CONTROLLING SOUND USING GYPSUM PANELS
Residents of multifamily buildings, whether condos, apartments, co-housing units, or other types, all have a fundamental need for some acoustic privacy. They really don’t want to hear their neighbors in an adjacent unit on either side, above, or below them and they certainly don’t want to feel like those neighbors can hear what they are saying or doing. Therefore, reducing the noise transfer from one living unit to another and between a living unit and a common area (hallways, community room, amenity spaces, etc.) can result in more satisfied owners and renters, less turnover, and fewer vacancies.
From a design perspective, achieving this common goal of acoustic privacy means calling for wall assemblies and floor/ceiling assemblies with adequate Sound Transmission Class (STC) and Impact Insulation Class (IIC) ratings. The higher the STC or IIC rating for a particular assembly, the less sound that is transferred between units. The International Building Code (IBC) calls for an STC rating of 50 for walls that separate dwelling units, but many designers and developers/owners are questioning if that is really high enough to meet the expectations of occupants.
In response, design professionals seeking to achieve greater acoustical performance without unduly thick walls or creating higher costs are finding that there are options available using sound-reducing gypsum board. Such products are made as gypsum board panels but use a technique known as constrained layer damping (CLD). Products using this technique achieve high sound attenuation and fire resistance in one panel using less space, less material, and less labor than other acoustical treatments.
CLD panels are manufactured with a viscoelastic polymer central layer that allows thin gypsum outer layers to independently shear, thus dissipating the acoustic energy of sound waves. This results in less audible energy passing through the CLD board. Incorporating CLD panels into a wall or ceiling assembly allows for acoustical performance at levels higher than just using standard 1/2” or 5/8” gypsum wallboard. Since only one layer of CLD is often all that is required, the installation is easier, more efficient, and less costly than traditional systems.
Beyond the airborne sound measured by STC, IIC measures a floor/ceiling assembly’s ability to insulate against structure-borne (impact) sound. Structure-borne noise is defined as any noise source whose primary radiation comes from impact (footsteps on an upstairs floor, for example) or vibration of solid structures. IIC is the main metric used in the building industry to characterize structural noise in buildings. As with STC values, the higher the IIC value of a floor/ceiling assembly, the better its ability to reduce the transmission of sound from impacts above. An acceptable IIC rating is typically 50 or above to meet code and user requirements.
In multi-story, multifamily buildings, resident comfort can be notably compromised if impact noise is detected by the occupants below. In these cases, the floor/ceiling assembly becomes the critical point of focus. One successful solution includes the use of thicker, more dense gypsum board for the ceiling material which is specifically formulated to reduce the amount of impact noise being transmitted. This solution has been successful in reducing both airborne and structural noise and is also effective for lower sound frequencies where sound attenuation has proven difficult (see acoustics case study at end of course).
EXTRUDED ALUMINUM TRIM FOR INTERIOR WALLS
Extruded aluminum trim works well not only on the exterior of multifamily buildings but on the inside too. It can be used to frame and hold fast drywall panels, millwork, acoustic ceilings, and even composite panels. The durability of the extruded aluminum is good for the protection of the edges of all those materials and makes them easier to clean. Extruded aluminum products are readily available and are designed to be used with 5/8-inch-thick or ½” thick drywall to provide continuous edge protection for drywall edges and corners. In some cases, the profile of the trim creates a recessed reveal which offers an understated but elegant design while keeping corners and edges protected.
Photo courtesy of Tamlyn
Extruded aluminum trim can be effectively used for smooth transitions between different cladding panel types at inside and outside corners, edges, and other locations.
Similarly, aluminum trim can be used in conjunction with wrapped surface finishes such as fabric or vinyl wall coverings. Such trim pieces are available in a variety of traditional, contemporary, and modern looks to create subdued, elegant looks or emphatic three-dimensional appearances. Since aluminum is highly durable, recyclable, lightweight, and non-combustible, it is a popular and logical choice for interior trim. In addition, the design options, variability, and cost-effectiveness of this trim make them very well suited for both public and private spaces in multifamily buildings.
Aluminum trim products can create a minimalist shadow line with simple reveal space that allows installation vertically, horizontally, or diagonally. They commonly include ridged faces for tape & float connections with gypsum board finishing. They can also include pre-punched holes for easy installations, although hole placement may vary between profiles and products. These products are commonly made from 6063 T5 aluminum with standard clear anodized or primed finish.
