Green Renovation: Same Footprint, Twice the Space

Decatur, GA

May 9 2009 By Jesa Damora | 2 comments

General Specs and Team

Location: Decatur, GA
Cost (USD/sq. ft.): $126/sqf

Living space (addition): 1,620 sq. ft.
Existing space (remodel): 1,345 sq. ft. (built in 1939)
Completed: April 2006

Builder/contractor: Robert Soens, Pinnacle Custom Builders LLC
Architect: Janis Wayne, AIA
Interior designer: Craig Kettles, C Designs
Energy analysis and Certification: EarthCraft Homes, Southface Energy Institute

Construction

Foundation: plastic vapor barrier encapsulating existing 8-in. CMU walls and concrete slab; band joist sprayed with Icynene foam (R-14)
Existing walls: 2x4 stud framing, batt insulation, brick veneer; all wall penetrations caulked and sealed
New (second-floor) walls: brick veneer, 1-in. air space, #15 felt, OSB, 2x4 studs, Icynene spray foam (R-22)
Windows: double-pane, low-e (Monarch)
Roof: 35-year architectural asphalt shingles, #15 felt, OSB, 2x10 rafters, Icynene spray foam (R-22)

Energy

Heating/cooling: first floor, gas furnace (Lennox); second floor, electric radiant heating in master bath and air-to-air heat pump (Lennox)
Water heating: Tankless water heater (Rinnai)

  • Windows placed for daylighting, natural cooling/ventilation
  • Initial energy evaluation to gauge improvements
  • Spray-foam insulation (Icynene)
  • Programmable thermostats (Honeywell)
  • Energy Star dishwasher (LG), refrigerator (GE)

Water Efficiency

  • Native plants
  • Low-flow toilets and faucets (ADA-compliant Toto and Kohler)
  • Efficient plumbing layout

Indoor Air Quality

  • No carpet
  • Natural ventilation
  • Mechanical ventilation in bathroom (Fantech) and kitchen (Jenn-Air)
  • Encapsulation of basement for moisture control
  • Radon venting
  • Green Materials and Resource Efficiency

    • Careful detailing of drainage for durability
    • All construction debris recycled or repurposed
    • All brick from original house reused in renovation
    • Exterior rain barrels incorporated into revised roof and gutter system

    An Earthcraft-certified second-floor addition makes this Georgia home more livable and energy-efficient

    Originally a small house on a small hill in the heart of Decatur, Georgia, this home grew to meet its owners' needs in an environmentally friendly way with an EarthCraft-certified addition.

    Owners Robin Futch and Jenny Gould have more than doubled its size and redefined its style by deconstructing the top of the house and building almost entirely on top of the existing structure. Their determination to build green paid off: Their home is more energy-efficient and more in tune with its surroundings, and only a minimum of resources was required to make it so.

    Balancing possibilities and dollars
    Renovations are often harder to do than new construction because of the need to adapt to preexisting situations, and green renovations are no exception. Opportunities can be as daunting as problems.

    Robin and Jenny understood that the smorgasbord of possibilities facing them didn’t constitute a plan. They knew they didn't want a ground-source heat pump — nor a garage, although one is planned for the future. The lot limitations pointed toward expanding up.

    They brought a list of well-considered intentions and a general budget to Janis Wayne, a local architect, and came away with a set of plans. A new second floor would provide a master bedroom and bath, a second bedroom and bath, a cedar closet, and an easily accessible laundry room (so they wouldn’t need to squeeze down the narrow basement stairs).

    In the existing space, they would get a completely new kitchen. Other areas would be reworked into a media room, office, and entry; there would also be a large new screened patio. The renovation would also provide several new systems — including a built-in vacuum cleaner, a whole-house sound system, and a new air conditioner.

    Robin and Jenny hired an EarthCraft-certified builder, Robert Soens of Pinnacle Custom Builders, to implement these plans in an environmentally conscious way. Soens helped refine their vision and further focus choices; to improve indoor air quality, for example, he suggested using polyethylene to limit moisture and radon entry into the basement.

    The 6-mil poly was installed over the basement’s dirt floor; it was also attached to the basement walls to limit air infiltration and moisture transmission. Wood strips screwed into the wall hold the plastic in place, and all the edges of the strips are foamed so that even the tiniest screw holes won’t leak air. A vent pipe running up to the roof exhausts any radon from under the floor poly. Pinnacle also spray-foamed the band joists between basement and first floor.

    Setting priorities
    Air sealing and insulation upgrades should be automatic for anyone doing a major renovation, since the work saves significant amounts of energy. Robert often finds himself saying things like, "It makes no sense to buy a big new heating unit if you lose thirty percent of that energy to the outside air." Fortunately, the EarthCraft program provides a thorough strategy checklist.

