Deep Energy Retrofit – Energy Neutral Remodeling

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Staying in this house was never in the plan.  We’d hoped to move into this little house in town for a couple of years, remodel and flip it, and then move to the country to live “off the grid.”  But then it happened.  We fell in love.  Not only with our “little blue house,” but also with all that town life had to offer.

Walking the kids to school, biking to the farmers’ market, walking up-town to attend a lecture or a concert at the University.  Not to mention the high-speed internet access that let us work at home.  After watching many of the “country families” spend hours in the car each day commuting to town for work, school, activities, and socializing, town life was becoming very appealing.  But we had a problem. 

The “little blue house” was a leaky, rotting sieve.  Not only was it hard to heat in the winter and hard to cool in the summer, but humidity levels were either unbearably dry or damp, depending on the season.  No matter how much we spent on energy bills, we weren’t comfortable.  How could we “live” with this house into the future?  We’d already “weatherized” the house in many, small ways.  We’d even added blown-in cellulose insulation to the walls and attic.  Still, the house performed miserably.  We could only keep the energy costs down due to its size – 1000 sq ft.  There had to be a better way.

der1Ever since I helped my Dad build the passive solar home I grew up in, I’ve hoped to build my own brand new “green” home.  With 25 years in the building industry under my belt, I’d never lost sight of that goal, keeping my finger on whatever green building techniques and products were out there.  We’d gone as far as buying the land in the Ohio Appalachian hills where we hoped to settle, but now the whole plan had changed.

Then it occurred to me that we weren’t the only homeowners facing these problems.  There had to be a way to address all of the issues of owning an older home.  A way to bring it into the 21st century and make it work into the future.  A way to incorporate the best of new green building, but preserve our location and our very rich, green town life.  Enter the Deep Energy Retrofit.

A Deep Energy Retrofit is a process that attacks every aspect of an older home’s energy use, scrutinizing it and maximizing energy savings at every turn.  Then, once the home has cut its energy use by 50%-90%, renewable energy is added for a very powerful one-two punch. 

We started with a HERS home energy audit done by Andrew Frowine from SaveGreenUSA.  Andrew gathered data about our building envelope, including insulation, window types and sizes, and many more details.  Then he performed several tests, including a blower door test to determine just how leaky our home was, a duct blaster test to determine the state of our HVAC ductwork, and thermal imaging to actually “see” where our home leaked energy.  Andrew turned all of the data into a detailed report, which helped us decide how to design our DER.

der2Our plan?  To attack the leaky building envelope using a “curtain wall” approach.  On the old roof and exterior walls we added 2x3 studs, on edge, with 4” screws directly over the old siding and roof shingles.  Then we sprayed “do-it-yourself” spray foam insulation into the cavities.  After that, we installed sheathing, house wrap, and engineered wood siding and trim on the walls, and radiant barrier sheathing, underlayment, and a combination of recycled rubber faux slate shingles and white rubber membrane on the roof.  Then we replaced all of the old rotting, single-pane windows with triple-pane, krypton gas filled models.  The old wooden doors were replaced with insulated fiberglass doors.  We replaced the rotting garage with a slightly larger, super-insulated structure with an insulated slab foundation.  All of the envelope improvements gave us R-30 walls and an R-50+ roof, all completely air-sealed with the expanding spray-foam insulation.

With the house so tight, we installed an Energy Recovery Ventilator, which exhausts dirty stale indoor air and brings in fresh outdoor air while keeping 95% of the energy we’ve used to heat or cool that air inside the house.  The ERV gives us healthier, more comfortable indoor air quality without losing energy to the outdoors.

Over time we had been replacing our appliances as they failed.  We now use a front-loading washer, high-efficiency dishwasher, tankless water heater, and Energy Star or better appliances everywhere else.  As incandescent lights had failed, we’d replaced them with CF and LED lighting.  Every little bit counts, and our “little bits” were adding up.

Since we’d “eaten our vegetables” by attacking our energy efficiency, we were able to “have dessert” in the form of solar energy.  We took advantage of renewable energy incentives at the Federal & State level to add a 4kW solar array to produce nearly all of our electricity.  In addition, by selling the “SRECs” (Solar Renewable Energy Credits) to a regional broker, we were able to bring the cost of the system down from $32,000 to $8,000 – the system will easily pay for itself in under 10 years.

The result?  Even with the DER only about 70% complete, we cut our heating costs by 2/3 last winter – even though we had the coldest winter in years AND I turned up the heat to 70F to keep us more comfortable in our super-tight house.  Our electric bills are small or non-existent, and we get credits from our grid-tied system during the summer months.  And if energy prices rise?  We’re covered.

In the coming months, we’ll be adding the curtain wall process to the interior of our basement walls and floor, and adding solar-thermal air heaters.  We’ll also be finishing off the interior of the addition space with low-impact building materials like local hand-made tile and sustainably harvested, local hardwood floors.  And we won’t stop until we’re net-zero for our home and transportation, so we’ll be Deep Energy Retrofitting for some time to come.

All of this, and we’re helping to combat many of the biggest problems of our time – we put local construction workers to work on the framing, roofing, and drywall work, stimulating our local economy.  We also helped manufacturers of green building materials at a time when demand is low due to the housing crisis.  We’ve drastically reduced our carbon footprint.  And we’ve made our home ready for the plug-in hybrid revolution in the transportation sector, which will help reduce oil imports, strengthening our national security.

And now that we’ve settled in town, what’s happening with the land in the country?  We’re holding on to that.  Since we no longer plan to move there, we’ve enrolled it in several conservation programs.  We spend weekends clearing invasive species and helping to restore the Appalachian woodland and its bio-diversity.  I figure it also serves as a good 60-acre carbon sink for what fossil-fuel energy we have to use.

der3To see more about our DER process, check out  There you’ll find a blog and video series on the project, along with a growing list of DER resources.

With 25 years in the building industry, Jeff Wilson is also the host of nearly 200 episodes on the HGTV and diy networks, and the host of the HGTV Green Home 2011 video series on  He’s also the host of how-to and green video series on  Learn more about Jeff at  Look for Jeff’s book on his DER project, the Greened House effect, in late spring 2011.

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