Of course, the color and finish of the trim is an important design consideration, regardless of the location. Fortunately, there are many different finish options available including mill finish aluminum, anodized aluminum, standard prefinished color palettes, ready to paint finishes or custom finishing. Extruded aluminum trim can be specified in anodized aluminum in standard colors such as clear, champagne, bronzes and black. Factory prefinished trim can include liquid paint (i.e., acrylics, alkyds, polyesters, and others) or powder coatings, any of which reduces onsite labor needs. At least one manufacturer can provide custom pattern matching on the aluminum to include logos, to match wood panels or stone walls, or even create a wood grain look. Alternatively, it can be specified simply with a paint primer ready to receive final finish coats in the field of virtually any color. With this variety of choices, the trim can appear to blend in with the adjacent wall panels or it can be used to highlight all or some of the visual lines it creates.
This flexibility in using familiar and long-lasting finish options means that both the design and the performance level can be controlled.
DURABLE ELEVATOR CAB INTERIORS
Among the most used interior spaces in a multistory, multifamily building are elevator cabs. Over time, elevator interiors can get damaged, especially if the cab is used for both passengers and other purposes like moving furniture, equipment, etc. Even with the best padded intentions, furniture movers and delivery drivers can ding, gouge, and scuff walls with dollies, carts, and crates.
Photo courtesy of Inpro
Elevator cabs can make a strong first impression on building visitors and occupants as well as be designed to be durable and safe to use.
Some of the main reasons to renovate the cab interior are to update the appearance and make it more appealing by giving it a refreshed look. There may also be an interest in making the cabs more energy efficient with LED lighting or adding extra protection to the cab walls. Another reason to enhance the cab’s appearance is that some people are terrified of elevators and suffer serious anxiety when riding in one. Interior upgrades can help ease those few minutes they spend riding the elevator by providing a more comfortable and appealing experience.
The most cost-effective and innovative way to carry out such an elevator cab upgrade is to use pre-configured elevator cab renovation systems from a manufacturer that has a specialty line of products to address these needs. This system can include any or all of the following elements.
- New Wall Panels: The elevator panels that line the walls are what primarily make up the appearance of the cab. These panels also typically take quite a beating. Fortunately, the panels can be made of durable and rugged materials that can be made to look like any range of materials from wood to metal to stone or custom choices.
- New ceilings and lighting: Elevator ceilings come in many different styles and can be selected to suit an overall design concept. Lighting in elevator cabs can be chosen from among common lamping options such as halogen, incandescent, fluorescent, or energy-efficient LED. Keep in mind that people tend to be more comfortable in a well-lit interior, so combining a brighter ceiling with increased lighting output can help people feel more relaxed inside not to mention creating a newer and cleaner look.
- New Handrails: Handrails in elevators get attention for ADA or accessibility code requirements but they also provide stability for users (i.e., something to grasp) while the elevator stops and starts. This is particularly true for people who are elderly, disabled, or injured and might need help to reduce the risk of a fall. By providing a stand-off surface from the wall of the cab, it can reduce the chance of equipment or furniture striking the wall panels.
Paying attention to both the appearance and durability of elevator cabs can clearly pay off in terms of creating successful, innovative interiors and better experiences for users.
Density in living situations is generally regarded as a good thing in terms of sustainable design, availability of services, provision of mass transit, and other quality-of-life conditions. However, buildings that house multiple households require attention to both design and detail to achieve attractive, desirable, and livable situations. That includes providing the proper balance between public spaces and privacy within dwelling units, especially related to acoustic privacy. There is also the need to provide spaces and materials that are attractive and durable to keep the buildings looking good and performing well over time. The current trends of healthy indoor living environments, green building design, connections to the outdoors, and other design features are all equally important aspects of contemporary multifamily building or renovation design. This course reviews these issues with some specific approaches toward achieving better, coordinated, and budget-friendly outcomes.
Photo courtesy of Inpro
Multifamily buildings are places that create a density and community which are desirable traits, as long as the potential downsides are properly addressed in design.
BETTER BUILDING EXTERIORS
Multifamily buildings are usually part of a larger community setting and in a very real sense, the exterior design helps to shape the nature and character of that community. Architects control that design and can help create exteriors that add vibrancy, provide welcoming environments, and maintain appropriate levels of scale for individual living units.
At the same time, building exteriors need to meet the rigors of energy conservation, sustainability, durability, and cost-effectiveness. For many multifamily buildings, that has meant the use of lightweight cladding used in a rainscreen system for better overall performance. That cladding is often held in place with aluminum trim that is used not only for fastening purposes but to create a visual statement as well. When used successfully, aluminum trim is a design tool that economically creates facades that can be dramatic or subtle, bold or understated, colorful or muted. This gives the trim multiple purposes that can be used to tie into the larger purpose of the community.
