“Buildings don’t fail because of one issue, they fail at the interfaces,” says Lisa Semling, Product & Innovation Manager, Commercial Building Infrastructure, Saint-Gobain North America.

These challenges are well known to building scientists and enclosure specialists. Across projects and performance evaluations, a consistent pattern emerges: hospitals perform best when the building envelope is treated as a system - not a collection of parts.

As healthcare design responds to climate pressures, aging infrastructure, and increasingly complex renovation cycles, the industry must move beyond fragmented specification toward integrated, continuous envelope design.

The Limits of Fragmented Design

Traditional specification practices treat building systems as discrete scopes, from below- grade waterproofing, air and weather resistive barriers, roofing systems, fireproofing, to interiors, each designed to meet individual performance criteria. In practice, building performance is defined at the interfaces between those systems.

Transitions between assemblies, penetrations, and inconsistencies in detailing are common sources of failure. These conditions allow moisture intrusion, air leakage, and long-term degradation to develop, often undetected until performance is compromised.

Addressing these risks requires a shift in approach: designing for continuity rather than components. The building envelope must be treated as a coordinated whole, not a siloed collection of disparate products and systems. Performance is defined by how materials connect across transitions: below-grade to wall, wall to roof, and deck interfaces.

Integrated systems reflect this evolution by aligning materials, detailing, and technical support across the full building envelope, from foundations through vertical walls and into roofing assemblies. This approach brings together below-grade waterproofing, air and weather resistive barriers, roofing, and additional critical elements to building performance such as glazing systems, fireproofing, and interiors, that are designed, tested, and supported to work together.

By reinforcing transitions with compatible materials and coordinated detailing, and supporting them with a unified, single-source warranty, integrated approaches reduce risk, simplify installation, and improve long-term performance.

Start Where Failure Begins: Below-Grade Protection

Below-grade conditions represent one of the highest-risk areas in healthcare construction, and one of the least forgiving. Once installed, these systems are no longer accessible. Failures are difficult to diagnose and even more difficult to repair, particularly in occupied facilities.

“You only get one shot to get it right below-grade,” said Lisa Semling.

Hospitals frequently encounter sustained hydrostatic pressure and contaminated soils. Without a continuous, fully-bonded barrier, water can penetrate small, often unavoidable punctures in non-bonded membranes and migrate laterally between the membrane and concrete until it finds a path into the building.

Fully-bonded waterproofing systems adhere directly to the substrate, helping prevent water migration even under sustained pressure. Alternative fully-bonded technologies are selected based on site conditions, risk profile, and project requirements. When coordinated with adjacent air and weather resistive barriers, these systems form a continuous defense against water.

Below-grade performance is not just about the membrane, it is about how that membrane interacts with the structure itself.

“Your waterproofing system is going to work in tandem with your concrete. These are two sides of the same coin,” noted Semling.

Through Saint-Gobain’s Chryso concrete admixture technologies, there is a growing emphasis on understanding how concrete quality and waterproofing performance are interdependent. Poor concrete quality can affect membrane adhesion and long-term durability, reinforcing the need to approach the foundation as an integrated assembly.

Recently, this system-based approach was put into practice on the North Tower development, part of a leading healthcare campus in Seattle, where envelope continuity and risk reduction were critical design drivers.

GCP was initially specified to provide their PREPRUFE® below-grade waterproofing system for the Seattle hospital project. And, a competing product was the basis of design for the above-grade air barrier, with GCP listed only as an alternate. The air barrier applicator initially bid the specified product, but the general contractor recognized the risks associated with fragmented systems, particularly at the transition between below-grade waterproofing and above-grade assemblies.

To address these concerns, the project team ultimately selected GCP’s PERM-A-BARRIER® Air Barrier System, aligning both below- and above-grade components under a single manufacturer. GCP’s technical team demonstrated how a unified system could eliminate compatibility issues at critical tie-ins, reduce installation complexity, and improve overall performance.

The project ultimately leveraged Saint-Gobain’s 6Sides+ system to provide continuous protection from below-grade foundations through vertical walls. By using materials engineered and tested to work together, and supported by a unified warranty, the team reinforced continuity across one of the most failure-prone areas of the building.

Air & Moisture Control: Managing the Invisible Risks

Many performance issues develop within wall assemblies, where uncontrolled air movement and vapor can create conditions for condensation and microbial growth. In healthcare settings, these risks extend beyond durability, they directly affect infection control and occupant health.

Air barrier systems must not only control air leakage but also integrate seamlessly with adjacent materials across the envelope. Membranes and accessories tested to perform together support consistent installation, code compliance, and long-term durability.

Vapor control also plays an essential role in managing moisture within assemblies. Solutions like CertainTeed’s MemBrain™ smart vapor retarder adapt to changing humidity conditions, helping regulate moisture levels while supporting energy efficiency and long-term durability across both residential and commercial applications.

Field support is equally critical, ensuring design intent is maintained during installation, particularly at transitions and penetrations where failures most often occur.

“Everything is connected, what happens above- and below-grade affects the air people breathe,” says Lisa Semling.

Even small discontinuities can compromise both durability and indoor environmental quality over time.

