Ellman-Raiselis Passive House Residence in Tarrytown
Several years ago, when her sons went off to college, Tarrytown Planning Board member, architect, and passionate environmentalist, Joan Raiselis, decided that reducing the family’s environmental footprint was her paramount ambition. She and her husband, Fred Ellman, a designer, owned an old six-bedroom house on Fairview Avenue but felt like they were two people in a house meant for four or six or more with the accompanying energy demands. Minimizing their own resources demand was a big goal. So, they removed the garden in their adjacent lot in order “to create a space where we could live in as sustainable a way as possible,” she said. Her next questions were: “What does that mean? And, how far can we go?” To “net zero,” as it turns out.
She attended Al Gore’s Climate Reality Project’s three-day session in Chicago which provides training to learn about and disseminate information on climate change, and she returned more confirmed than ever that they would use no fossil fuels at all in their new project. In creating the most efficient house possible, they made a multitude of choices that would ensure using all resources efficiently to create as little waste as possible.
Designed collaboratively with Til Globig, a friend from architecture school, who works at di Domenico + Partners in Long Island City, Globig had the skills to do the design for the “house machine,” and as a team, they chose the materials and aesthetic design. At a gross 1,900 square feet, with about 1,500 square feet of living space, the house is modest, but with views to the Hudson River; with a double-height living/dining room area on the first floor, the design makes it feel spacious. Their ground floor consists of a master bedroom and bath, plus a kitchen/dining/living area, which is their home core. Their second floor includes a study, second bathroom and a bedroom for overnight guests. But, “there are places for eight people to sleep with couches chosen for sleep-ability and a Murphy bed in my office,” Raiselis explained.
Passive House Strategies
The “passive house movement” began in Germany and is a rigorous, voluntary standard for energy efficiency in a building, which reduces its ecological footprint. The resulting efficient buildings require little energy for space heating or cooling – about 10% of the energy required for a similarly sized house. Here are some of the many energy-saving choices Raiselis and Ellman made to achieve their net-zero status (The term “net zero” refers to a standard in which the total amount of energy used by their home on an annual basis is roughly equal to the amount of renewable energy created on site):
- Twice as much insulation as a house compliant with state and federal building codes.
- Triple-glazed European-made windows with the highest possible efficiency (their only non-domestic choice since the efficiency rating they wanted was not available in the United States)
- South-facing windows to take advantage of the sun’s warmth in winter months, perfect for solar gain as well
- Twenty solar roof panels, calculated for how much energy the couple expects to use and what the state allows
- All seams, nail holes and joints are taped close – around windows and doors, between insulation panels, at holes in the fiber sheeting holding in cellulose insulation, etc. – maximizing air-tight construction, minimizing drafts and heat loss
- No basement – with house slab insulated underneath as well as around the shell.
- Energy Recovery ventilator (ERV) installed in attic so fresh air comes in, is brought to room temperature within the ventilator and is circulated constantly throughout the house.
In winter months, on cloudy days, and at night, the house may pull energy from the grid, but electricity generated during sunny days and in summer offsets any electrical usage. “In February our ConEd bill was $142, but from May through October, we estimate we will be producing more than we use.” Raiselis explained. In fact, they give back to the grid often through net-metering, a solar incentive that allows them to sell energy back to the electric grid. When their solar panels produce excess power, that energy is sent to the grid, and in exchange they can pull from the grid when their system is under-producing.
Material Choices and Appliances
Raiselis researched material choices and sourced as locally as possible. Synchronicity emerged during her search. At the Tarrytown Farmers Market, the owner of Misshapened Bowl, a woodcarver from Kitchawan, mentioned he had plenty of milled white pine from a tree he felled in his yard. Seven-eighths of the house now displays this find. “All the floors, except for one bedroom– inclusive of knots, stains and burls; it’s from a tree and it has its own story,” explained Raiselis. Their son, Aydan and a family friend, Gily Moshe, laid the floor in the second bedroom.
Any wood staining was done with a 0% VOC stain (volatile organic compounds – organic, carbon-based chemicals that evaporate at room temperature.) made from flaxseed. All paint is 0% VOC, as well. Another son, Lloyd, made the bathroom vanity. Raiselis cleans everything with vinegar and water.
Appliances were chosen for energy efficiency after consulting Consumer Reports. Downsizing to a smaller refrigerator helps conserve energy, as does an on-demand water heater. With no hot water tank, they are not heating water and letting it sit.
Air-conditioning can be utilized at no cost. As Raiselis noted, “This is the most comfortable house I have ever lived in! We never had AC in our old house.”
When the warm weather arrives, the Ellman/Raiselis family shifts much of its lifestyle outdoors to the substantial deck, Ellman’s meditation garden, or Raiselis’ organic garden integrated around it. There is no grass to cut, and leaves are chopped for use as compost. Extra yard trees were planted to give shade – native trees chosen that will never grow too high to compete with their solar panels.
The house’s unique brown siding is made from burnt cedar and treated in the traditional method of Japanese wood preservation – yakisugi. Raiselis used a blow torch to char the wood, then scraped it down with a wire brush to remove the ash and oiled it to enhance the color – producing a unique and durable exterior wood. When this burning process is limited only to the surface coat of the wood, the organisms who feed on this organic matter do not have anything edible left. This burnt seal is why the charred wood is much more resistant to water and the impacts of weather. Raiselis said that it is supposed to last for 80 years with no other treatment necessary.
“We all find this house to be so comfortable. It’s a great house,” she emphasized. “Our boys like the fact that we’re all in this one room, our living space, cooking together, reading, doing computer work at the kitchen table.” She added, “This home represents my dream of combining my architecture and environmental inclinations – it’s a combination of a progressive house-machine and the hand-made. We are trying to make an example; it’s one solution for the future of villages like ours.”
The Ellman/Raiselis passive house residence will be receiving an engineering excellence award in building and technology systems on April 7th in New York City.