The Leadership in Energy and Environmental Design (LEED) Green Building Rating System is now being applied to many new and major retrofit construction projects throughout Canada. The LEED Certification process is administered by the Canada Green Building Council (CaGBC). LEED provides a benchmark for the design, construction and operation of high performance green buildings, and promotes a whole-building approach to sustainability by recognizing performance in five key areas: (1) sustainable site development; (2) water efficiency; (3) energy efficiency; (4) materials selection; and (5) indoor environmental quality.
LEED Certification is based on the total point score achieved, following an independent review and an audit of selected Credits. There are four levels of certification: Certified, Silver, Gold, and Platinum. The list of buildings that have achieved LEED Certification, or are working towards certification, is growing monthly and includes a wide range of institutional, commercial, and residential projects. A variety of recent LEED projects are highlighted on the CaGBC website at <www.cagbc.org>.

A SMACNA Guideline plays a key role in obtaining one of the Environmental Quality (EQ) Credits for new construction and major retrofits under LEED Canada NC-1.0, and also for tenant improvements within new or existing spaces, under LEED Canada CI-1.0.

EQ Credit 3.1 is titled Construction IAQ Management Plan: During Construction and is intended to prevent indoor air quality (IAQ) problems resulting from the construction process. The LEED documentation for EQ 3.1 specifically identifies the application of the SMACNA IAQ Guideline for Occupied Buildings Under Construction as the key element in achieving this credit. The current LEED documentation refers to the first edition of the SMACNA IAQ Guideline, published in 1995. However, a second edition of the Guideline was subsequently released in 2007.

Chapter three in the SMACNA IAQ Guideline describes a series of control measures  to help minimize contamination of a building from construction activities. These include HVAC System Protection, Source Control, Pathway Interruption, Housekeeping, and Scheduling.

HVAC Protection's primary goal is to prevent construction debris from entering the ductwork and spaces. To achieve this, the return side of the HVAC system should be isolated during heavy construction or demolition. At times when the HVAC system has to be operated during construction, temporary filters should be installed, and replaced just prior to occupancy.

Source Control is achieved through the selection of low emission materials and finishes including paints, sealants, adhesives, carpeting, other furnishings, and cleaning products. There is an ever increasing number of low-emission products available in the construction industry. Important note: Christopher Collett and Associates Ltd. has conducted IAQ testing in LEED projects throughout BC and has found that the impact of solvent-based finishing and cleaning products is often a forgotten element in IAQ Management.

Pathway Interruption is an important strategy to prevent the migration of contaminants through a building during construction. Approaches can include ventilation using 100 outside air during installation of Volatile Organic Compound (VOC) emitting materials, and erecting physical barriers between work areas and non-work areas.

Housekeeping should be standard practice in all projects, with frequent cleaning to remove construction dust and debris, immediate clean-up of any spills, removal of accumulated water, and other actions to keep work areas dry to prevent the potential for the growth of microbial contaminants.
Careful Scheduling of the sequence of construction can minimize the absorption of VOCs by other building materials that can act as “sinks”  For example, paints, sealants, and other volatile materials should be applied and allowed to dry before ceiling tile and carpets are installed.

While the SMACNA IAQ Guideline provides the framework to achieve LEED EQ Credit 3.1,  successful application of the credit requires clear documentation of the IAQ Management Plan, and effective communication of the practical management procedures to the trades working throughout the construction process. In successful projects, on-going review of these construction related IAQ issues is included as part of the regular commissioning meetings.
The current SMACNA IAQ Guideline for Occupied Buildings Under Construction is available for purchase on the SMACNA website at <www.smacna.org/bookstore>.

SMJ