The Roof: First Line of Defense Against Heat and Weather

The roof is both a primary weather barrier and a key driver of energy performance. Healthcare facilities operate with high internal loads, making solar heat gain a significant factor in cooling demand and occupant comfort.

“Heat isn’t just a building-level energy and comfort issue, it’s also an urban heat island issue,” said Galen Burrell, Senior Building Science Strategist at Saint-Gobain North America. “In aggregate, reflective roofs have a significant impact on reducing local ambient temperatures in the communities in which they reside.”

High-performance roofing systems are designed to reduce thermal loading while maintaining durability under environmental exposure. Reflective assemblies, such as CertainTeed’s Flintlastic® CoolStar® Ultra family of solutions help limit solar heat gain, supporting more stable indoor conditions.

Multi-layer roofing systems also provide redundancy against water intrusion, while self-adhered application methods improve jobsite control, particularly in active healthcare environments.

When coordinated with wall and air barrier systems, the roof reinforces overall enclosure performance.

Fire Protection: Designing for Containment and Continuity

Fire protection in healthcare facilities is not simply about meeting code, it is about maintaining structural integrity, enabling safe egress, and containing fire long enough to protect occupants who may not be able to evacuate quickly.

That requires a shift in thinking - from individual materials to system performance.

One of the biggest takeaways in building science, particularly in fire safety, is that performance should be evaluated at the system-level, not at the product-level.

Fire resistance is inherently a system-level property. Walls, floors, shafts, and structural and finish elements must work together to limit incipient fire growth, slow down the propagation of fire across compartments, and maintain the structural integrity of the building. Even small deviations in assembly, fastener spacing, material substitutions, or detailing, can affect performance.

Compartmentalization remains a critical passive strategy in healthcare design, helping isolate fire events and protect patient areas, corridors, and vertical egress paths.

Solutions such as GlasRoc® Shaftliner Type X by CertainTeed support these assemblies with a reinforced fiberglass mat that enhances durability, moisture resistance, and mold resistance, key considerations in healthcare environments.

For structural steel, spray-applied fire-resistive materials like GCP’s MONOKOTE® provide essential protection by protecting steel and helping maintain load-bearing capacity under high temperatures. While steel is non-combustible, it can lose strength rapidly in a fire without protection.

In healthcare facilities, where time is critical, fire protection must perform exactly as designed.

Interior Systems: Hygiene, Durability & Infection Control

Interior materials must withstand demanding conditions while supporting infection control protocols and long-term durability.

“In healthcare, durability isn’t just about service life, it’s about maintaining a safe, hygienic environment,” said Lucas Hamilton, Manager, Applied Building Science at Saint-Gobain North America.

Material consistency across assemblies also supports continuity in performance and installation.

Balancing Comfort & Performance: Light, Heat & Acoustics

Environmental conditions within healthcare facilities have a measurable impact on both patient outcomes and staff performance. Daylight, thermal comfort, and acoustics all play a role in creating spaces that support healing, reduce stress, and enable focused clinical work.

Daylight, for example, is closely linked to circadian rhythm, mood, and recovery. But it must be carefully controlled to avoid glare and overheating. Dynamic glazing systems help manage solar heat gain and glare while maintaining access to daylight and views. 

Research has shown that managing solar heat gain and glare can improve occupant comfort and reduce reliance on mechanical cooling in healthcare environments. Technologies such as dynamic glazing support more stable interior conditions by responding to changing daylight and heat levels throughout the day.

Acoustic performance is another essential, and often underappreciated, factor. In healthcare settings, sound control supports patient recovery, reduces stress, and enables clear communication among care teams. It is also critical for speech privacy and regulatory compliance, including HIPAA requirements.

Sound isolation is typically achieved through wall and ceiling assemblies, where systems such as CertainTeed’s SilentFX® QuickCut™ drywall can help reduce sound transmission between spaces. At the same time, sound absorption plays a key role in minimizing reverberation and background noise. Acoustic ceiling systems, such as CertainTeed’s Symphony® RX series, are designed to support both acoustic comfort and cleanability requirements in healthcare environments.

When integrated with the broader interior and envelope systems, including ceiling grids and support structures, these solutions contribute to a more controlled, comfortable, and high-performing environment.

Advancing Toward Integrated Performance

Failures rarely originate from a single system, they occur where continuity is lost.

As healthcare design evolves to address climate volatility, aging infrastructure, and increasingly complex renovation cycles, the industry is placing greater emphasis on building science to inform more resilient, adaptable designs.

“We can’t just design for yesterday’s climate, we have to design for what’s coming,” said Galen Burrell, Senior Building Science Strategist, Saint-Gobain North America.

Across the industry, this shift is driving a deeper focus on how assemblies interact over time, prioritizing resilience, passive survivability, and long-term durability as system-level outcomes.

Organizations investing in building science, including Saint-Gobain North America, that has one of the largest building materials footprints in North America, are helping project teams better understand where risks concentrate and how continuity can be reinforced across the full building envelope - from foundation to roof.

By moving beyond fragmented specification and toward coordinated, system-based design, project teams can better manage risk, improve constructability, and support long-term performance in critical healthcare environments.

Ultimately, resilience depends on systems that are tested, compatible, and proven to perform together.