Putting High-Performance Roof systems to Work at APS

Spotlight on zs2 + impermitek

At Alaska Precast Solutions, our focus on durable, high-performance construction extends beyond the structure itself. A building's long-term performance also depends on its complete envelope—from insulation and thermal continuity to moisture management and waterproofing.

At our Nikiski site, we're putting that approach into practice with ZS2 magnesium oxide building products and Impermitek waterproof coatings on both the APS Manufacturing Plant and Precast Prototype Home. Because the two buildings use fundamentally different structural systems, the roof assemblies—and the ZS2 products within them—are different as well.

APS Manufacturing Plant:
Zs2 TechBoard + Impermitek

The 54,000-square-foot APS Manufacturing Plant was constructed using insulated concrete forms (ICF), since the facility needed to be built before we could manufacture our own precast products.

For its large industrial roof, we selected 1/4-inch ZS2 TechBoard® in 4' x 8' sheets as the cover board beneath the Impermitek waterproofing system. TechBoard's magnesium oxide composition provides a non-combustible, moisture-resistant, dimensionally stable and impact-resistant substrate for the waterproofing above it.

The application also marked the first use of ZS2 as a roofing product on an Alaska facility. Installation was completed in approximately 11 days by a five-person crew, with minimal onsite waste.

For a manufacturing plant designed around durable, high-performance building materials, the assembly reflects many of the same priorities: resilience, moisture management, sustainability, and long-term performance.

Precast Prototype Home:
Zs2 TechClad + Impermitek

Nearby, our Precast Prototype Home presented a different opportunity.

Unlike the ICF plant, the home was constructed from prestressed precast concrete components as a real-world demonstration of the building system APS is bringing to Alaska. That changed the needs of the roof assembly, particularly when it came to continuous insulation and thermal bridging.

Here, we used ZS2 TechClad™, a 6-1/2-inch assembly consisting of 1/2-inch TechBoard® over 6 inches of Type II EPS insulation, providing R-27 continuous insulation beneath the Impermitek waterproofing system.

Continuous insulation is particularly valuable in Alaska. Instead of allowing structural transitions to repeatedly interrupt the thermal layer, the insulation extends across the roof assembly to reduce thermal bridging and maintain more consistent thermal performance. ZS2 specifically designed the assembly around the demands of Arctic freeze-thaw conditions.

A five-person crew installed the roof assembly in five days, with very little onsite waste—a natural fit with a precast building system designed around planned, packaged scopes of work rather than layers of conventional field construction.

Why Pair ZS2 With Impermitek?

The value of the roof assembly comes from how its components work together.

ZS2 provides the durable layer beneath the waterproofing system. In the residential TechClad assembly, it also allows the roof to incorporate continuous EPS insulation into a coordinated package. Impermitek provides the waterproofing system protecting the assembly above.

For APS, several considerations made that combination particularly attractive:

• Moisture resistance: ZS2's MgO products provide a moisture-resistant substrate beneath the waterproofing layer.

• Dimensional stability: A stable cover board provides a consistent surface for the roofing system despite Alaska's demanding temperature conditions.

• Fire performance: Non-combustible TechBoard contributes to a more resilient roof assembly.

• Continuous insulation:At the Precast Prototype Home, the TechClad assembly provides R-27 continuous insulation while reducing thermal bridging.

• Durability:The system supports the same long-term objective that drives our approach to precast—building assemblies selected for demanding conditions and long service life.

• System compatibility:TechBoard provides the substrate for the selected Impermitek waterproofing and coating system, allowing the individual layers to work together as a complete assembly.

Building Beyond the Structure

For APS, developing a better building system isn't simply about manufacturing precast concrete. It's also about identifying complementary materials that can improve the performance of the complete building envelope.

The Manufacturing Plant gives us the opportunity to put these technologies to work at industrial scale, while the Precast Prototype Home demonstrates how they can be configured differently around a precast residential structure.

In both applications, the objective is the same: combine durable structural systems with envelope materials selected for Alaska's climate and the long-term performance we expect from the buildings we construct.

Bring High-Performance Materials to Your Next Project

Interested in incorporating ZS2 or Impermitek into your own project? Alaska Concrete Solutions (ACS), our sister company, is the Alaska distributor for both product lines, providing local access and support for projects statewide.

Learn more at ConcreteAK.com.