Photo courtesy of Tamlyn
Extruded aluminum trim can be used to help secure and frame many different types of exterior cladding edges, such as 36 Dolores, located in Emeryville, California. Architect: Levy Design Partners
Designing with Exterior Aluminum Trim
Not all cladding is the same, so it follows that not all methods of supporting cladding panels are the same. Similarly, different claddings have different capabilities for the edges of panels to be left uncovered or unprotected. This is particularly true if the cladding is porous, such as with wood, cement fiber boards, or some composite products. In these and other cases, aluminum trim is typically used around the perimeter of the cladding.
The design possibilities of using aluminum trim are extensive. There are literally thousands of standard profiles available that can either create a recessed reveal between cladding panels, be flush over the top surface, or can intentionally project outward to accentuate the lines of the design. The aluminum is available in a wide range of standard anodized or painted colors. Extruded aluminum trim can be provided in sizes and styles that work with multiple panels enabling architects to vary the material choices within their façade designs while keeping details that will have a similar language. Used in any of these ways, it has typically been shown to be less expensive with a more elegant look of clean lines than with other options.
Photo courtesy of Inpro
Common or amenity spaces in multifamily buildings can look better longer and help guard against potential hazards when durable, architectural wall and door protection is incorporated into the design.
There is a current design trend to increase the use of non-90-degree corners in urban settings. This may be a response to tighter spaces and building lots or simply a desire for more creative shapes and geometries on building exteriors. Lightweight cladding and aluminum trim have become proven as a means to achieve such angular designs. Manufacturers now provide multi-angle corners that adjust to the angle of the wall for inside and outside corners. This allows for clean, efficient details on non-90-degree corners. Without this option, an installer would need to line up two or more pieces of trim that may or may not end up straight and plumb going up the wall. There are also transition trims available to provide a clean transition from one type of cladding to another. Some two-piece products are also available that allow for easy transition details to keep the architectural design intent intact.
For situations that require it, there is the option of working with a manufacturer to create custom trim profiles to suit the needs of a project. The option also exists for custom coloring for any standard or custom trim profile.
Perhaps the biggest design trend is for architects and designers to use multiple different claddings and trims on a single project or façade. That has obvious implications for the number of different trims that will be needed to work with those different claddings. Clayton Webster, a Product Manager with Tamlyn, notes, "Architects are designing with four or more different claddings on multifamily and single-family construction. The struggle for contractors is to merge those claddings efficiently while keeping the design consistent. Utilizing aluminum trim with transition profiles allows architects the ability to design freely and gives contractors the solution they need to address the transition between the different claddings."
SUSTAINABLE INTERIORS
A big part of creating a sustainable multifamily building is the durability of the interior areas, especially those that get heavier use. Incorporating protective architectural products on walls and other surfaces helps to increase the longevity of multifamily buildings while also protecting occupants from potential hazards. This is particularly true for amenity areas such as common rooms, exercise areas, and café areas as well as circulation spaces such as corridors, stairways, doors, and elevators. Protection in all of these areas is not limited just to foot traffic and people but also needs to address protection from equipment for moving tenants in and out, cleaning equipment, deliveries, and things needed for special events.
Multifamily buildings therefore can be most sustainable when owners invest in products that protect the interior wall and door surfaces allowing the building to last longer and saving resources like time and money in the long run. The alternative is to regularly go through costly and time-consuming updates, especially to justify any increases in rent prices. Instead of needing to replace surfaces and interior features every three years, it is now reasonable to expect 10–15-year service lives by using architectural protective products.
Incorporating effective architectural protection doesn’t mean that performance and aesthetics have to compete with each other. There are plenty of different protective products for multifamily buildings that can be aesthetically pleasing and even innovative in the way they are manufactured and used. The best approach is referred to as targeted wall protection where a specific set of products is used that are designed to absorb impact and protect the underlying portion of the wall. By targeting the most vulnerable areas, protection can be added by using corner guard or wall guard products specifically where they are needed. These can include horizontal rails across targeted sections of the walls as well as vertically installed corner guards. Since many of these products can be specified with materials that are not only durable but also easy to clean, they help protect the building as well as the people in them.
