http://www.greenhomeguide.com/index.php en john@ducecc.com Copyright 2009 2009-07-06 17:09:09 PDT Copyright 2009john@ducecc.comnoThis is an XML content feed. It is intended to be viewed in a newsreader or syndicated to another site, subject to copyright and fair use. http://www.greenhomeguide.com/index.php/knowhow/entry/1860/ John Messerschmidt is the founder of Four Points Consulting Group in New York City and the Hudson Valley. He specializes in building science and green residential construction. John is certified by the National Association of Home Builders and the National Association of the Remodeling Industry. Question: I am redoing an 84-year-old historic home in Birmingham, Alabama. The house has hardwood floors throughout that need to be refinished. I am trying to find a safe product for staining and sealing these floors and a dealer close to Birmingham. Can you help me? – Charlotte Black, Tuscaloosa, AL Answer: A floor finish that is safe for your health and safe for the earth is easy to find. Any water-based stain and polyurethane will have minimal offgassing of VOCs by the time you move in. If you have the luxury of time, open the windows and let the house air out for a couple of days after the finish has cured. Bona products are low-VOC and durable. They are easy to find, and most flooring contractors are using them. Vermont Natural Coatings has a floor finish that is made with whey protein but still has some VOCs. Finally, AFM Safecoat is a good alternative that is sold widely. But why even use polyurethane? The manufacture of polyurethane products requires enough formulas and petrochemicals and other forms of plastic to make you sick just thinking about it. Why not go authentic? When your house was built, they probably used tung oil to finish the floors. Apply five coats of pure tung oil 50/50 with citrus solvent, and then another three coats with progressively less solvent. Finally, apply two more coats with just tung oil. You'll need long, long drying times in between the last coats, but the resulting finish should last another 84 years. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-07-06 16:09:09 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1859/ John Messerschmidt is the founder of Four Points Consulting Group in New York City and the Hudson Valley. He specializes in building science and green residential construction. John is certified by the National Association of Home Builders and the National Association of the Remodeling Industry. Question: We are renovating a log cabin. Part of the building will have a flat extension that we want to use as a native Virginia sedum-planted green roof. The cabin is surrounded by large oaks and other trees, which attract a lot of squirrels. Do I need to be concerned about constantly weeding the roof of seedlings? Is the sedum going to be attractive to the squirrels? – John Duke, Richmond, VA Answer: In the city, people claim a green roof will save energy, reduce the heat island effect, and prevent stormwater from overflowing the sewers. A cabin in the woods doesn't have the second two problems, and I doubt there would be enough energy savings to justify the expense, so there is no real reason to install a green roof unless you want a real expensive squirrel feeder. I don't know how much green roofs cost in your area, but people are paying $15 to $20 per sq. ft. for them in NYC. Then they have to irrigate them for two years until the plants are established. Rather than planting a green roof, I would install a conventional roof with plenty of insulation. Use two inches of rigid foam on the roof deck, then spray the underside with expanding foam. The most environmentally preferable roofing option is a standing-seam metal roof. They last 25-plus years, and have no petrochemicals as asphalt roofs do. If you don't like the look of a stainless-steel roof on a log cabin, I wouldn't have a problem recommending a small, cabin-size asphalt roof—as long as you take advantage of the renovation and beef up the insulation in your walls, too. Closed-cell spray foam or blown-in cellulose will make your cabin extremely energy efficient, and cozy in the winter. I realize this is a lot of plastic for a cabin in the woods, but if you burn less carbon to heat the place than you otherwise would, maybe the earth will forgive you for using a few asphalt shingles and some plastic foam. If your aim is to save water and encourage local biodiversity, there are other ways to achieve this. Install a rainwater catchment barrel connected to drip irrigation so you don't have to water your yard as much. Maybe you have a local nursery that can recommend native plants and flowers for landscaping. If you dig up the invasives that are already there, chances are native plants will grow back naturally. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, 2009-07-06 16:05:49 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1858/ John Messerschmidt is the founder of Four Points Consulting Group in New York City and the Hudson Valley. He specializes in building science and green residential construction. John is certified by the National Association of Home Builders and the National Association of the Remodeling Industry. Question: We are building a new home and in researching insulation have come across arguments for and against insulating both sides of the foundation. The debate seems to focus on whether insulation on both sides allows moisture to be adequately removed. Can you please provide further thoughts on this and explain the science behind both sides of the argument? – Marci Hess, Madison, WI Answer: There is no reason you can't insulate both sides of the foundation, as long as you only have one vapor barrier on the outside of the foundation. The foundation's concrete floor and walls absorb moisture from the earth. A vapor barrier such as roofing membrane or dampproofing will keep this moisture out of the structure. Insulation is