M+K was invited to join the design team for a distinctive custom home project located in suburban Philadelphia, Pennsylvania. The client envisioned a modern, single-family residence that would house an extensive art collection while adhering to Passive House standards—minimizing the building’s carbon footprint and optimizing energy efficiency. The goal was to create a living
environment that balanced both the preservation needs of the artwork and the homeowner’s desire for sustainable comfort.

The design called for a 7,300 SF, 2-story modern home atop a precast concrete basement foundation, with large open interior spaces to showcase art. Structural engineering was integral in ensuring that the home’s thermal envelope was as airtight and energy-efficient as possible while still meeting the client’s aesthetic goals. This involved balancing the architect’s vision for large windows, cantilevered elements, and expansive spaces with the need for a stable, code-compliant structure capable of supporting the Passive House standards.

Passive House Engineering Integration

Passive House design presents unique structural engineering challenges—particularly when it comes to minimizing thermal bridging, reducing penetrations in the envelope, and integrating mechanical systems. Our team worked closely with the architect to incorporate deep wood-framed roof and floor trusses into the design. These trusses were specifically designed to accommodate the substantial mechanical systems required for Passive House construction, allowing for clean ceiling lines and avoiding dropped soffits—key to maintaining the sleek, modern aesthetic of the home.

Energy efficiency also introduced a need for meticulous coordination in the structural design to limit thermal envelope penetrations. By focusing on solutions that allowed for continuous insulation and airtightness, our engineers were able to avoid common issues associated with conventional structural designs. Special attention was paid to integration with exterior and interior insulation, as well as optimizing material efficiency in line with sustainability goals.

Innovative Wall Systems

A notable innovation in the project was the use of specialized, panelized wood-framed walls. These walls were more substantial than those in typical production construction to meet the strict energy performance requirements of Passive House design. Each panel was fabricated offsite using 2×8 studs, with exterior sheathing, insulation, and interior drywall pre-installed. The offsite construction approach required early collaboration between M+K and the panel manufacturer to ensure that load paths, lateral stability, and the structure’s airtightness were maintained before the panels were delivered to the site.

Lateral Design Challenges

One of the most complex aspects of the project was the large, elevated living room that projected from the main structure. Designed to take advantage of natural light year-round, the space featured floor-to-ceiling glass windows, eliminating the possibility of using conventional shear walls for lateral stability. Our team worked closely with the architect to design a custom 2-story steel
moment frame that met the lateral load requirements while preserving the clean architectural lines. The result was a seamless integration of structure and design, enhancing the modern look without compromising performance.

Conclusion

This project is a prime example of how structural engineering can play a pivotal role in bringing a Passive House vision to life. From minimizing thermal bridging to accommodating unique design elements like large windows and cantilevered structures, M+K helped to engineer a home that not only meets but exceeds the energy-efficient standards of Passive House. The result
is a sustainable, comfortable, and visually striking residence that fully supports the client’s goals of preserving art while reducing environmental impact.

We were honored to contribute to such a transformative project that demonstrates how innovative engineering can enable cutting-edge architectural design while maintaining a focus on sustainability.

Last August, fires tore through the heart of Lahaina, a town on Maui, HI, destroying thousands of homes and businesses and displacing nearly 6,000 residents. The fires were the deadliest in recent U.S. history, leaving a profound impact on the community. Rebuilding Lahaina has required a coordinated response from community leaders as well as construction and design firms. Much work remains, but a recent milestone has been achieved ahead of the stated 2025 goal—debris has been cleared from all 1,390 residential properties in the impact zone. This means that building permits—in addition to optimism—have been restored.

M+K has been working with WMC Design Build as well as PILI in separate but coordinated efforts to provide structural designs for the rebuild. This is our first effort in Hawaii and one that we are all very proud of being able to contribute to. One of PILI’s contributions is creating pre-designed plans that are being offered to wildfire-affected homeowners, while WMC Design Build has been working on plans that are budget-conscious while still being bespoke and thoughtfully curated.

(Above: WMC Design Build renderings)

“Our work with Mulhern + Kulp has been tremendously impactful; they have provided us and our families with tremendous value through construction savings, peace of mind, cohesive design, among the few that pop to mind. Their flexibility and ability to work within our parameters, in addition to their responsiveness and diligence, has made our collaboration seamless. Their capacity to support our projects with cost-effective and quality design enable us to provide safe, high-quality housing to families in need, aligning with our mission to deliver impactful solutions. By integrating the expertise of Mulhern + Kulp, we aim to rebuild not just homes, but also hope and resilience within the community.” said WMC Design Build Program Manager, Jordan Haylor.

“At PILI, we’ve been fortunate to collaborate closely with Mulhern + Kulp on our fire rebuild projects in Lahaina, Maui. This partnership has been instrumental in allowing us to extend our capacity as a small, Maui-based firm and respond to the significant demand for architectural services following the disaster. M+K’s ability to provide detailed structural engineering plans and calculations ensures that we can confidently submit permit documentation, meeting all requirements, which allows for expedited review and approval. Given their expertise and manpower, M+K can offer faster turnaround times, an invaluable asset in these critical rebuild efforts, especially as smaller local firms are facing an overwhelming workload,” said managing partner Brenda Braun.