Taking the concept of wall protection further, sheets of rigid wall covering have been used where large surfaces need to be made more durable and easier to clean. Usually produced in sheets or rolls, rigid vinyl extruded wall cladding comes in several standard thicknesses. For medium-duty installations, .028 is used when flexibility is needed such as wrapping a column for example. A slightly heavier .040 can be used to eliminate re-painting where repeated scuffing wears through the top layer of drywall. For heavier-duty locations, .060 is used to protect against gouging of the wall while .080 is used for maximum protection, often installed on top of cement board or fire-rated plywood. Most of these products offered in the U.S. are Class A fire rated with many choices of product types, finishes, and colors to enhance, rather than detract from, an interior design scheme.
For wall areas that need some protection but desire a softer look, resilient, textured wall covering is available which brings several advantages. A thicker wall covering with special top coatings makes for a very durable product. That includes resistance to chemicals and cleaning agents. Such wall coverings can also be selected which are quite cleanable and resilient against stains, markings, and graffiti. From a design standpoint, there are textured wall coverings available in a variety of colors and patterns that can be combined with other wall protection products from a manufacturer for a totally coordinated look.
Photo courtesy of PABCO Gypsum
CLD gypsum board uses viscoelastic polymers (damping layer) between two layers of gypsum (constraining layers) to reduce sound and vibration in building partitions. When under vibration, the damping layer shears as the panel flexes resulting in less overall sound energy transmitted through the panel.
CONTROLLING SOUND USING GYPSUM PANELS
Residents of multifamily buildings, whether condos, apartments, co-housing units, or other types, all have a fundamental need for some acoustic privacy. They really don’t want to hear their neighbors in an adjacent unit on either side, above, or below them and they certainly don’t want to feel like those neighbors can hear what they are saying or doing. Therefore, reducing the noise transfer from one living unit to another and between a living unit and a common area (hallways, community room, amenity spaces, etc.) can result in more satisfied owners and renters, less turnover, and fewer vacancies.
From a design perspective, achieving this common goal of acoustic privacy means calling for wall assemblies and floor/ceiling assemblies with adequate Sound Transmission Class (STC) and Impact Insulation Class (IIC) ratings. The higher the STC or IIC rating for a particular assembly, the less sound that is transferred between units. The International Building Code (IBC) calls for an STC rating of 50 for walls that separate dwelling units, but many designers and developers/owners are questioning if that is really high enough to meet the expectations of occupants.
In response, design professionals seeking to achieve greater acoustical performance without unduly thick walls or creating higher costs are finding that there are options available using sound-reducing gypsum board. Such products are made as gypsum board panels but use a technique known as constrained layer damping (CLD). Products using this technique achieve high sound attenuation and fire resistance in one panel using less space, less material, and less labor than other acoustical treatments.
CLD panels are manufactured with a viscoelastic polymer central layer that allows thin gypsum outer layers to independently shear, thus dissipating the acoustic energy of sound waves. This results in less audible energy passing through the CLD board. Incorporating CLD panels into a wall or ceiling assembly allows for acoustical performance at levels higher than just using standard 1/2” or 5/8” gypsum wallboard. Since only one layer of CLD is often all that is required, the installation is easier, more efficient, and less costly than traditional systems.
Beyond the airborne sound measured by STC, IIC measures a floor/ceiling assembly’s ability to insulate against structure-borne (impact) sound. Structure-borne noise is defined as any noise source whose primary radiation comes from impact (footsteps on an upstairs floor, for example) or vibration of solid structures. IIC is the main metric used in the building industry to characterize structural noise in buildings. As with STC values, the higher the IIC value of a floor/ceiling assembly, the better its ability to reduce the transmission of sound from impacts above. An acceptable IIC rating is typically 50 or above to meet code and user requirements.
In multi-story, multifamily buildings, resident comfort can be notably compromised if impact noise is detected by the occupants below. In these cases, the floor/ceiling assembly becomes the critical point of focus. One successful solution includes the use of thicker, more dense gypsum board for the ceiling material which is specifically formulated to reduce the amount of impact noise being transmitted. This solution has been successful in reducing both airborne and structural noise and is also effective for lower sound frequencies where sound attenuation has proven difficult (see acoustics case study at end of course).
EXTRUDED ALUMINUM TRIM FOR INTERIOR WALLS
Extruded aluminum trim works well not only on the exterior of multifamily buildings but on the inside too. It can be used to frame and hold fast drywall panels, millwork, acoustic ceilings, and even composite panels. The durability of the extruded aluminum is good for the protection of the edges of all those materials and makes them easier to clean. Extruded aluminum products are readily available and are designed to be used with 5/8-inch-thick or ½” thick drywall to provide continuous edge protection for drywall edges and corners. In some cases, the profile of the trim creates a recessed reveal which offers an understated but elegant design while keeping corners and edges protected.