    Upgrading the old
    The new walls are insulated with Icynene spray foam. Workers diligently foamed the deepest reaches of the eaves to eliminate convective air currents. However, Pinnacle didn’t replace the insulation in the existing walls — 3 1/2-in. fiberglass batts — because the money was better spent elsewhere.

    All the drafty ductwork in the existing structure was replaced with a new, tightly sealed system, and other potential sites of air leakage, such as electrical junction boxes and holes for wiring, were fastidiously sealed.

    The crew replaced the existing windows mostly for aesthetic reasons, with the added benefit of reduced heat loss in the old portions of the house.

    In with the new
    These measures were performed in the new construction as well, of course. Pinnacle put 5 in. of Icynene spray foam between the new rafters, carefully installed a water-resistant barrier over the exterior sheathing, and thoroughly caulked the new windows.

    The house uses forced hot air from a high-efficiency gas furnace on the first floor and an air-source heat pump on the second floor. A tankless Rinnai water heater in the new attic replaced a 40-gallon, standard-efficiency heater in the basement. Even after more than doubling the size of the house, electric bills are lower — in spite of the in-floor electric radiant system that warms the bathroom. Gas bills have increased, though, perhaps because only Robin lived there in 2003, and now two people use the renovated space a lot more.

    Lessons Learned

    Robin and Jenny chose EarthCraft above other green building programs because it was straightforward and more comprehensive than the Energy StarLabeling system sponsored by the Environmental Protection Agency and the US Department of Energy for labeling the most energy-efficient products on the market; applies to a wide range of products, from computers and office equipment to refrigerators and air conditioners. program of the time, which would not have included components like indoor air quality or recycling. The other alternative would have been to hire an independent tester, who would not have provided a full range of options and trade-offs. Certification programs have evolved rapidly, and there is now a wider choice featuring different areas of focus and documentation costs. EarthCraft remains both a premiere program and the one best understood in the Atlanta area. A substantial list of programs, by region, can be found at PATH, a private-public partnership for advanced housing technologies.

    Smart choices make green affordable
    Robert stresses that incorporating sustainability into the construction of a building is really just a question of common sense. Although many people think going green is expensive, Robert’s experience is that unless (for instance) you’re installing photovoltaic(PV) Generation of electricity directly from sunlight. A photovoltaic cell has no moving parts; electrons are energized by sunlight and result in current flow. equipment or a ground-source heat pumpHome heating and cooling system that relies on the mass of the earth as the heat source and heat sink. Temperatures underground are relatively constant. Using a ground-source heat pump, heat from fluid circulated through an underground loop is transferred to and/or from the home through a heat exchanger. The energy performance of ground-source heat pumps is usually better than that of air-source heat pumps; ground-source heat pumps also perform better over a wider range of above-ground temperatures., the cost per square foot should be about the same. He adds that greening a house requires a good bit of study to make sure you’re spending your dollars wisely. In some cases, that means forgoing work — for example, choosing other improvements instead of ripping out and insulating the walls.

    Because the team managed costs well and took advantage of all the EarthCraft offerings, they were able to incorporate many amenities. Originally damp and cold in winter and moldy and humid in summer, this home is now a comfortable place with healthy indoor air quality. Robert reports that green-certified homes in Atlanta are selling in about half the time and at a higher percentage of the asking price than conventional homes. He's now building several other LEEDLeadership in Energy and Environmental Design. LEED for Homes is the residential green building program from the United States Green Building Council (USGBC). While this program is primarily designed for and applicable to new home projects, major gut rehabs can qualify. - and EarthCraft-certified homes there and is a sought-after lecturer on optimizing construction choices for sustainability goals.


    —Jesa Damora is a free-lance writer in Somerville, Mass.

    Tags: , , , , ,

    Image Credits:

    1. Robert Soens

    1.
    Wed, 05/20/2009 - 14:08

    just don't like the night lights
    by Tom Good VGBN.org

    could read the whole article, but i just didn't like the main photo of artificial illumination being used for whatever you call that. Was it permanent (the lights). Didn't see and remote generation, so assume the kw used to light the building at night is from grid. Perhaps it is a bird strike deterent? Sorry to nit-pick - its just that the picture was worth the many words.


    2.
    Wed, 05/20/2009 - 19:21

    Exterior lighting temporary.
    by Robert Soens

    The lighting used for the exterior was temporarily placed just for the photography. No permanent exterior lighting has been installed other than for security purposes.


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