|Exterior work done on the existing home included replacing the siding, roofing, garage doors, entry door and some windows.|
Price remains a big factor with many remodeling clients and therefore with remodelers. Added cost is probably the most cited reason why contractors haven't flocked to green remodeling. But the price equation is being reframed.
Model reMODEL 2002 proves that energy-efficient techniques and materials can save a homeowner more than $700 per year in utility bills. Combine that kind of data with growing public concern over mold and indoor air quality, and green or sustainable remodeling gains a lot of appeal. And the EarthCraft House approach used in Model reMODEL helps homeowners and remodelers decide which techniques and materials will provide the most bang for the buck.
"We do not want this to be cost-prohibitive," says Jim Hackler, project director of EarthCraft House, a partnership between the Southface Energy Institute and the Greater Atlanta Home Builders Association. "The second it becomes cost-prohibitive, no one's going to do it, and then theres no impact on the environment." EarthCraft has certified new homes since 1999, but Model reMODEL 2002 is among the first pilot projects in EarthCraft's new renovation program.
Homeowner Joseph L. Scibilia bought his three-bedroom, two-bath, two-story home in Atlanta in 1997. Last year, he and wife Kie Sian approached SawHorse Inc., an Atlanta design/build remodeling firm, about expanding their family living space (they have a toddler) and updating the kitchen, bathrooms and furnace. The design process began last December, and they signed a construction contract in March for remodeling a first-floor bathroom, updating the HVAC, refinishing the wood floors, painting inside and out, plus a two-story addition including a master bathroom expansion, kitchen, family room and deck.
|Insulating the attic to the roof line brought the HVAC system within conditioned space.|
"Many of the things we were doing lent themselves to doing EarthCraft at the same time. It was a good fit," Scibilia says. "At first I was reluctant to go with it because I did not fully understand what it meant and I was trying to keep costs to a minimum. Once I realized the increased energy efficiency and air quality and projected cost savings, I was sold on it."
Setting the standards for green remodeling
National green-building programs such as Building America and Energy Star and regional programs such as EarthCraft have gained recognition among new-home builders and created demand among homeowners.
Remodeling, as always, presents more of a challenge. Just as every remodeling project has a big impact on many aspects of a client's life, each project has an impact on many aspects of the house. Even smaller or more contained renovations such as new roofing, a first-floor addition, a bath redo or replacement windows affect how the house performs, from heating to cooling to air and water infiltration.
Some of the significant energy-efficient techniques require making changes throughout the house, not just in the portion being remodeled. It can be difficult to know which changes will have the most impact on the home and the least impact on the budget. Besides, as most building codes recognize, it can be extremely costly and unrealistic to bring existing houses up to new-home standards.
Last year, at the urging of local contractors - led by SawHorse vice president Carl Seville - EarthCraft began developing a renovation program to give remodelers guidelines and goals. The training costs $50 per person for the class, plus $150 to join EarthCraft. Eight pilot projects now are completed or near completion. Hackler plans to launch the program formally this fall and eventually roll it out nationally.
The core of EarthCraft is energy efficiency - in appliances, lighting, insulation, windows, HVAC installation, and building techniques and materials. But the program also emphasizes resource-efficient design and building materials, waste management, indoor air quality (including moisture control and ventilation), and indoor and outdoor water management.
|Foam insulation provided a tight air seal for the walls and ceilings.|
An EarthCraft remodeling project begins with a certified Home Energy Rating System rater conducting a duct pressurization test to measure leakage and a blower door test to measure air infiltration throughout the house. (To find a rater in your area, contact the Residential Energy Services Network at www.natresnet.org.) Based on these figures and on observations about the home (type of window and furnace, for example), the rater uses a software program called REMrate to provide a HERS score.
The initial findings are accompanied by a report offering a range of options for improving the home's performance, with potential savings individually modeled for each improvement. The report also includes REMrate estimates of current heating, cooling and water costs; those costs if the remodeling is done to meet minimum energy code requirements; and potential costs based on the EarthCraft improvements most likely to be made.
The homeowner and remodeler - who must have completed a one-day EarthCraft training program - choose what to implement. At the end of the project, an EarthCraft rater visits the home for a final inspection, including another blower door test and duct test. The entire inspection process costs $400 per house. To qualify as an EarthCraft house, the home must achieve a minimum total point score.
|A foam sealant, applied by assistant project manager Steve Yulo of SawHorse, took care of the windows and doors.|
"EarthCraft isn't prescriptive," Seville says. "You just have to do the right things in the right combination."
EarthCraft new homes need at least 150 points, with 75-85 of those coming from energy-efficient measures. Remodel requirements vary depending on the scope of work. Projects that do not add conditioned space to the home need 120 points. Those that add conditioned space but keep it within the existing structure need 135. A room addition without a foundation requires 150 points; that rises to 165 for an addition with a foundation. From 60 to 100 of those points must be generated from energy-efficient measures.
