02 | Multifamily Build SMART | Capital Flats

Energy Efficiency made Simple

Capital Flats: Phase 3, The Battery

Phase 3 of Capital Flats, completed in 2017, responded to the need for attainable and sustainable market-rate housing in a neighborhood now fully gentrified and increasingly more socially and economically homogenous. Phase 3 attempts to help balance that inequity by creating a four story, Zero EnergyREADY building, packed with 25 “micro-units”. The project is designed to consume 80% less energy than a similar code building.

“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.”

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