|Healthcare facility designs have advanced dramatically in recent years, resulting in more aesthetic and comforting environments, yet the underlying structural systems have remained much the same for decades. To improve energy efficiency and indoor air quality, lower interior noise, reduce building cycle times, and cut-down on construction waste, design professionals are looking more closely at the building envelope. Structural Insulated Panels (SIPs) are one advanced building technique many are now using to meet these needs.|
|Hospital administrators are dealing with a myriad of changes and uncertainties from healthcare reform to worker cutbacks to liability concerns. Designing and constructing higher performance buildings is one way to help them meet the growing pressures of a difficult industry. On the facility design and operations front, finding ways to reduce building and operating costs, while still ensuring quality, is especially critical.|
|Healthcare facility designs have advanced dramatically in recent years, resulting in more aesthetic and comforting environments, yet the underlying structural systems have remained much the same for decades. To improve energy efficiency and indoor air quality, lower interior noise, reduce building cycle times, and cut-down on construction waste, design professionals are looking more closely at the building envelope. Structural Insulated Panels (SIPs) are one advanced building technique many are now using to meet these needs in community hospitals, private clinics, long-term care facilities, and other low-rise healthcare buildings.
Structural insulated panels provide many benefits compared to other light commercial construction options such as stick-built framing, concrete masonry units (CMUs), and tilt-up concrete. They are engineered components composed of two outer sheathing layers, or “skins,” laminated to a rigid insulating foam core. These structural units take the place of individual wall studs and floor or roof joists, as well as blown-in or fiberglass batt insulation.
SIPs are strong, and in most applications are structurally self-sufficient. Designers can use them to bear high loads (including those from gravity, snow, high winds, and seismic forces) in wall, roof, and floor applications in place of other structural elements.
Design professionals can incorporate SIPs into typical exterior walls, as well as shear walls to resist earthquakes and high winds. Extensive testing has proven that SIPs work well in high-risk earthquake areas, including seismic design categories D, E, and F.
Available in sections up to 8′ × 24′, SIPs allow for straight and even walls. In roofs, the panels can be used without an engineered truss system and can span long distances—up to 20 feet based on design parameters. As a result, they can help create open interior spaces by reducing the need for intermediate structural supports. In a healthcare setting this provides room for persons with assistive devices or limited mobility or vision to move around safely with less navigation obstacles.
Given their strength, SIPs work well in both single- and multistory, low-rise buildings. As with other wood-framed construction, the practical limit on building height for SIPs comes from the fire restrictions imposed by Type V construction (typically four stories), more so than load-bearing capability. Even so, fire investigators have found that in buildings constructed of SIPs, the panels held up well.
Superior insulating properties
The SIPs’ solid foam core greatly reduces air movement within walls. Since there are no studs within them, SIPs have fewer thermal bridges than stick-built framing. As such, SIPs dramatically improve energy efficiency, help improve indoor air quality, and reduce outside noise.
A study by the Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL) found that SIPs construction is 15 times better at stopping air infiltration than standard wood framing.
The lab also evaluated the whole-wall R-values of structural insulated panels versus stick framing. Their tests accounted for energy loss through the structural members, corners, joints, and around windows. Such assessment provides a more complete picture of the insulating capacity of a wall assembly, beyond just the insulation’s R-value. They found that a 3.5-inch thick core SIP had a whole-wall R-value of 14.09. In contrast, a wall framed with 2″ × 4″ studs at 16″ on center spacing had a whole-wall R-value of 9.58. Therefore, the SIP wall had a 47% higher whole wall R-value. read more