Our Practices

O&N has been on the forefront of mass timber construction on the east coast, pioneering the use of mass timber in multiple projects, including 675 E. Swedesford Road and Swarthmore College’s Sharples Dining Hall & Community Commons. Our most recent project, Ellis Preserve’s Mass Timber Office Building, is the region’s first commercial structure to offer this entirely sustainable technique for general office use.

Our President Dennis Mordan is a nationally recognized thought leader dedicated to spreading awareness of mass timber’s enormous sustainability and cost-efficiency benefits. He, and others at O&N, regularly present O&N’s AIA-accredited “Mass Timber 101” program and have worked with groups like the Wood Council to increase education and excitement about its use.

Dennis has recently been featured in Civil + Structural Engineer magazine, speaking to the benefits of Mass Timber construction.

Part 1 Part 2

O&N is also a proponent of low carbon concrete, which is produced with a lower carbon footprint than that of traditional concrete. Other than a reduced carbon footprint, lower carbon concrete behaves identically to its standard concrete counterpart. To create lower carbon concrete, we implement a series of relatively low-impact changes to the mix designs; replacing some cement content with mineral compounds like calcined clays, fly ash or blast-furnace slag, or using Portland Limestone Cement (PLC) instead of conventional Portland Cement.

The adaptive reuse of buildings stands as a cornerstone of sustainability practices, embodying the essence of environmental responsibility and resource conservation. O’Donnell & Naccarato’s engineering services have been integral in the repurposing of hundreds of existing structures of all types. Instead of demolishing and rebuilding, adaptive reuse minimizes waste generation and reduces the consumption of new materials – significantly lowering the environmental impact associated with construction and preserving embodied energy and materials already invested in the building. It breathes new life into neglected or underutilized spaces, promoting revitalization within communities while simultaneously curbing urban sprawl. Adaptive reuse preserves historical and architectural heritage, fostering a sense of continuity and cultural identity within neighborhoods. Beyond environmental benefits, it offers economic advantages by lowering costs associated with new construction while stimulating job creation through renovation projects. Ultimately, adaptive reuse champions sustainability by promoting responsible stewardship of resources and embracing the inherent value embedded in existing built environments.