Issue link: https://hi.iaq.net/i/248503
www.epa.gov/iaq/moisture Chapter 2: Designing for Moisture Control Introduction Designing Effective Moisture Controls The most common participants in the process of designing a building are architects, engineers, landscape architects and the clients. The design team can also include: Providing good moisture control in the design of a building is largely the responsibility of the design team. Third parties that provide construction management or commissioning services may play critical roles in the design and implementation of moisture controls. A construction management service may participate in the management of the project at varying levels from inception, design and construction to turnover and occupancy. The goal of construction management ordinarily is to manage the schedule, cost and quality to the owner's satisfaction, but if a construction manager is part of the design team, it is crucial that the manager take on responsibility for implementing the team's moisture control objectives. • The owner of the building, if the building is being designed and built for a specific person or entity. The owner can help identify how and by whom the building will be used. • The future occupants of the building, if they are known at the time the building is designed. They can help set goals for durability, maintainability and moisture protection. • Building and grounds personnel representing the owner, who can provide years of building operation and maintenance (O&M) experience. Building Commissioning • The contractor that will construct the building, if the contractor has been selected when the design work begins.13 Experienced contractors and subcontractors can bring the realities of managing moisture during construction to the design of the building. HVAC systems have been commissioned for many years by testing, adjusting and balancing (TAB). However, commissioning entire buildings is a relatively recent innovation in construction. In 1996, ASHRAE published The HVAC Commissioning Process Guideline 1-1996, which extended the scope of traditional TAB to include point-to-point testing of digital controls and functional performance testing to assess the performance of electrical and mechanical systems that work together. Since then this process has been extended to the electrical systems; potable, sanitary, drainage and irrigation systems; power production and cogeneration systems; the building enclosure; sustainable aspects of the project; and the entire building design process itself. In 2005, the U.S. General Services Administration (GSA) published The Building Commissioning Guide. The guide provides a process for including building commissioning in the planning, design, construction and post-construction phases of a project. A table in the guide summarizes commissioning activities and recommends the commissioning agent review the design for, among other things, the enclosure's thermal and moisture integrity and its moisture vapor Where there is a shortage of real estate for sale or rent, buildings are often designed and built on speculation. In such cases, the occupants, programs and processes that eventually will reside in the building are known only in general terms. For example, when planning an office building, the design team can assume the occupants will be ordinary office workers and the building will have no special sources of liquid water or humidity. However, the resulting design will not have the benefit of input from the owner, the actual occupants or the building and grounds staff that will have to make the building work over the years. Whether or not the contractor is on board during the design process, the contractor will have the important role of clarifying the design team's intentions regarding moisture control, planning measures to control water during construction, and preparing response plans for accidental water events that occur during construction. This role is explored in detail in Chapter 3. 13 26