This new, partial two-story modern residence with guest house and pool has been constructed on a vacant lot with oaks and open meadow. The home was sited on the lot to minimize tree impacts and take advantage of the oaks for afternoon shading to reduce the thermal load of summer. The design cut the house into the site so that the roof forms flow into the slopes on the south side of the property; this includes the use of a green, living roof over the garage. Minimal planting was proposed and landscaping is directed at oak and grassland preservation as well as maintaining the natural, open beauty of the property.
Newly Constructed Residence
Green Design Elements
Home Automation System (with weather station on roof to control energy efficiency) The custom home automation system was developed by the home owner and is expected to be released as open source. It integrates numerous systems throughout the house, including lighting, security, thermostats, window shades, pool, irrigation, weather station and media. Additionally, the photovoltaic inverter output, electrical usage, irrigation water consumption and temperatures at approximately 20 locations around the house are monitored continuously and recorded.
Conservation also is central to the design of the home automation system. Energy saving features include the ability to easily turn off any lights, thermostat, pool, spa, TV or media device; to minimize pool pump solar heating running time; to minimize running time of hot water recirculation; to control window shades based on thermal load; and to make real-time power and water usage visible. Water saving features include adaptive irrigation timing based on weather and rainfall, and an irrigation flow meter to detect failed valves.
Green Roof on Garage Green roofs reduce heat gain into and cold loss out of the building, help protect roof waterproofing layers, prevent stormwater runoff, and increase building aesthetics. The layers of this green roof include, starting from the top: plantings in light-weight soil, a root barrier and drainage mat, 4" - 6" of reinforced concrete, a steel deck, and I-beam spans supported by 12" thick walls of concrete.
Constructing this garage:
Construction of 12" thick walls and roof- Supporting steel I-beams
Steel roof decking to support the con- Pouring the 4" - 6" concrete layer.
crete roof layer.
Spreading hot rubber for waterproofing. A fabric layer provides reinforcement of
the waterproofing layer.
After a second layer of rubber is spread, Sheets of MiraDrain™ drainage composite
a root barrier sheet is placed. are placed over the root barrier.
Foam board insulation is then placed Drainage piping is laid at the insulation
over the MiraDrain™ layer. layer...
...and drainage matting is then set in
On top of the drain mat, a layer of filter fabric is installed to prevent soil from clogging the drainage. At this point, the roof is now ready for light-weight soil, drip irrigation, and planting. The planting for this green roof was designed to look like a river flowing down the roof.
Metal (steel) Roof Metal roofing is durable, does not warp, split or crack and is impervious to mildew, rot, termites, and pests. If properly cared for, metal roofing will last a very long time. The color chosen for this roof qualifies as cool roof compliant.
Electrical Outlet for Future Car Knowing electric cars will be part of their future, a 240V electrical car outlet was installed in the home's garage at a location with easy access for charging.
Passive Design The home has numerous floor-to-ceiling windows that allow for plenty of natural lighting, even in winter. Operable windows have been positioned to maximize cross-ventilation in each of the rooms. The kitchen, breakfast nook, family room, and parents' office are on the north side of the house, allowing the primary living spaces to stay relatively cool during the warmer months.
Solar PV systems consist of a series of panels (modules) which produce a DC current. The panels are connected to an inverter which converts the current to AC for use in the home. This home has about a 10 kilowatt system. The location of this home's PV system is on a south-facing roof, resulting in an optimal orientation. Flat roofs also work well for PVs as frames can be tilted toward the south to maximize solar energy gathering. While batteries are often included to provide backup during power outages, this home employs a backup generator.
Solar Hot Water for Pool The flat black panels are made up of many small tubes that capture the sun's warmth and transfer it to the circulating pool water.
Solar Hot Water for Domestic Flat plate solar collectors contain an anti-freezing heat-transfer liquid which collects the sun's warmth and heats the domestic water through a heat exchanger in the storage tank.
Ventilation System The home has two ventilators with built-in heat exchangers which bring in and warm outside air. The warmed fresh air is then distributed through the house via the forced-air system for improved indoor air quality, even in the winter.
Copper Piping While copper is a limited natural resource, it also is highly durable and long lasting, is easy to install, requires less maintenance/repairs, and is recyclable.
Radiant Hydronic System This home as 13 independent zones to service the different heating needs of various rooms in the house. Hot water circulates in tubing set in the gypsum concrete floor to more efficiently heat rooms than using forced air.
Low-VOC Paint Volatile Organic Compounds are a wide variety of potentially harmful gases. The drying of conventional paints, stains, and adhesives all produce VOCs. Low-VOC paints were chosen for this home to help improve the indoor air quality. No-VOC paints can be even more effective.
Wool Carpets A typical synthetic carpet contains about 120 VOCs, some of which are neurotoxins, and will off-gas for at least 3 to 5 years. One of the most commonly installed types of natural, renewable carpeting is wool, as was installed in this home. Wool is a highly durable, longer-lasting healthy substitute for synthetic carpeting.
Q & A: The Owner's Feedback
Did you have these numerous green design elements in mind for your project when you first sought an architect? Or did your architect assist you by providing sustainable options/information as the design took shape?
"We had some of the elements in mind. In particular, we were interested in solar heating, a metal roof, outside-air ventilators, and a smart home automation system. Our architect suggested the green roof, and our designer suggested the low-VOC paints."
What particular sustainable design elements were you certain you wanted and would not compromise by eliminating them from your project?
"We had an open mind and evaluated each of the sustainable elements on standard of living, aesthetics, and cost-effectiveness. We were able to keep most of the elements we researched in our project."
Have the costs for your project's green elements been higher than expected? If so, did you eliminate any due to budget constraints? If so, which, and what did you opt for instead?
"The only system that ended up more costly than we expected was the solar system for our domestic hot water."
"There were two systems we looked at, but didn't include because they didn't appear to be cost-effective: (1) geothermal heating and (2) water run-off storage and reuse. We designed our drainage system so that we could easily add a water storage system in the future."
Did you have any difficulty obtaining the various sustainable products used in your project? If so, which and why?
"Because we wanted to complete our project quickly, we didn't include any sustainable products that would have held up our project."
Do you have any further comments about your choice of sustainable design elements, the construction process concerning these design elements or...?
"We have been able to monitor our use of resources through our home automation system. In the future, we hope to integrate more automatic control of our house subsystems (e.g., window coverings, irrigation, etc.) using real-time data from our weather station."