Home Green Homes

In this conversation, Hoa shares her journey of finding and living in a cohousing community, Corvidae Co-op, highlighting the importance of community, sustainability, and the unique living experience it offers. The discussion delves into the motivations behind choosing cohousing, the features of the community, and the dynamics of living closely with neighbors — from shared kitchens and community dinners to the resale process and the emotional work that healthy community living requires.

Takeaways

• Cohousing fosters deeper, more intergenerational connections than a typical neighborhood
• Sustainability was a priority, but community was the primary driver
• Green features — solar, EV charging, all-electric, heat pumps — came built-in, not bolted on later
• Resale follows a structured process: first right of refusal to the seller’s pick, then the community, then the open market
• Community building takes real emotional work — conflict included — but that’s part of the benefit, not separate from it

Chapters

• 00:00 Introduction to Co-op Living
• 02:54 Motivations for Choosing Co-housing
• 05:36 The Unique Process of Co-housing
• 08:43 Exploring Covidae Co-op Community
• 11:56 Living in a Sustainable Environment
• 14:54 Challenges and Rewards of Community Living
• 16:03 Building Relationships in Co-Housing
• 17:11 Resale Processes and Community Dynamics
• 19:24 Evolving Community Structures
• 20:43 The Concept of Green Life Score
• 22:14 Environmental Consciousness in Co-Housing
• 24:17 Future Aspirations for Co-Housing
• 26:41 Creating a Legacy in Community Living
• 27:49 Exploring Airbnb and Community Engagement

Links:

• Corvidae Co-op: frolic.community/projects/corvidae-co-op
• Frolic Community: frolic.community
• Green Canopy NODE: greencanopynode.com
• National Cohousing Alliance: cohousingalliance.org
• Contact Corvidae: [email protected]
• Airbnb listing: Covidae Co-op AirBnB
• Contact: [email protected]

Most home tours happen on move-in day, when everything's shiny and nobody's tested anything yet. This one is different — Bill Spohn and his wife built a net-zero, airtight, modular "Pretty Good House" outside Pittsburgh, and they've lived in it for six years.

So what actually happened? A factory installation mistake led to a rotted subfloor and — yes — mushrooms growing under the shower. Two windows still won't seal in winter (there's blue painter's tape involved). The AC failed once from a bad install, not a bad heat pump. And yet Bill says he's more pleased with the house now than the day they moved in — quiet, comfortable, and still net-zero on an annual basis.

We talk about what six years of real living reveals that a spec sheet never will: the honest tradeoffs of going airtight, why he skipped a battery backup, the well and septic saga that almost derailed the build, and what he'd actually tell someone considering this path today.

Bill also runs BetterHVAC.org, a free nonprofit directory connecting homeowners with contractors who understand building science — not just HVAC in isolation.

Resources mentioned:

• spohnhome.com — Bill's build story and blog
• betterhvac.org — free contractor directory
• trutechtools.com — Bill's business, home performance testing tools
• Building Performance Institute — credentialing body for home performance contractors
• Solar United Neighbors — nonprofit that runs local solar co-ops to help homeowners get better group pricing

Timestamps:
00:00 Introduction
00:31 Bill's background and motivation
02:06 The concept of passive house
03:04 Designing for energy efficiency
04:51 Achieving airtightness
06:17 Ventilation solutions
10:29 Challenges in construction
12:53 Achieving net-zero energy
17:07 Living in the home
20:16 Tips for building energy-efficient homes

David Gottfried — often called the godfather of the green building movement — co-founded the U.S. Green Building Council in 1993 and the World Green Building Council in 1998. He's the author of four books, including his newest, Regen360, and he joins the show to talk about something more personal than LEED scorecards: what it actually took to green his own homes, and what he wishes more buyers, sellers, and flippers understood.

We talk about the 1930s Craftsman kit home in Berkeley he renovated into one of the highest-scoring LEED Platinum homes in the world — the rainwater-fed toilet that ran dry mid-dinner-party, the graywater pump he had to relocate out from under the master bedroom, and the acoustics mistake that eventually pushed him to sell. We get into why that house didn't sell for the premium he expected, what he did differently in the homes that came after, and his direct response to investors who tell him going green adds "50% more" to a renovation budget.

David also unpacks the equation at the center of his new book: HOPE — Health On Planet Earth — and why he believes a home that doesn't "accelerate hope" simply isn't worth as much, no matter what the flipper is asking.

In this episode:

• The pivot from real estate developer to founder of the green building movement
• Inside the Berkeley Craftsman renovation — the wins, the mishaps, and the acoustics regret
• Why the house didn't get the resale premium he expected, and what that taught him
• Debunking the "50% more expensive" myth flippers use to avoid going green
• What role certifications like LEED actually play in home value
• The HOPE equation — Health On Planet Earth — and what it means for the home you're buying or selling
• His message to the next generation inheriting what we've built

What's your biggest challenge with sustainable living? Drop it in the comments!

Subscribe for more insights on green building and sustainability!

