have an effect on how work is designed and performed.
There are many specification standards as well. The most referenced in North America comes from the Construction Specifications Institute (CSI). However, other commonly used standards like the Unified Facilities Guide Specifications (UFGS) or National Building Specification (NBS) are used frequently. Many owners, especially those with large institutional footprints, may have their own specifications customized to their specific needs.
The best way to get comfortable with construction specifications is to spend time reading and analyzing them. For more information on how to read construction specifications and the critical elements to watch for as an estimator, check out our breakdown here.
