Project Completion Year
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United States of America
This home, on track for LEED Platinum certification, is all-electric, set for aging in-place, has a minimal environmental footprint, and is located in a great walkable community. It is situated on the owner's original double lot. The two existing 1950's era homes were carefully deconstructed for material recycling. Reclaimed materials from many local sources were used which included vintage scalloped wall paneling, a vintage cast iron tub and laundry sink. Nearly all of the new construction material was USA made.
While larger than the neighboring homes, its massing is split into two primary elements that relate to the neighborhood's scale and rhythm. These two masses are joined by a butterfly roof formed from a series of curved glulams, which dramatically define the main interior space.
Aging in-place strategies were incorporated such as single-floor living, flush floors, a lap pool for fitness, blocking for future grab bars, and wide clearances at doors and hallways. A guest suite doubles as a future care givers space.
For resiliency, a battery back up system, powered by a 7.2kW solar array set atop of the butterfly roof, is pre-wired to supply critical loads during outages. The entire roof has 'Ice and Water Shield' in case of high wind roof damage. Oversized gutters and downspouts handle potential extreme storms.
The landscaping utilizes native plantings and is designed to retain 100% of the stormwater on site via rain gardens, bioswales, permeable pavers and Cultec Rechargers. A 2’ perimeter river rock band serves as a pest management strip.
Sustainable Design Intent and Innovation
There were several overall sustainable and innovation concepts for project. Chief amongst them was that the home's design was to detach from fossil fuels to to the greatest extent possible. To that end, the home is designed as an all electric system without a natural gas line.
Aging in Place was a key design requirement of the owner. This entailed having one level living with zero thresholds, handicap adaptable bathrooms, wide doorways and hallways, blocking for future grab bars, and a caregivers suite. There is also a resistance pool for her fitness routine.
The shape of the building was set as a butterfly roof spanning between two arched roof segments. The butterfly roof allowed for solar panel placement and the dramatic high ceiling provided for a pair of clerestory window groups with remote operated casement windows. Combined with a very large ceiling fan, these windows provide excellent natural ventilation and natural daylighting.
The existing two homes that were on the property were carefully deconstructed by a local deconstruction company.
A high efficiency perimeter shell consisting of continuous insulation, a rain screen system, and a highly efficient windows specified by their orientation.
Nearly all of the building components were manufactured in the USA.
A very high degree of storm water management was implemented in the landscape design.
The project is also solidly on track for LEED Platinum certification.
As noted above, the overall concept for the home's design was to detach from fossil fuels to to the greatest extent possible. To that end, the home is designed as an all electric system without a natural gas line.
The first area of energy reduction was to reduce the size of the house. At 3200 square feet on one floor, it is substantially less than what could be put on the double lot.
Following that, natural daylighting and natural ventilation were designed into the building as part of the main space - operable clerestory skylights combined with a large fan encourage natural ventilation, as well as provided natural daylighting that bounces off of the underside of the butterfly roof around sunrise and sunset.
The perimeter rain screen wall system consists of 2x6 framing filled with cellulose insulation, with a 2" rigid expanded polystyrene (which significantly reduces the global warming potential compared to extruded polystyrene) continuous layer over the entire building shell. Soy based closed cell insulation is used at the cathedral ceilings. A continuous layer of 2" expanded polystyrene is also used under the crawl space slab.
Only casement and awning windows were used as they seal very tightly compared to double hung and slider windows. All windows are made from protruded fiberglass and are low E, double glazed units with argon between the panes. The west facing windows specified with a lower Solar Heat Gain Factor and a lower Solar Transmittance to help reduce the solar heat gain from that orientation.
A series of five zoned air source heat pump electric HVAC systems, controlled by phone based apps, are used throughout and rated to be operational down to at least -20ºF. In lieu of a gas cooktop, an induction cooktop is used. The dryer and water heater are hybrid electric systems that work via advanced heat pump technology. An energy efficient integrated ERV system ensures a high quality of indoor air quality.
All lighting, both inside and out, uses color correct LED bulbs. Monopoint track heads were used at the cathedral ceiling to prevent penetrating through the insulation layer.