Photo courtesy of Tamlyn
Extruded aluminum trim can be effectively used for smooth transitions between different cladding panel types at inside and outside corners, edges, and other locations.
Similarly, aluminum trim can be used in conjunction with wrapped surface finishes such as fabric or vinyl wall coverings. Such trim pieces are available in a variety of traditional, contemporary, and modern looks to create subdued, elegant looks or emphatic three-dimensional appearances. Since aluminum is highly durable, recyclable, lightweight, and non-combustible, it is a popular and logical choice for interior trim. In addition, the design options, variability, and cost-effectiveness of this trim make them very well suited for both public and private spaces in multifamily buildings.
Aluminum trim products can create a minimalist shadow line with simple reveal space that allows installation vertically, horizontally, or diagonally. They commonly include ridged faces for tape & float connections with gypsum board finishing. They can also include pre-punched holes for easy installations, although hole placement may vary between profiles and products. These products are commonly made from 6063 T5 aluminum with standard clear anodized or primed finish.
Of course, the color and finish of the trim is an important design consideration, regardless of the location. Fortunately, there are many different finish options available including mill finish aluminum, anodized aluminum, standard prefinished color palettes, ready to paint finishes or custom finishing. Extruded aluminum trim can be specified in anodized aluminum in standard colors such as clear, champagne, bronzes and black. Factory prefinished trim can include liquid paint (i.e., acrylics, alkyds, polyesters, and others) or powder coatings, any of which reduces onsite labor needs. At least one manufacturer can provide custom pattern matching on the aluminum to include logos, to match wood panels or stone walls, or even create a wood grain look. Alternatively, it can be specified simply with a paint primer ready to receive final finish coats in the field of virtually any color. With this variety of choices, the trim can appear to blend in with the adjacent wall panels or it can be used to highlight all or some of the visual lines it creates.
This flexibility in using familiar and long-lasting finish options means that both the design and the performance level can be controlled.
DURABLE ELEVATOR CAB INTERIORS
Among the most used interior spaces in a multistory, multifamily building are elevator cabs. Over time, elevator interiors can get damaged, especially if the cab is used for both passengers and other purposes like moving furniture, equipment, etc. Even with the best padded intentions, furniture movers and delivery drivers can ding, gouge, and scuff walls with dollies, carts, and crates.
Photo courtesy of Inpro
Elevator cabs can make a strong first impression on building visitors and occupants as well as be designed to be durable and safe to use.
Some of the main reasons to renovate the cab interior are to update the appearance and make it more appealing by giving it a refreshed look. There may also be an interest in making the cabs more energy efficient with LED lighting or adding extra protection to the cab walls. Another reason to enhance the cab’s appearance is that some people are terrified of elevators and suffer serious anxiety when riding in one. Interior upgrades can help ease those few minutes they spend riding the elevator by providing a more comfortable and appealing experience.
The most cost-effective and innovative way to carry out such an elevator cab upgrade is to use pre-configured elevator cab renovation systems from a manufacturer that has a specialty line of products to address these needs. This system can include any or all of the following elements.
- New Wall Panels: The elevator panels that line the walls are what primarily make up the appearance of the cab. These panels also typically take quite a beating. Fortunately, the panels can be made of durable and rugged materials that can be made to look like any range of materials from wood to metal to stone or custom choices.
- New ceilings and lighting: Elevator ceilings come in many different styles and can be selected to suit an overall design concept. Lighting in elevator cabs can be chosen from among common lamping options such as halogen, incandescent, fluorescent, or energy-efficient LED. Keep in mind that people tend to be more comfortable in a well-lit interior, so combining a brighter ceiling with increased lighting output can help people feel more relaxed inside not to mention creating a newer and cleaner look.
- New Handrails: Handrails in elevators get attention for ADA or accessibility code requirements but they also provide stability for users (i.e., something to grasp) while the elevator stops and starts. This is particularly true for people who are elderly, disabled, or injured and might need help to reduce the risk of a fall. By providing a stand-off surface from the wall of the cab, it can reduce the chance of equipment or furniture striking the wall panels.
Paying attention to both the appearance and durability of elevator cabs can clearly pay off in terms of creating successful, innovative interiors and better experiences for users.
Fire-Rated Aluminum Trim
A new addition to the market of aluminum trim products is the offering of fire-rated profiles to enhance the already extensive selection of extruded aluminum trim. The fire rating is achieved through the addition of a factory-applied intumescent strip along the back wall of the profile. This enables certain drywall designs to achieve 1-hour and 2-hour fire ratings without the requirement of an extra layer of drywall. The intumescent strip expands when exposed to increased heat during a fire and will completely seal off the gap in drywall preventing the passage of fire.
