Indoor Environmental Quality (IEQ)

Indoor Environmental Quality address concerns relating to indoor air quality, occupant’s health, safety, and comfort, air change effectiveness, and air contaminant management. The IEQ credit category seeks improvements to ventilation, indoor CO2 levels, daylighting, lighting quality, and thermal comfort—all of which have the potential to impact occupant health and performance.

Adhesives and Air Quality

While it is easy to think about the things we see in a building and how they affect air quality, there are also many products or materials that we don’t readily see in a finished space that are important, too. LEED certification seeks that all materials, including those not seen, address their chemical make-up and their potential impact on human health by limiting or eliminating such things as volatile organic compounds (VOCs). One such unseen but prevalent product is adhesives, which can be used throughout a school building to secure many products in place.

By way of example, let’s look at wood flooring that may be used in a gymnasium or perhaps be existing in a school. If the wood is placed over concrete, then an appropriate underlayment and adhesive may be the best way to install it. The selection process for the adhesive must address not only a long-lasting, durable bond, but also the ability to stand up to heavy foot traffic. There may be other considerations, too, such as moisture protection from the concrete and sound mitigation from footsteps on the floor.

At least one manufacturer has recognized the variety of needs and combines high-strength adhesive, moisture barrier, and sound abatement underlayment all in one low-VOC product. The goal is to provide a safe installation so parents, teachers, and students don’t have to worry about a school’s gymnasium flooring de-bonding from its substrate, possibly causing safety hazards to students walking, running, or exercising on top of it. A concurrent goal is to maintain good indoor air quality in the space through low-VOC content. Going further, the adhesive not only firmly grips wood flooring to the substrate, it protects the floor from damaging moisture vapor, which could cause deterioration, leveling problems, fissures, and even mold, which could be harmful to those using it day-to-day.

According to Ron Winterton, sales manager of Intermountain Wood Flooring, a major supplier to the architectural and design community in the Pacific Northwestern states, “Not only do all-in-one products like these offer excellent moisture protection, they provide sound abatement properties equivalent to ¼-inch cork underlayment.” He also recognizes the importance of manufacturer’s systems that help ensure the required thickness of the adhesive membrane is maintained, even if installers walk on the flooring before the adhesive has cured.

Photo courtesy of Bostik, Inc.

All-in-one wood floor adhesives are available in low-VOC formulations that also provide moisture protection, sound deadening, and mold protection.

CASE STUDY: FLOORING ADHESIVE IN A LARGE SCHOOL

Susan Heller of HY Floor and Gameline Painting Inc. was overseeing work on the renovation of a large school’s sports center. During the project, the company was asked to redo one of the adjacent rooms, which had been originally fitted with wood flooring but was recently damaged due to water intrusion. “There were 2 or 3 inches of water sitting on the wood floors, it was just unbelievable to look at,” said Heller. “Workers were able to get all the water off the floor, but it’s very hard to dry your slab, and in some places the moisture was still very high.”

According to Heller, the company was faced with a decision to either do the project with a separate moisture mitigation system, an option that would take more time than the tight deadline would allow, or to find another product to solve the problem. HY insisted on using an all-in-one adhesive state-of-the-art product, which provides moisture protection, sound deadening, crack isolation, and mold protection. It also incorporated a spacer system to ensure proper membrane thickness between the hardwood and substrate.

“The all-in-one system offers such good adhesion, plus, it’s easy to work with on both horizontal and vertical surfaces,” said Heller.

Photo courtesy of Bostik, Inc.

Daylight

The use of natural daylight in school buildings is not only desirable from a general indoor environment point of view, it has also been shown to positively improve the comfort, health, and learning abilities of students. Building designers often think first of glass to achieve daylighting goals, which is often appropriate, but glass block is another time-proven, durable option. Glass block can be used in both interior and exterior applications; it is inert, low maintenance, and highly durable. Glass block’s myriad of performance characteristics make it a superior choice for school construction by providing daylighting, security, sound control, and controllable levels of privacy. Plus, new glass block systems also can be a part of the building envelope to protect against outside forces all without giving up daylighting. New energy-efficient glass block can also provide improved insulation and solar heat gain values, which can meet or exceed energy conservation from other glazing options.

While glass blocks are traditionally specified in Division 4 masonry applications, there are new glass block systems that are engineered and prefabricated for use in Division 8 applications. These prefabricated high-performance systems have been tested to meet enhanced performance requirements and are resistant to hurricanes, tornadoes, blasts of force, and ballistic attacks. All of these systems also provide daylighting, privacy, and security, and contribute to LEED and sustainability. For interior applications, custom decorated glass blocks can complement the design of the school by providing subject specific décor to enhance the learning experience of students. Plus, they are easy to install, which improves efficiency by reducing labor at the job site.