A 7.2kW solar PV array is set atop of the butterfly roof, with clerestory windows for natural daylighting and ventilation. Additional electricity required for the house is supplied by an ongoing 100% renewable energy contract, facilitated by the City of Evanston's aggregated renewable energy policy for all residences within Evanston.
This array of high-performance strategies attained a 70% predicted EUI reduction from baseline, from a 49.5 kBtu/sf/yr level down to 15 kBtu/sf/yr, making it one of only 331 national projects in the AIA's 2017 2030 Commitment submittals that achieved the Commitment's current 70% reduction target. Without the onsite renewables, the predicted EUI is 23 kBtu/sf/yr.
The owner moved into the property in May, 2018, so performance records are not yet available.
This home is located very close to local Evanston and Chicago bus routes, and the Skokie Swift portion of the 'El' abuts the rear property line. The 'El' terminal is one mile away, and the bus routes are 0.2 miles away. There are number of restaurants and stores in the area, which gives the site a walk score of 65 and a transit score of 54.
This home was specifically designed for a single woman and has a two car garage, so there are two spaces per occupant. However, there are four bedrooms, so a family of four or more would likely be in there in the future, thereby having two spaces for four or more people.
The garage is prewired for two electric car chargers. The owner currently drives the very efficient Prius C car.
The strategy was to manage 100% of the rain water in a 2" rain event to be able to infiltrate that amount of water on the property and to keep it from entering the larger storm water system.
The way this was accomplished was by building a rain swale that took care of the 487 square foot impervious concrete driveway surface. Additionally, pervious pavement was used for the front entrance and back patio which were equivalent to 366 square feet of pervious paving for the entry area and 507 square feet pervious paving at the rear patio.
Furthermore, there are rain gardens to manage roof runoff from five allocated roof areas. The sixth roof runoff area goes into a smaller area of the property and is sequestered utilizing Cultec Rechargers to manage the 964 gallons of water underground.
There is one 60 gallon rain barrel that was installed to help water annuals located in the backyard.
There are only 287 square feet of drought tolerant turf grass which is only 4% of the landscaped area. 95% of the plants that were selected are drought resistant.
The percent precipitation managed on site is 150% of a 2" storm event from the roof runoff and impervious surfaces. The percent waste water reused on site is 0%. The irrigation system utilizes drip irrigation techniques to minimize water usage. The percent annual regulated potable water use in the designed landscape water requirement is a 93% reduction in water use from the baseline calculated by the EPA WaterSense® New Homes Specification - Water Budget Tool. The annual regulated potable water use is 19.1 gallons per s.f./year. The irrigation numbers are based on the first year establishments needs of the plants, and will go down in subsequent years.
Dual flush toilets and WaterSense® fixtures were used throughout. There is a smaller resistance pool that uses a non-chlorine mixture to clean the pool.
The two existing homes that were on site were carefully deconstructed by the Evanston Rebuilding Warehouse (ERW). Training was provided during the deconstruction process by ERW for disadvantaged members of the community. Several materials from the existing 1950's home were incorporated into the new home. Among these were a 1950's bathtub, scalloped knotty pine paneling, a laundry sink and the kitchen faucet.
As part of the LEED process, there was a serious emphasis that nearly every piece of construction material was made in the US.
The siding is comprised of two environmentally conscious siding materials. The upper siding is cement fiberboard, made with waste wood. The main siding on the house is from Boral is made from fly ash, which is the primary byproduct of burning coal.
Exposed structural glulam beams support the butterfly roof. The glulam beams are more resource efficient relative to solid framing as they are comprised of smaller structural elements glued together.
In keeping with the fossil fuel free concept, there is an 'electronic fireplace', which features a dancing flame image projected onto a screen set back from a mesh screen. A heat option allows for electric heat when desired.
The kitchen countertop and the backsplash tiles were made from reclaimed materials. Several light fixtures were also repurposed. Low and no VOC sealants, adhesives and paints were used throughout.
Design Architect (FIRM)
Kipnis Architecture + Planning