Stephen Runnels & Chuck Chippero
Large Production Builder
Pulte's panelized system is primarily installed in mid- to high-end developments with homes up to 6,000 square feet in Northern Virginia. A dozen of Pulte's large developments in the area are using unique panelized components manufactured in Pulte's Manassas, Virginia plant.
Faced with increasing shortages of skilled labor and the desire to create a market niche through high-performance homes, Pulte Homes made a long-term business decision to invest in innovation. This decision was based on years of internal research and a corporate mission to embrace innovative solutions.
A giant in the industry, Pulte invested significantly in manufacturing capacity to supply its new division, Pulte Home Sciences. From its panel factory, Pulte manufactures concrete foundations, open-web floor joists, structural insulated panel (SIP) external walls, and steel-framed interior walls to create energy-efficient, durable homes. Not every builder can replicate this investment, but any builder can apply Pulte's lessons learned.
Pulte manufactures and supplies factory-built components similar to those that are available from other manufacturers, but Pulte standardized the products by designing and building its own.
"The design and selection of the individual subsystems of our homes were carefully chosen to support our dedication to whole-house performance," says Chuck Chippero, General Manager of Pulte Home Sciences. "We developed individual subsystems that complemented each other from a structural, thermal, moisture management, and--very importantly--assembly standpoint. We deployed them all independently at first, and over time worked them into a full shell system. Our goal was to reduce the ultimate operating cost to the homeowner by providing them with a high-efficiency home."
Pulte sees many advantages of precast foundations and has developed some valuable installation procedures.
"We build our foundation in the factory out of a very dense, very high-yield strength concrete," says Stephen Runnels, director of Field Operations for Pulte Home Sciences in Virginia. "We use 5,000+ psi concrete, rather than the industry average of 3,000 psi, for on-site curing. This high density occurs because we pour it at a very long slump, so it's a very liquid pour that self-compacts. The high density in the concrete makes the foundation more water resilient, which is a benefit to the homeowner."
After shipping and installing the concrete panels, site workers apply a moisture curing urethane at the seams of the foundation.
"Because the inside of the urethane coating remains pliable, it functions like a gasket seal," says Runnels. "If ground movement occurs, the walls may move and in extreme cases may tear the skin of the urethane. When this happens, the urethane sealant skins over the seam again to maintain the seal. So you get a good gasket seal even if there is movement in the foundation.
We're talking minimum movement, but in conventional pour-in-place concrete foundations, it can lead to long-term problems like cracking, leaks, and bridging."