02 | Multifamily Build SMART | Capital Flats

Energy Efficiency made Simple

Capital Flats: Phase 3, The Battery

Experience the remarkable Capital Flats: Phase 3 – The Battery, a visionary project completed in 2017. This groundbreaking development is the result of a remarkable collaboration with Build SMART, unlocking new possibilities in attainable and sustainable market-rate housing. In response to a fully gentrified neighborhood becoming increasingly homogeneous, Phase 3 takes a bold step towards balance and equity.

Through the innovative Build SMART System, this four-story Zero EnergyREADY building has been meticulously crafted to deliver exceptional results. With 25 thoughtfully designed units it sets a new standard for energy efficiency, consuming a staggering 80% less energy than traditional code-compliant buildings.

Build SMART’s revolutionary approach ensured that the Capital Flats: Phase 3 achieved unparalleled benefits for project teams. From its seamless assembly process to its impeccable tightness, the Build SMART System surpasses all expectations. Witness the transformative energy qualities that have left industry experts astounded.

Join us in celebrating the testimony of the President and Vice President of Onion Flats, who both hail the Build SMART System as the pinnacle of excellence.

Discover how this collaboration has brought forth an architectural marvel that offers unique advantages to project teams. Explore the extraordinary achievements of Capital Flats and the remarkable Build SMART System.

“Hey man, listen. The Build SMART System is beautiful! The way it goes together, the way it’s tight, the energy qualities of it. It’s the best system I’ve ever seen in my life. – Patrick McDonald, Vice President of Onion Flats



Philadelphia, PA

Project Type



25 units, 20,000 square feet

Cost per Square Foot


Air Changes Per Hour

0.046 cfm50/ft2

Project Profile Sheet

Onion Flats works with Build SMART

Onion Flats construction  commercial project

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More about Capital Flats

“When you select Build SMART to supply your next project, you’re not settling for just another producer of prefabricated ‘Wall Panels.’ We do much more than cut and nail your framing together. Build SMART is an off-site extension of your entire build team.”

– David Boyer, President/CEO


The Build SMART Difference


The beauty of Build SMART Prefab

“With the Build SMART System, everybody is an expert, everybody can build high performance buildings. That’s how we change the scale, that’s how we change the industry.”


Panelized Multifamily Whitepaper