Fire-rated profiles are independently fire tested per ASTM E119 “Standard Test Methods for Fire Test of Building Construction and Materials.” Under this test, a sample wall panel is subjected to a large-scale vertical exposure furnace. During the test, no flames can pass through the assembly and the average ambient temperature on the outside of the wall cannot pass 139 degrees Celsius nor a single point temperature of 181 degrees Celsius. Following the direct heat exposure, the test then calls for a water hose stream to be sprayed onto the fire-exposed panel to simulate a firefighting condition. The hose stream flows for 2-1/2 minutes and must not permit the projection of water from the hose stream beyond the unexposed surface. Fire-rated interior trim has been successfully subjected to this test for 120 minutes as part of an overall wall assembly and sprayed with water at 30 psi and met all of the testing requirements. Therefore, it has been certified for a 120-minute (2 hour) fire rating. Fire-rated extruded aluminum trim is generally available in standard lengths of 10 feet.
GYPSUM AREA SEPARATION WALLS
When two living units share an adjoining wall, then those assemblies need to be fire-resistance rated per applicable building codes in order to provide the appropriate area separation. Non-load-bearing gypsum Area Separation Firewall systems (ASWs), which can also include CLD panels, provide the advantages of both fire resistance and noise reduction between neighboring townhouses and other attached dwelling units up to (in most cases) six stories in height. Gypsum ASWs are efficient to construct and offer a 2-hour fire resistance rating. As such, they can provide code-compliant walls with sound ratings exceeding STC-60.
Gypsum ASWs offer considerable advantages over masonry or other materials used for creating the code-compliant ASW. Gypsum construction provides a thinner profile allowing up to 6 inches of additional usable floor space compared with a typical concrete block wall. The lighter weight of the framed gypsum wall also means a smaller footing or foundation is required. Gypsum ASWs allow construction efficiency and safety to increase since they are installed one course (or floor) at a time, just like the rest of the building. Scaffolding is not required, and the risk of toppling masonry walls is completely eliminated. Weather-related concerns and scheduling problems related to bringing in additional trades are also not an issue; there is no mortar to freeze or be compromised by cold weather work.
Photo courtesy of PABCO Gypsum
Interior gypsum products, when specified and installed properly, provide sound control, fire resistance, and positive indoor environmental quality in multifamily buildings.
Interior Cordless Shades
Controlling daylight and glare from windows is a design necessity for comfortable multifamily units and common areas in particular. In response, textured roller shades can be used which allow diffused daylight to pass through a fabric appearance that reduces the total light transmission. In this way, they reduce glare, add comfort, and produce a favorable light quality inside the building. At the same time, they provide a degree of privacy or muted views through to the outdoors. In terms of energy performance impact, interior sunshades can help with the rejection of solar heat and have a positive impact on reducing energy needs for cooling as a result.
While shade systems are available that use chains or cords to raise and lower them, there are also products available that are completely cordless. Such cordless window shades are a logical choice where the presence of dangling cords can be a safety hazard for children. Rather than trying to contain or conceal the cords, the elimination of them dispels any potential problem. Cordless shades commonly use a spring roller system that allows for direct and easy manual adjustment of the shade with the capability to raise and lower it to any height.
Photo courtesy of Inpro
Interior cordless window shades with textured fabric can provide privacy or maintain connections to the exterior while helping with energy performance by reducing solar heat gain.
Beyond these functional features, it is possible to design and incorporate custom printing of the shades with a graphic design selected by the designer. Printed shades can create a welcoming atmosphere in addition to hiding any unsightly outdoor views. They’re also less likely to be damaged or vandalized. It is entirely possible to use custom landscapes, artwork, or even logos for the shades. Of course, standard fabric patterns can also be applied to a shade for simplicity.
EXTERIOR TRIM PERFORMANCE
Aluminum trim, in both 1-piece and 2-piece solutions, can be specified in common thicknesses and profiles to suit any of the lightweight cladding materials commonly in use. It is manufactured to work with wood lap siding, fiber cement panels, composite panels, metal panels, and almost any other common building material. When used to hold the edges of exterior wall panels or siding, it provides architects with a unique means to detail corners, vertical and horizontal joints, and material transitions with durability and integrity.
