A Financial Approach to a Net Zero and Hurricane Proof Retrofit
Last Updated: Mar 10, 2025After a career that has included designing solar-energy systems and energy-efficient lighting systems; starting his own company, ShineRetrofits, which he built up and sold; and working in eCommerce, real estate investing, and finance, entrepreneur Erin Shine had an idea:
Table of Contents
- How Much Does it Cost to Live in a Net Zero Home?
- A Remarkable Retrofit
- Advice to Homeowners
Let's prove you can sustainably and attainably build houses that are actually affordable for first-time homebuyers.
His first project, a retrofit and remodel of a 1984 wood-frame home in the Cape Coral area of Florida, proves just that. After pouring through MLS listing in cities throughout the US, he says that community was his best option. He grew up in the area, still has family there, and knows the real estate market. Also, the house had a perfect roof for a solar array.
"It was an experiment to see if it would work," he says. "I'm in my mid-30s. Half of my successful professional friends still can't buy a house." In Cape Coral, Shine purchased the 1,835-square-foot, three-bedroom, three-bath house for $199,900. His project costs were $84,357.14. The total amount spent, then, was $284,257.14. For reference, the median home price for this area is $318,301.
Shine's solar-powered, all-electric, net-zero, and hurricane-resistant home is now his primary residence. He also started a new company, Attainable Home, to showcase the home and grow the home retrofit business to be more sustainable.
For Shine, the process of retrofitting a home to be more sustainable was all about numbers. Using a spreadsheet, he analyzed the upfront and payback costs of every upgrade. Why? "Real estate is the number-one wealth-building vehicle," he says. "Attainable Home is about how we can remodel homes realistically and affordably."
How Much Does it Cost to Live in a Net Zero Home?
The home's 9.38kw solar-powered system has 24 panels and micro-inverters. The panels are also "the highest-rated ones I could find for hurricane resistance." The array powers not only the home but also Shine's Tesla. Shine calculates that he's saving $1,800 a year in electricity costs, and $592 a year in gas, for a total yearly electric and gas savings of $2,392.
- The mortgage payment, after a 20% downpayment and an interest rate of 2.99%, is $926.34 per month.
- His property tax payment per month is $95.98.
- Homeowner's insurance per month is $147.17.
- The water bill is $85 per month.
- The monthly utility solar net-metering hookup fee ("even if you're net-zero") is $21.69.
- The home has also budgeted $1,000 per year for maintenance ($83 per month).
So, the total monthly cost to own the house, then, he says, is $1,359.18.
Camille LeFevre
Camille LeFevre is an architecture and design writer based in the Twin Cities.