John Tabor, owner of Tabor Design Build, in Rockville, Md., put his money where his mouth is when he incorporated green elements into a three-story addition to his own home.
Now, after completing the remodel — one of the most complex projects his company has done — Tabor says he feels confident when talking with clients about the green practices he used. “I can tell them from personal experience,” he says.
In the remodel, Tabor used several practices that he had been wanting to try but couldn’t find clients willing to use: insulated concrete forms for the foundation, geothermal HVAC, and solar panels.
He hosted meetings so that his trade contractors could coordinate the installation schedule with each other. For example, his electrician had to map out the solar panel circuitry and coordinate with both the solar and geothermal subs. Also, Tabor’s supervisor had to manage all of the trades on site to make sure that they correctly installed their portion of the work.
Tabor says that even if you discuss details with the management or salesperson for a company, “it has to be confirmed with the people doing the actual work.” He found that larger subcontractors are more up to speed on these types of advanced technology.
Though some of Tabor’s customers have inquired about geothermal heat pumps, they have opted out due to the high up-front cost. Tabor thought that if he installed geothermal for his entire house while doing the addition, he could then convey his experience with the closed-loop system and prompt clients to use it. He met with several companies and chose Michael Bonsby Heating and Air Conditioning, which recommended Allied Well Drilling.
Rather than tear up his yard and landscaping, Tabor opted to drill three 450-foot-deep vertical wells, at a total cost of about $30,000, including all of the piping from the wells to the house. The only snag came when the drilling equipment hit rock at around 60 feet and started generating silty stone dust. As a precaution, Tabor had stapled a temporary fabric fence to wooden stakes to prevent any silty water from washing into the neighbor’s property. “It was not sufficient. We should have used a super silt fence,” Tabor says. He cleaned up the spillage and used it for backfill.
The total cost of the system, including the heat pump equipment and electrician’s costs was $88,000. Tabor will receive a 30% federal tax refund on the cost of the installation but must wait until he files his taxes to see the savings. He will also receive county and state rebates.
It has been almost a year since the system was installed, and Tabor says it provides a more comfortable environment because the air doesn’t feel as dry as with his gas furnace. The house is one-third larger, yet Tabor has lowered his heating and cooling bills by one-third.
Snug & Form
The basement of the addition stays warm in winter and cool in summer due to the insulated concrete form foundation.
Since Tabor already felt he was “doing enough experimenting,” he opted to start small with just the addition foundation, which gave him an opportunity to try ICFs without taking on a full foundation.
The QuadLock product he used interlocks much like Lego blocks. “There are tricks for how to rack them and how to brace them,” Tabor says. “They need to be put together in a certain order.” The resulting wall is “very strong, is well-insulated, and contributes to energy savings,” he says.
Tabor estimates the system cost twice as much as conventional steel forms, but points out that some of that is due to the learning curve. He says that with enough practice, the system will cost only about 50% more.
One of Tabor’s main goals with the addition was to create a south-facing roof where he could install solar panels. The 17 Sharp NU-U235F3 photovoltaic panels are clamped to the addition’s standing seam metal roof and are hooked up to an inverter connected to an electrical panel. “This provides some of the power to the house,” Tabor says. His subcontractor worked with a solar energy finance/development firm to set up the system so Tabor receives solar renewable energy credits for unused power. “I receive a check for a few hundred dollars every quarter,” he says.
Tabor’s installed cost was $30,000. As with the geothermal system, he is entitled to receive a 30% federal tax credit on the total cost of the solar energy system.
Taming the Energy Hog
Although Tabor’s house is just 12 years old, he describes it as an “energy hog.” As part of the remodel, he decided to super-insulate the attic in both the main house and the addition, the goal being to “enclose all the ductwork in the insulation.”
Subcontractor crews installed 4 feet of blown-in fiberglass — the most Tabor has ever specified. He considered spray foam insulation, but he would have had to remove the existing fiberglass to install it. He did use a 1-inch flash coat of spray foam to seal the walls in the addition and then added blown-in insulation. The cost of the insulation install: $5,000.
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Insulated Concrete Forms
—Nina Patel, senior editor, REMODELING.
REMODELING columnist and green consultant Carl Seville criticized the magazine’s coverage of this project in a blog he wrote for Green Building Advisor .
Seville says that the article focused on “bling” such as solar panels and a ground-source heat pump, and the high installation costs of these items, and he noted the lack of energy performance information.
We have updated the online version of this story to reflect the actual price of the geothermal system, which is $58,000.
Editorial director Sal Alfano responded to Seville’s blog and the subsequent comments posted on the Green Building Advisor site to clarify that REMODELING’s article “was never intended as a case study of a deep energy retrofit. It was a training ground with a marketing component, and that’s the story we chose to write. We included costs partly because there is a lot of speculation about the cost of renewables but not many hard numbers. But mostly the costs help to establish the importance Tabor placed on gaining this first-hand experience and building a showcase he could use with future customers.”
John Tabor also responded to Carl Seville by posting “If remodeling contractors are going [to] promote and practice green remodeling, we need to be able to approach this with eyes wide open and have a clear understanding of what it really costs to make these improvements. I believe the intent of the article was to share this information with other remodelers.”
Unfortunately, because Tabor only recently completed the project, he does not yet have enough post-project utility bills to provide long-term performance information. REMODELING magazine appreciates Seville’s critique of the article and is encouraged by the comments it generated because they represent a healthy dialogue and discussion about green remodeling. Please add your thoughts on this article in the comment section below.