As a material, extruded aluminum is a common building material favored for its versatility, inherent strength, and durability. Aluminum is durable and long-lasting making it a great material for trim details to last for years. A lot of architects receive requests to use steel flashings instead of aluminum. This substitution may provide a reduced material cost, but within a year of the project being completed, steel trim is often oil-canning and wavy along the wall. Aluminum trims are more durable and sustainable and provide a clean extrusion profile. Aluminum expansion and contraction is far less than steel which helps keep the integrity of the trim.
Most extruded shapes for architectural use are fabricated from 6063 aluminum alloy, with magnesium and silicon as the alloying elements. Type 6063-T5 Aluminum, commonly referred to as the architectural alloy, has a very smooth surface and is the best alloy suited for anodizing applications. The T5 designation indicates it has been artificially aged and moderately heat-treated. Aluminum extrusion is a highly versatile metal-forming process that has a wide array of physical characteristics. In all cases, extruded aluminum is a sustainable material, commonly with 75 percent to 100 percent postindustrial and post-consumer content. As such, extruded aluminum trim can contribute to LEED points for buildings seeking certification or green building status.
The installation of extruded aluminum trim is typically very straightforward. In particular, two-piece extruded aluminum profiles are recommended for greater construction efficiency in handling tougher detailing situations. The two-piece design permits application of the base part first and then installation of the cover cap afterward. In tight-fit situations, this may be more efficient compared to using the standard trim pieces for inside or outside corners or for transitions. Due to the natural expansion and contraction of aluminum, all two-piece caps must be secured by adhesive or other means as approved by the manufacturer.
Photo courtesy of Tamlyn
Modern and contemporary designs can be created using either 1-piece or 2-piece aluminum trim products that provide long term performance as shown here at Marketplace Apartments in Lansing, Michigan. Architect: Johnson Nathan Strohe
EXPANSION JOINTS
Architectural expansion joints, predetermined gaps in large structures that are designed to absorb environmental movement in buildings, are necessary. When done right, they tend to be integrated with their construction such that they blend in with a design and almost disappear. In large multifamily buildings, they are a necessity, particularly where buildings are segmented into different sections or if they attach to another structure such as a parking garage or other commercial use.
Photo courtesy of Inpro
Properly selected and specified expansion joint systems and covers can blend into a multifamily building while providing the necessary protection against building movement.
Building sections can move due to several common reasons. When it comes to expansion control in buildings, there are three types of movement that need to be accommodated:
- Thermal Forces This type of movement is most typical and caused by daily environmental temperature changes in and around the structure. Thermal movement is primarily “one-directional” in nature and is the result of the expansion and contraction of structural elements as affected by heat, cold, and humidity levels. If expansion joints aren’t put in, then thermal expansion and contraction can cause buckling of surfaces in place like roofs and interior floors.
- Seismic Activity The shifting of the earth’s tectonic plates (i.e., earthquakes, tremors, etc.), and shifts along fault lines is the source of seismic activity. Seismic movement may be horizontal, vertical, in shear, or a combination of all three. Seismic expansion joint widths may need to increase with higher floor levels to accommodate the additional, cumulative movement that needs to be addressed. When it comes to expansion joint systems, it is important to select systems that can “reset” themselves after a minor seismic event and allow workers to reposition panels easily.
- Wind-loads Movement induced by high winds, can force the structure to sway. This movement is normally perpendicular and/or parallel to the joint. This is common where a low horizontal building span meets with a taller vertical element, such as the lobby of a multifamily or mixed-use building that is adjacent to a high-rise building section. Therefore, when designing a structure, it must be able to both withstand high wind loads but also work with them. As with seismic activity, expansion joint systems should be able to “flex” and yet remain in place as the building sways or torques.
Matthew Fisher is the Expansion Joint Systems Manager for Inpro. He encourages design professionals to look closely at the way the building is going to be used by asking questions. He queries “Does the owner utilize equipment such as scissors lifts for lighting changes in high ceiling areas? Are heavy loads of furniture and dollies going to be routinely rolled over the floor for tenant move-in and move-out situations? It is usually best to ensure the worst-case scenarios are considered when specifying systems.” In his experience, a slightly higher front-end cost on the right expansion joint system may go a long way toward alleviating an ongoing facility maintenance headache for years to come.