In addition, the HERS score must improve a certain number of points (the exact number is yet to be determined). New homes must achieve a score of 80 per the 1993 Model Energy Code; 86 qualifies a home for Energy Star status. "When they're done," says Mark Newey, EarthCraft's technical coordinator, "most of these EarthCraft projects are coming out better than new homes."
|The new HVAC system in the basement replaces a 25-year-old furnace and metal ducting.|
Turning theory into practice
In April, before construction began, the Model reMODEL home received a HERS score of 66.4. Newey, author of the EarthCraft report on the Scibilia house, says Atlanta-area homes built more than 15 years ago tend to score from 60 to 70, while homes built five to 15 years ago usually score from 70 to 80.
Newey presented SawHorse with a list of 21 potential improvements (see table). Replacing existing windows with double-pane, wood-frame, low-e windows would reduce heat loss, heat gain and air leakage. The furnace, which was at least 25 years old, needed to be replaced with a more efficient unit, and the new addition also required an efficient furnace. Ditto for the air conditioners. Newey suggested a range of insulation options for the basement, pre-existing exterior walls and the attic. He also recommended removing part of the existing ductwork, replacing other parts and then using mastic to seal all joints and seams.
|Light-colored roofing materials that reflect the sun earn EarthCraft points for durability, as do roofing materials with a minimum warranty of 25 years.|
Depending on which changes were made, Newey estimated that the house's heating and cooling requirements could be reduced from 150,000 Btu per hour of heating capacity and 6 tons of cooling capacity to 110,000 Btuh and 4.5 tons. He later did Manual J calculations to determine the heating and cooling load and Manual D calculations to determine duct sizing, passing that information along to the HVAC subcontractor.
Proper sizing of the heating and cooling systems is one of the top three improvements a remodeler can make, Hackler says. "Believe what Manual J says," he advises. "It already has a fudge factor. HVAC contractors often push it up, and they don't need to."
Sealing the ductwork with mastic is also in his top three, along with air-sealing the entire house, particularly around outlets, recessed cans, tubs, windows and doors.
Seville agrees. "An oversize air conditioner will cycle so fast that there's no time for it to pull moisture out of the air, which leads to moisture and comfort problems."
|The addition rests on piers rather than a foundation because of an Atlanta code requiring a 75-foot setback from streams.|
As it was, the Scibilias' air conditioner, located in the uninsulated attic, had to fight summer temperatures that rose to 140 degrees. That was one of the main reasons SawHorse insulated the roof line of the main and side attics with Icynene, a spray-in foam insulation. In addition to bringing the ductwork within the insulated shell, it also eliminated the need to air-seal the walls and ceiling bordering the attics. It also allowed SawHorse to use recessed lights without worrying about heat loss through the roof.
Project manager David Shepherd estimates that it takes 25-30% more time to use the foam insulation instead of batts and costs about 50% more for the product, but he says the results are worth it. "Being in a house in the middle of summer with no air-conditioning on and having it be 20 degrees cooler inside than outside is pretty impressive."
Shepherd had his crew use the foam insulation in all walls of the new addition and also employ advanced framing techniques that make more room for insulation. Shepherd and Seville do offer a warning about using it in existing walls: Foam insulation expands a great deal in a short time. On an earlier project, the foam oozed out.
|The U-shaped kitchen - part of the new addition on the back of the home - includes wood cabinetry, solid-surface countertops and low-e windows. The advanced framing techniques illustrated at right ensure that the walls contain more insulation.|
In the interest of being resource-efficient, SawHorse turned to wood alternatives throughout the project. Although more expensive than wood, engineered lumber - in this case, Trus Joist's TimberStrand headers, studs and plywood sheathing - can take more of a load. That means headers are smaller and more insulation can fit in the wall.
"We sacrificed a little R-value by using plywood sheathing, but the Icynene does such a great air-sealing job that it provides a great envelope overall," Seville says. "We could have used 2x10s with insulation between them for the headers, but the opportunity to use the manufactured lumber showed the use of a more renewable resource than solid lumber."
For the same reasons, much of the trim was made from finger-jointed lumber. And when it turned out that the siding had asbestos and had to be replaced, SawHorse recommended James Hardie's Hardiplank as more durable than wood siding.
Other measures that earned EarthCraft points include using low-VOC paints inside and out, replacing the old furnace and air conditioner with new units, and replacing all the ductwork in the home, a decision made after the HVAC contractor suggested it could be done within budget.
Though donations from Model reMODEL sponsors make it difficult to determine exactly how much more remodeling for EarthCraft certification cost on this project, Seville estimates it was no more than 5% of cost. Building a new home to EarthCraft standards costs builders approximately 0.5% to 3% more than standard, EarthCraft says.
"EarthCraft standards give significantly higher value, and as long as we plan it upfront, the cost difference isn't that much," Seville says. He acknowledges that not all clients will want to spend more money on initial costs to realize long-term savings, but he is incorporating a number of EarthCraft building techniques into SawHorse's standard practices to ensure quality construction.
In the end, the Model reMODEL home's HERS value increased by 19.6 points to 86.0, 30% more efficient than code. Projected annual savings are $538 in heating bills and $175 in cooling.
For the complete HERS report, more photos and useful links, visit www.HousingZone.com/projects/modremod02.