#GreenBuilding #Sustainability #ClimateAction

Sustainability alone won't protect your home from Mother Nature. In this episode, Izumi Tanaka talks with Albert Slap — environmental attorney turned founder of RiskFootprint.com — about why resilience and sustainability are two sides of the same coin. Albert breaks down why FEMA flood maps miss huge amounts of real flood risk (120,000 homes flooded outside the FEMA zone during Hurricane Harvey), why he pays $5,000/year just for hurricane wind coverage on his own home, and how a $5,000 roof-to-wall tie-down saved him from a $30,000 re-roof — and actually lowered his risk. We also get into wildfire vegetation management, the 34+ natural hazards RiskFootprint evaluates property-by-property, and why "caveat emptor" due diligence should start well before you sign an agreement of sale. Whether you're buying, selling, or staying put, this episode is a reminder that a green home and a resilient home are the same goal. 🔗 Learn more: https://riskfootprint.com

TIMESTAMPS

00:00 Intro: sustainability + resilience, two sides of one coin

01:20 Albert's pivot from environmental law to RiskFootprint

02:59 What "caveat emptor" really means for buyers

05:32 Why FEMA flood maps don't capture rainfall flooding

07:19 Albert's own $5,000/year hurricane wind insurance bill

12:10 The roof-to-wall tie-down that saved $25K

16:54 How RiskFootprint evaluates 34+ natural hazards by address

23:39 Who actually uses RiskFootprint: buyers, realtors, lenders

28:16 Disclosure laws: Hawaii, Florida, Colorado and beyond

29:04 Climate trends vs. day-to-day natural hazard risk

34:25 Where to find RiskFootprint.com Home Green Homes is a podcast about the people building — and buying — greener, more resilient homes.

#HomeGreenHomes #GreenBuilding #ClimateResilience #RealEstate #SustainableLiving

What does it actually look like to flip a house the green way — and make the numbers work?

In this episode, Izumi sits down with Mary Love, a North Carolina-based green realtor, building scientist, and project manager who has been doing eco-conscious real estate investment long before "green homes" was a mainstream term. Mary shares hard-won lessons from decades of rehabbing and renting energy-efficient properties — from wrangling reluctant HVAC contractors to educating appraisers on the value of sustainable upgrades.

In this episode, you'll learn:

• Why insulation and air sealing are always the first priority — and how to do it without gutting the walls
• How to use blower door and duct blaster tests to document before and after performance (and use it as a marketing tool)
• What appraisers actually need to see to give green upgrades their proper value
• How rebates and incentives can make eco-flipping cost-competitive with standard rehabs
• Why the conversation has shifted from energy savings to safety and resilience — and what that means for investors
• The "Fortified Standards" framework for disaster-resilient construction
• Mary's motto: "A little bit of something is better than a whole lot of nothing"

Whether you're a seasoned investor or just starting to think about greener rehabs, Mary's practical, no-nonsense approach will show you that eco-flipping isn't just good for the planet — it's a smart business model.

📬 Connect with Mary Love: [email protected] | lovethegreen.org

Are homes really built to last… or just built to sell?

In this eye-opening episode, Izumi sits down with documentary filmmaker George Siegal, creator of Built to Last: Buyer Beware, to uncover the uncomfortable truth about how most homes are actually built—and why so many fail when disaster strikes.

From hurricanes in Florida to wildfires in California, George shares heartbreaking stories of homeowners who lost everything—and the common patterns behind those losses. The biggest takeaway? Most homes are built to the minimum code, not for long-term resilience.

If you’re a homeowner, buyer, investor, or real estate professional, this conversation may completely change how you look at homes.

• Why “built to code” often means built to the bare minimum
• The biggest mistakes homebuyers make when evaluating a property
• How disasters reveal hidden weaknesses in our homes
• Why rebuilding after a disaster can take years—not months
• The surprising connection between resilience and sustainability
• What questions you must ask before buying or building a home
• How insurance, building practices, and human behavior all play a role

George also shares practical tips—including how one simple correction saved him $1,000/year on insurance—and why homeowners need to take responsibility for understanding the true quality of their homes.

🎬 Watch the film: Built to Last: Buyer Beware
📄 Free resource: Essential questions to ask before buying a home

Bottom line:
Don’t just fall in love with the finishes—the countertops, the floors, the “wow” factor.
Understand the bones of the house… because that’s what determines whether it survives.

In this episode of Home Green Homes, Izumi Tanaka talks with Nick Grimm — a father, homeowner, and sustainability professional who is gradually transforming his 1953 Los Angeles home into a healthier and more energy-efficient space.

Nick didn’t begin with a master sustainability plan. Like many homeowners, his journey started with basic maintenance: replacing appliances when they broke and making upgrades when necessary. But as he learned more about sustainability, each decision became an opportunity to choose better options.

So far, Nick and his family have:

• Replaced a gas cooktop with an induction stove
• Installed a heat pump washer/dryer
• Upgraded their electric panel
• Installed solar panels
• Purchased an EV and charger
• Begun planning for heat pump HVAC and water heating
• Started thinking about drought-resilient landscaping

One turning point came when Nick used an indoor air quality monitor while cooking on a gas stove — and saw pollution levels spike inside his home. With a young child experiencing asthma, it accelerated their switch to induction cooking.