Photos courtesy of PITTSBURGH CORNING

Glass block can be customized with messaging or artistic designs to enhance or complement the design of the building and classrooms. For example, a chemistry lab can have a glass block wall with the periodic table of elements on it. Clear or patterned glass block can also provide daylighting, while enhancing the learning atmosphere of the classroom.

CASE STUDY: DAYLIGHTING WITH GLASS BLOCK AT RIVER CREST ELEMENTARY SCHOOL

The River Crest Elementary School in Hudson, Wisconsin, featured glass block prominently and helped the building earn LEED Gold certification. At 93,450 square feet, River Crest Elementary School is Hudson’s sixth elementary school with a capacity for 588 students in grades kindergarten through fifth. Commissioned in 2006, this elementary school was to be a highly sustainable and innovative education center built to reflect the natural topography as it relates to its setting. With an environmental theme that reflected the school district’s vision of a sustainable learning environment, River Crest Elementary was created with healthful, daylit spaces, improved energy and water efficiency, and decreased operational costs while emphasizing environmental education.

Hoffman Planning, Design & Construction Inc., a total project management firm, made it its mission to achieve one of the school’s primary goals: becoming a sustainable model for the community. Catherine Cruickshank, senior project designer at Hoffman, was inspired to experiment by using glass blocks that were twisted and turned to create waves and ripples consistent with the River Crest theme, while achieving a balance between daylight and privacy. The glass blocks also enabled the elementary school to overcome the prerequisite challenge of acoustics to ensure classrooms are quiet enough for learning. With sustainability and privacy a guiding factor, Cruickshank added glass blocks to the guidance office, computer room and story area, and cafeteria. The glass block allowed natural light into the areas providing bright spaces that restrict noise and offer improved visual capability. “Initially, we were concerned about the acoustics in the guidance office, but the glass block worked out great,” said Cruickshank. “It let light into the space while providing privacy for conversations with students.”

Photos courtesy of PITTSBURGH CORNING

In the main foyer of the River Crest Elementary School, patterned glass blocks create waves, introducing light from the windows into the guidance office while still providing acoustical privacy.

Enhanced Acoustics

We have touched on the fact that LEED for Schools has both prerequisites and credit options for acoustical control in schools. The goal is: “To provide workspaces and classrooms that promote occupants’ well-being, productivity, and communications through effective acoustic design.” When looking to achieve that goal, architects often look at walls and floor/ceiling assemblies for things such as sound transmission class (STC) ratings. The means to achieve those ratings are fairly well known although some innovations continue to occur.

When looking at classroom walls designed for acoustics in schools, it is important to address the doors leading into those classrooms. Sound from a corridor may be thwarted by a wall assembly properly designed to mitigate sound transfer, but if the door is not also addressed, the end result will be poor. Since sound is energy and behaves the same way as other energy, this would be the equivalent of building a very energy-efficient exterior wall and then putting a very leaky window in it which would undo most of the effort put into the wall.

Fortunately, it is possible to specify doors and frame assemblies with high STC ratings. However, that is not where things end. The door, frame, and related door components all need to be looked at and addressed in order to achieve satisfactory results. To do so using individual products and components is theoretically possible, but functionally nearly impossible. The more direct solution is to specify complete door and window frame systems that are coordinated and independently tested for sound control. In this way, STC ratings are dependent on doors and frames being supplied as complete assemblies from a single manufacturer rather than separate doors, frames, seal systems, glazing, and hardware being supplied from different manufacturers. Typically, manufacturers of such complete systems can demonstrate acoustic performance as tested in accordance with ASTM E-330: Standard Test Method for Structural Performance of Exterior Windows, Doors, Skylights, and Curtain Walls by Uniform Static Air Pressure Difference, and ASTM E-413: Classification for Rating Sound Insulation.

Photo courtesy of AMBICO Limited

Specialized door, frame, and window systems can be specified to meet performance standards and still feature aesthetic qualities, such as this acoustic wood door and steel frame system achieving an STC rating of 51.

An additional consideration when looking at door and window frames is safety in regard to extreme weather. Many schools in certain areas of the country experience the threat of tornados giving rise to the need for tornado safe rooms. Frame door and hardware assemblies along with window frame and glazing assemblies on perimeter shelter walls need to be capable of resisting the forces imposed on it and protecting the critical life safety of the inhabitants. Such door and window assemblies are available and can be specified as tornado-resistant openings shown to be tested in accordance with FEMA 361 & 320 and ICC-500 standards.