Building High-Performance Homes, One Triple-Pane Window at a Time
When it comes to designing homes that are as beautiful as they are efficient, Sustainable 9 Design + Build has become a leader in Minnesota. Known for modern design, attention to detail, and uncompromising quality, Sustainable 9 makes triple-pane, high-performance windows a standard across all their homes.
Steve Sylvestre, Initiative Manager at the Wise Window Hub, sat down with Paul Trieu, Director of Architectural Design + Engineering at Sustainable 9, to learn why triple-pane windows matter and why the industry should follow their lead.
Design with Purpose
Steve Sylvestre: Paul, tell us a little about Sustainable 9’s mission and what sets your homes apart.
Paul Trieu: Our mission is to design and build high-performance homes with a low carbon footprint that are architecturally distinct, locally sourced, and crafted with care. Every decision reflects our clients’ values: health, sustainability, and transparency.
Steve: You’ve made triple-pane windows standard in all your homes. How did that decision come about?
Paul: Windows are often the weakest point in a building envelope. Initially, triple-pane was just an upgrade we offered. But over time, the benefits such as comfort, efficiency, aesthetics, became too important to leave optional. Making them standard was a natural evolution.
“Once people experience the difference through consistent temperatures and quieter interiors, it becomes an easy sell.”
Windows as a Key Component
Steve: How do windows fit into your overall approach to building high-performance homes?
Paul: They’re critical, especially with modern homes that feature large glass areas. The more glass you use, the more performance matters, not just for energy efficiency, but for comfort.
Steve: Why choose triple-pane over double-pane?
Paul: Triple-pane windows deliver about 30% better performance than double-pane. When 30% of your exterior walls are windows, that’s roughly a 10% gain in overall envelope performance: a smart investment in both comfort and energy savings.
Steve: How do you weigh window upgrades against other envelope improvements?
"We look at the building envelope holistically, but windows are often the first place to upgrade. Since they’re the weakest performing element, improving them first gives you the most impact."
Talking to Homeowners
Steve: Do clients ever push back on triple-pane windows?
Paul: Absolutely, but we tackle it with education. We explain the long-term benefits like comfort, efficiency, resale value. Once they feel the difference, the decision becomes simple.
Steve: Which benefits resonate most with homeowners?
Paul: Comfort. Performance specs matter, but experiencing even temperatures and quiet interiors is what really sells it.
Steve: How aware are homeowners about triple-pane windows?
Paul: Awareness is growing, but adoption is still largely builder-led. Once we explain the advantages, clients get excited to be early adopters and help move the market forward.
INSERT LNBL comfort graphic (updated with accreditation)
“Stop focusing on upfront cost and start thinking about what you’re leaving on the table.”
On the Ground: Installation and Sourcing
Steve: How has sourcing triple-pane windows changed over time?
Paul: Initially, options were limited. Today, we rely on trusted partners like our local dealer, DWELL44.
Shaping the Future of High-Performance Homes
Steve: What would help make high-performance windows the industry norm?
Paul: Stronger energy codes, especially in colder climates, and more education. Awareness drives demand, and stricter standards accelerate adoption.
Steve: Any advice for builders hesitant to switch to triple-pane?
Paul: Focus on value, not just cost. Triple-pane windows deliver comfort, performance, and long-term value. A recent LBNL study shows that upgrading from double to triple-pane windows can decrease the heat pump tonnage needed by 1-2 tons for a typical electrically heated northern climate home. Highlight the opportunities for meaningful upgrades - that’s what clients remember.
About Sustainable 9 Design + Build
Based in Minnesota, Sustainable 9 Design + Build creates architecturally distinct, high-performance homes that balance modern design with superior comfort and efficiency. Their commitment to triple-pane, high-performance windows reflects a belief that is shared with the Wise Window Hub: building better homes should be the standard, not the exception.