Nick also discusses the real barriers to electrification, including the complexity of rebates and the financial realities many homeowners face.

Despite those challenges, he believes individual choices still matter. For Nick, the ability to take action — even one appliance at a time — is empowering.

If you're a homeowner wondering whether it’s time to replace gas appliances with electric alternatives — this episode is for you.

In Episode 102 of Home Green Homes, Izumi chats with Akanksha Mathur, General Manager for Southern California at Elephant Energy, to discuss what it really takes to electrify your home.

From heat pumps and induction cooking to rebates, incentives, and indoor air quality — we break down the electrification process step-by-step.

Elephant Energy is a Certified B-Corp focused on making the switch from gas to electric simple, seamless, and climate-friendly. Akanksha shares her journey from mechanical engineer to climate advocate, and why education is the missing link in helping homeowners make confident decisions.

If you live in Southern California — or anywhere thinking about clean energy upgrades — this conversation will help you understand:

• What “home electrification” actually means
• How heat pumps work
• What incentives are available
• Why indoor air quality matters
• The biggest challenges homeowners face
• How to make sustainable choices easier

The future is electric. The question is — are you ready?

🎧 Listen now and learn how to make your home cleaner, healthier, and more energy-efficient.

Chapters

00:00 Introduction to Elephant Energy

05:19 Akanksha's Journey to Elephant Energy

10:15 The Process of Electrification

15:44 Challenges in the Electrification Process

20:59 Educating Homeowners on Electrification

26:16 Personal Reflections and Future Aspirations

More Resources:

• Switch-is On
• TECH Clean California

What does it really take to build homes that are beautiful, efficient, resilient, and responsible?

In this special 100th episode of Home Green Homes, Izumi Tanaka welcomes Steve Glenn, founder and CEO of Plant Prefab, for an in-depth conversation that weaves together architecture, sustainability, entrepreneurship, and climate action.

Steve traces his path from an early love of architecture to founding LivingHomes and later Plant Prefab—companies created to challenge the waste, inefficiency, and environmental impact of conventional construction. He explains what truly sets Plant Prefab apart: customized architectural design, a purpose-built factory capable of both panelized and modular construction, and a mission-driven commitment as a certified B Corp and public benefit corporation.

The conversation also dives into Plant Prefab’s work supporting communities rebuilding after devastating Southern California wildfires, and why prefab construction can offer faster, more predictable, and often more cost-effective rebuilding solutions.

Along the way, Steve addresses common misconceptions about prefab homes, shares what homeowners should prioritize when designing for climate resilience, and reflects on leadership, scaling a values-driven company, and what he hopes the future of housing can become.

This episode is especially relevant for homeowners, home dwellers, architects, builders, developers, and anyone curious about how housing can be part of the climate solution.

• Prefab ≠ mobile homes: Plant Prefab homes are legally and structurally equivalent to site-built homes and cannot be excluded from zoning, financing, or insurance.
• Energy matters most: Over a home’s lifetime, operational energy use has a bigger climate impact than materials—efficiency and solar should be top priorities.
• Time is money: Faster, parallel construction can significantly reduce carrying costs, rent, and uncertainty—especially important in rebuild scenarios.
• Design and sustainability go together: High-quality architecture and environmental responsibility are not mutually exclusive.
• Rebuilding after disaster is an opportunity: Prefab can help communities recover faster while building more resilient, future-ready homes.
• Mission-driven businesses face real challenges: Scaling sustainably takes persistence, patience, and long-term vision—but the impact compounds over time.

Chapters

• 00:00 Personal Impact and Vision for the Future

“So when I think about a future that is solving climate, I think about raising our quality of life. I think about more inclusive cities with wonderful parks, and it's a fantastic mass transportation that's really considered a luxury good because whether you're the wealthiest person in that city or the poorest, you all want to be on the same subway or the same bus because it's simply the best way to get around and everyone enjoys these types of amenities.There are examples of that all over the world.  We try and bring those to light. And that is my vision for what the future starts to look like.”

Josh Dorfman spent time in China in the 1990s, which opened his eyes to  environmental issues and the impact of rapid industrialization and consumerism. When he returned to the U.S. and went through a phase of environmental activism before deciding to focus on shifting consumption towards more sustainable products.  He started an eco-friendly furniture company called VivaVie in 2004, which led to the creation of his "Lazy Environmentalist" media brand.

During the pandemic when supply chain issues made it difficult to source sustainable materials for his previous furniture company, he developed Planted - Josh's current carbon-negative building materials company.  They identified fast-growing perennial grass as a potential replacement for traditional lumber and engineered wood products.  They worked to vertically integrate the entire supply chain, from growing the grass to manufacturing the building panels, and partnered with major homebuilder D.R. Horton to secure a large order for their carbon-negative panels.

Josh then launched a media company, Supercool, after stepping down as CEO of Planted to focus on sharing stories of climate innovation and solutions.  Supercool aims to highlight commercialized, scalable technologies and initiatives that are improving people's lives while addressing environmental challenges. He shares his vision for a "Supercool future" that involves raising quality of life through inclusive, sustainable cities and infrastructure.