"The funny thing is that it is all working beyond our expectations," McDonald said, referring especially to the new solar-powered electrical system.
"After living here for a couple of months, we realize that we already have a surplus that goes back into the grid." If that pattern continues, they may never have to pay for electricity.
"When we built in solar features, we thought they would reduce just half our electricity bill," McDonald said. That's because the number of solar panels was limited by cost and the roof space available. Perhaps the panels perform better than he expected because McDonald put dimmers on all the lights, and installed high-efficiency appliances and passive and active solar features that add up to more energy savings.
The Margarido House was built on a steep lot that had passed, through several hands, from a family that preferred to move rather than rebuild after the fire. Its many fire-resistant materials include concrete and tile on the exterior, permeable sidewalks and surrounding landscaping, and cement floors inside. But what makes it remarkable is its potential ranking - despite being too large to be a true poster child for the green movement - as the first Northern Californian LEED-H Platinum custom home.
"The house is so large, we started out with negative points for our LEED certification," McDonald said.
But, just as the solar panels performed better than expected, McDonald found that other green design features of the home - his first ground-up structure - surpassed the green goals the couple set out to achieve.
The L-shaped split-level house is a collaborative design by several architects and designers. Bay Area architects David Wilson and Chris Parlette sited it; details were completed in Philadelphia by one of McDonald's brothers, architect Tim McDonald; McDonald Construction & Development in Oakland built it; and Ian Reed of Medium Plenty interpreted the detailing and managed the interior and exterior designs.
"We did not even think we could achieve a Platinum rating at first," McDonald said. But in June 2006, after they had already opted for a green roof, a cistern for rainwater, passive solar heat gained through floor-to-ceiling glass walls and additional solar power collectors on the roof, a friend, green consultant Steve Barnes, told the couple about a new pilot program for residential LEED accreditation.
They soon documented all possible ways they could improve their accreditation. McDonald eliminated any need for air conditioning by using operable windows that allow cross-ventilation, and added 25 percent fly ash to all the concrete poured for the slab-on-grade foundation, walkways and retaining walls. They aimed for Silver LEED certification and hoped to do even better.
Homeowners who sign up for accreditation pay $5,000 and get an architect or a qualified inspector to manage the LEED-points process. "You also get access to a lot of resources and like-minded people," McDonald said.
One key discovery he made was that many of the systems that home developers install are not needed in the Bay Area. Reinterpreting codes to save time, money and materials are a valid way to be green.
He carved the square footage they needed for the house from the hill and rearranged the excavated soil to extend the building pad. This arrangement also eliminated costly and environmentally unfriendly cement piers and achieved additional passive geothermal heating and cooling for the hunkered-down home.
"We got more points to qualify for a higher rating simply by not using traditional heating and cooling systems," he said.
McDonald's passive geothermal system and in-floor radiant heating are both energy savers.
"We really wanted a prototype of what was possible. We wanted high design and high sustainability in a large home," McDonald said.
"We got more points to qualify for a higher rating simply by not using traditional heating and cooling systems," he said.
McDonald's passive geothermal system and in-floor radiant heating are both energy savers.
"We really wanted a prototype of what was possible. We wanted high design and high sustainability in a large home," McDonald said.
Unlike previous owners who were daunted by the steepness of the site, McDonald got permission from Oakland's building department to rearrange the lot so they could build low, meet new safety standards and codes, and keep views from being obstructed.
Teamwork
With a "green can be beautiful and sexy" mantra, he was able to attract artsy local businesses interested in the same thing, especially Mark Rogero, owner of Concreteworks in Oakland, and Cathy Bailey, proprietor of Heath Ceramics in Sausalito. They provided new ideas for beautiful fire-resistant siding made of recycled kiln shelves, and locally produced tiles and counters for the kitchen and bathrooms. Rogero and Bailey became part of a collaborative team that included others from Oakland - Lauren Schneider of Wonderland Gardens, who planted Margarido House's living roof, and metalsmith Chris French, whose hand-bolted aluminum and steel fire-resistant staircase leads from the front garden to the roof garden.
McDonald's choice of a local team made the collaboration and any last-minute alterations to the design practical, plus it conserved gas and reduced transportation costs. With each success, they inched their way toward LEED-H Platinum qualification. To inspire others to do the same, he set up a Web site where people could follow their progress; it has become a virtual green show house and a resource guide.