INDOOR ENVIRONMENTAL QUALITY IN BUILDINGS
A trend among multifamily renters and buyers is to be cognizant of the Indoor Air Quality (IAQ) within and around buildings and structures, especially as it relates to human health and comfort. The general public is increasingly aware of the types of common pollutants or materials used in buildings that carry potential health risks. Therefore, architects and others in the design and construction field have increasingly been considering the following when specifying building materials:
- Red List Free Materials: The International Living Futures Institute (LFI) has developed the Living Building Challenge (LBC) as a means to design and document buildings that go beyond sustainability. They have undertaken an extensive study of materials and compounds that can be found in building products and created a “Red List” of those that should not be used if a healthy indoor environment is sought. Manufacturers can compare the ingredients in their products against this list and follow the protocol of the ILFI “Declare” labels to inform the public of the relative health safety of construction. For a manufacturer to claim its product is LBC Red List Free, it must first disclose 99 percent of ingredients and residuals present at or above 100 ppm or 0.01 percent. The product may contain one or more Red List chemicals, but only if covered by an established exception. More information is available at: https://living-future.org/red-list/
- Certified Low VOC Emissions: Volatile organic compounds (VOCs) (including formaldehyde), are substances that are potentially emitted from building materials that can adversely impact human health. It is often found in materials that contain binders, glues, adhesives, coatings, and the like. The good news is that many products are now available with reduced levels of VOCs or, even better, are formulated to be VOC-free. The US Green Building Council has included a focus on low VOCs in all versions of the LEED green building rating system and is a good resource for more information on this topic. https://www.usgbc.org/credits/new-construction-core-and-shell-schools-new-construction-retail-new-construction-data-38
- Non-Detect Asbestos: From the 1930s to the 1980s, asbestos-based drywall was popularly used in residential, commercial, and industrial structures. Beyond the individual drywall sheets, joint tapes and compounds also incorporated asbestos additives. While this material had great fire resistance properties, it also exposed building occupants and construction workers to a serious health hazard when the asbestos fibers became airborne and were inhaled. In response, asbestos is no longer permitted for use in drywall sheets, tapes, and joint compounds making them much safer to use today. As a matter of enforcement, U.S. Government agencies conduct thorough investigations of gypsum plants to determine if any asbestos is detectable in their products. Those that prove they use only naturally occurring gypsum, and no asbestos in their products, receive notice that no asbestos is detected, and their products are safe to use. For renovation projects it may be helpful to refer to: https://www.airpf.com/identifying-sheetrock-asbestos-what-does-asbestos-drywall-look-like/
- Respirable Silica: A more recent focus has been on the health hazards of silica dust which can be inhaled. Prolonged exposure to silica can lead to serious health issues such as silicosis, lung cancer, and other respiratory diseases. Silica testing can determine if dust contains crystalline forms of silica (quartz, cristobalite, and tridymite) that may cause silicosis, lung disease, or is a known carcinogen to humans. It is therefore recommended to follow good work practices to minimize dust generation from all building products, including gypsum products. Industrial hygiene tests are also recommended to determine the actual exposure at the worksite due to the inherent variability of each project.
- Mold Resistance: Mold has the potential to cause health problems since it can produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins). Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals. Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis). Mold-resistant gypsum panel products provide enhanced protection against mold and moisture in areas such as kitchens and bathrooms.
Acknowledging the causes of indoor air quality issues and specifying the appropriate gypsum board products to address those issues can go a long way toward preventing potential health issues for everyone involved in multifamily housing. Given all of these attributes, it is not surprising that gypsum has become the material of choice for many multifamily buildings. Deborah Callaway, Manager, Technical Services, at PABCO Gypsum has been directly involved in working with architects and construction professionals on many multifamily buildings. She observes that, “A full variety of gypsum products are available to provide solutions to the many challenges inherent in multifamily construction. Whether acoustics, fire protection, or indoor air quality, gypsum panels can meet those needs that are important for a comfortable and safe space.”
Photo courtesy of PABCO Gypsum
Manufacturers who complete an extensive review of the ingredients in their products can strive to avoid any items on the Living Building Challenge “Red List” to create healthier indoor environments.
CONCLUSION
Creating well-designed, sustainable, and comfortable multifamily housing is a multi-faceted task. Interiors need to be attractive and durable, including the interior of elevators. Gypsum board should be specified to match the varied needs of acoustic control, fire protection, and indoor environmental quality. Innovative materials like aluminum trim can be used to enhance the building’s exterior and interior. Large buildings require expansion joints to protect against inevitable movement. The strategies discussed in this course can help architects and designers address these multiple design criteria to meet the needs of the building owner, the occupants, and the environment.
Peter J. Arsenault, FAIA, NCARB, LEED AP is a nationally known architect and a prolific author advancing positive acoustical experiences through better building design. www.pjaarch.com, www.linkedin.com/in/pjaarch
