About Deep Green

~ Serving Northern California Since 1997 ~


Dan Maupin-Ahern

CEO & Founder

I have been involved in residential construction for the majority of my life. My father was in the heating business and as a child I was his helper. As I got older, I was employed by a family friend who was a general contractor and became my mentor.

As a heating contractor in Massachusetts, my father was keenly aware of energy efficiency and inefficiencies. My home was a laboratory for his “experiments,” so to speak, and I grew up with a clear understanding of how to make houses comfortable. My fathers interest in heating technologies transferred to me as well. While I was in grade school during the early 1980’s, I created a solar hot water collector for the school’s science fair, showing how passive hot water heating works.

I got deeply involved with green building around 2005, as I became more aware of climate change and it’s devastating effects. Around that time I was introduced to the use of straw bales as insulation, as well as a great natural building material. I took a couple of workshops at the California Straw Bale Association (CASBA) and trained at UC Davis in sustainable building and design. It was at this point that I began shifting my focus away from traditional, environmentally unsustainable building methods.

I have been a licensed General contractor since 1997 and I have been working in Sonoma, Lake, Mendocino and Napa counties. In that time, I have been building houses from foundation to finish as well as doing many remodels and various home improvements. When the fires here in Northern California began getting worse (a result of environmental mismanagement and climate change), there was a sudden demand for new homes. This tremendous tragedy and loss opened my eyes to what my community was severely lacking: fire resistant, green, and sustainable construction.

We will not only build you a house, but together, we will help fight climate change.


Rich Rewerts

CFO / Owner

As a third generation tradesperson (two electricians and a carpenter) I have been involved with building projects since I was a teenager. I became a journeyman carpenter in 1996 while I lived in the Chicago, Illinois area where I worked on multiple projects. In the suburbs those projects included everything from new construction of single-family homes and townhomes to outbuildings, decks, and garages. In the heart of the big city, I was remodeling offices and other commercial spaces.

My wife and I settled in Sonoma County, California in the late 1990’s, where we raised our two children. Once in northern California, I began to learn new, environmentally friendly methods and the importance of the green building movement. I conducted many hours of personal research on healthier building material alternatives, which I put to use when I built my own home in the mid 2000’s. I became a licensed contractor in 2005.

Thankfully, much has improved in California building practices from then til now, and I am excited to be part of a company whose goal is to be mindful of the newest alternatives available and to build homes with an eye toward using less trees and providing non-toxic, green homes to protect the environment, as well as the people living inside of them.

Dan and Rich have worked together on projects as far back as 2003. In 2020 they finally decided to join forces and be business partners. Together, they each bring a wide and varied set of skills to the business which makes Deep Green Building unique, as well as fully adept for any type of project that comes their way.

Get in Touch

We would love to hear from you about what matters most for your home.

Give us a call at (707) 350-2490 or use our contact form.

Some of the North Bay areas we do work in are; Santa Rosa, Sebastopol, Windsor, Healdsburg, Forrestville, Kenwood, Glen Ellen, St. Helena, Napa, Calistoga

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