"You can even locate the person who laid the tile," McDonald said.
He attributes his success in pulling off the venture for about $250 a square foot less than normal, about $900 a square foot, to contributions and concessions from Rogero, Bailey and other suppliers. Another factor was his considerable business expertise; he's started several sporting and outdoor goods companies. More recently, he has been converting dilapidated East Bay Victorians into modern homes.
Infill points
Margarido House is not only McDonald's biggest project, it is new because the site it is on was destroyed by fire. However, most of the old homes on his street are still intact. An in-fill house in such an area, which has stores you can walk to, is awarded extra points according to LEED guidelines, McDonald says.
The size of Margarido House is in keeping with the neighborhood.
"Most of the houses that are around us are big homes on half lots," McDonald said. He could have built a smaller, 2,500-square-foot home, but given the demand for bigger homes on expensive $875,000 lots such as theirs, McDonald and his wife chose to stay in step with the market.
Still, unlike most of the 5,000 new homes that replaced only about 3,000 lost in the 1991 fire, McDonald and Martenson's five-bedroom, five-bath home with an in-law suite does not seem overwhelmingly large.
To reduce his home's environmental impact, McDonald has used zero-VOC paints, recycled materials and a blown-in soy-based insulation in the walls. "Even much larger, 12,000-square-foot homes are often considered sustainable just because they are built with straw bales and rammed earth," McDonald said.
Size notwithstanding, come September when Margarido House will be ready for inspection, its innovative features and energy-use ideas will surely get the platinum award. "We have 118 points already," McDonald said. "All we need is 102 points to qualify."
Reaching Platinum
We were able to climb all the way back to Platinum because of two things:
-- The extensive amount of "ratable" green elements that we incorporated into the project.
-- A series of creative design elements and solutions we incorporated were awarded extra credit points. These "Innovation and Design" credits are awarded extra points outside the normal rating system.
Some of the more important elements are:
Exterior
-- More than the required amounts of permeable area; 90 percent of the lot (not including the building footprint) is permeable, including most of the driveway via a "permeable paving system."
-- Comprehensive rainwater and groundwater catchment system; 4,000-gallon underground cistern captures rain, roof and groundwater for irrigation needs.
-- Minimum 25 percent fly ash content in all concrete site and retaining walls.
-- 600-square-foot "living" or "green" roof and deck.
-- Energy Star cool roof
-- Solar PV system; Solar Thermal (hot water) system
-- "Thermally broken" dual pane, low E, Solarban 60 windows and doors
-- Innovative LED lighting for all exterior and landscape lighting; 260 percent better than Energy Star lighting requirements
-- Passive solar design that incorporates a unique aluminum and steel shade canopy, large upper-story "eyebrow" shading and floor-to-ceiling windows oriented south and west.
-- Operable windows and doors designed to take advantage of prevailing winds coming off the bay; no mechanical cooling required.
-- Use of recycled kiln trays from Heath Ceramics as exterior wall tile and pavers.
-- Rain screen wall system (creates an air cavity between siding and waterproofing material).
Interior
-- Solar-assist, on-demand, in-floor radiant heating system.
-- Zero-VOC paints and finishes.
-- Computer-controlled indoor air-quality management system, lighting and power window shading system.
-- Push-button hot water D'mand system at each water fixture (no wasting water while waiting for it to get hot).
-- House bunkered into hillside for geothermal cooling and heating effect.
-- Innovative framing techniques that minimized lumber waste and maximized use of recycled materials.
-- Recycled glass and concrete counters.
-- High-efficiency appliances, lighting, shower heads and toilets.
-- Spray-in, soy-based foam insulation that produces higher R values in same thickness and is free of VOCs.
-- In-wall vacuum system (no dust or allergens blowing around from a conventional bag vacuum).
-- Passive solar: Large interior installation of thermal-mass materials, such as tile and concrete flooring and walls. Concrete and tile absorb heat during the day and radiate back at night.
General
-- Maximum use of locally sourced and manufactured materials.
-- Comprehensive recycling and waste management plan during construction, resulting in 80 percent of off-hauled waste recycled.
- Mike McDonald
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