needed to prevent another type of moisture—condensation—from occurring on the warmer side of the vapor barrier, inside the concrete block wall (similar to what happens on a cooler full of ice). The aim is to reduce the amount of condensation and allow the walls and floor to dry to the inside. Here's how to do it: Install 2 inches of rock-wool insulation on the outside of the vapor barrier and foundation walls to reduce the amount of condensation. Then install insulation that does not have a vapor barrier on the inside of the foundation walls. For the floor, I recommend putting 4 inches of insulation under the slab, because you can't put insulation on top of the floor. Frame the walls with 1-5/8" steel studs one inch from the wall and install Bonded Logic cotton insulation. (Leave a 2-inch gap above the floor in case of flooding.) This will further increase your R-value, reduce condensation, and make the walls sound solid and sturdy (not hollow). As long as there is no vapor barrier on the inside, your walls will be able to breathe and dry out. If you're on a budget, I suppose you could use fiberglass insulation, but just know that fiberglass is not an attractive choice environmentally. It is a probable carcinogen and extremely energy-intensive to manufacture. For more information: "Understanding Vapor Barriers," an article from the May–June 2009 issue of EcoHome Magazine, explains the science behind vapor barriers. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-07-06 15:51:53 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1822/ Cameron Habel is founder of Oakland, CA–based Cameron C. Habel Construction, Inc., an award-winning remodeling company. Certified by Build It Green in 2004 as a Green Building Professional, he advises clients and associates on green practices and systems that focus on energy efficiency and resource conservation. Question: We are renovating an old house that never had kitchen cabinets. Is there a manufacturer of kitchen cabinets that is truly green? – Josie Carothers, Harvard, MA Answer: There are several things that I look for in a green cabinet. I look for cabinet boxes free of urea-formaldehyde. Particleboard or fiberboard, such as Medite II, and plywood are acceptable materials, provided they are formaldehyde-free. It's even better if the particleboard has a high recycled content. Medite II is made of 100-percent post-industrial recycled fiber. The solid wood parts of the cabinet and the wood veneers should be FSC-certified, or a rapidly renewable species such as German beech. The cabinet finishes should be of an ultralow-VOC-content material, no more than 150 g/L (grams per liter). (Just because a finish is water-based doesn't mean it's low-VOC.) The adhesives used should also be low-VOC. Find out whether the manufacturer operates its facilities in an eco-friendly manner. Labels to look for include the Composite Panel Association's EPP (Environmentally Preferable Product) Downstream certification and the Kitchen Cabinet Manufacturers Association's Environmental Stewardship Program seal. There are several manufacturers that make green kitchen cabinets. The "Breathe Easy" line of cabinets, made by Greenway Cabinetry in New York State, is available near you at the Green Depot in Stoneham, Mass. GreenQuest, made by Crystal Cabinets in Minnesota, is a fully customizable line of cabinetry that is also truly green. GreenQuest is available in Massachusetts through Crystal Cabinets representative David Landry. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-18 16:14:58 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1821/ Cameron Habel is founder of Oakland, CA–based Cameron C. Habel Construction, Inc., an award-winning remodeling company. Certified by Build It Green in 2004 as a Green Building Professional, he advises clients and associates on green practices and systems that focus on energy efficiency and resource conservation. Question: Are there click-on cork tiles/planks suitable for placement in a bathroom? I am considering linoleum or cork for an area that covers our kitchen, laundry area, and bathroom. I am looking for something affordable and contemporary looking. – Willy Scholten, San Jose, CA Answer: "Click-on" refers to the method of installation: the tongue of one tile clicks into the groove of the adjacent tile. This type of installation is also called a floating floor. Manufacturers do not recommend floating floors for bathrooms or other areas subject to high moisture levels. Instead, you can use a cork tile that is glued down to a properly prepared substrate such as concrete or an approved plywood underlayment. (Cork tile should not be installed over existing resilient flooring such as linoleum or nonporous surfaces such as ceramic tile.) If properly installed and maintained, cork is perfectly suitable as a bathroom flooring. Most manufacturers recommend the application of two to three coats of polyurethane finish to seal the joints and prevent water from getting underneath the tiles. Polyureseal BP, made by Safecoat, is a nontoxic, very low-VOC substitute for traditional urethanes. Another product I recommend is Bona Traffic. Floor wax is also an approved finish material. Be sure to check the manufacturer's installation guidelines before choosing your finishing product. Manufacturers of cork flooring include Expanko, Wicanders, Natural Cork, and Globus Cork. Costs vary widely from manufacturer to manufacturer. Unfinished tiles cost around $4.35 to $4.95 per square foot, while pre-finished tiles cost around $4.95 to $5.95 per square foot. (Even for factory pre-finished tile, you should apply an additional coat of polyurethane onsite to protect the seams from water infiltration.) Installation costs vary around the country. In the San Francisco Bay Area, installation cost (including the material cost of pre-finished tile, but not including the cost of applying additional coats of urethane) is anywhere from $10 to $14 per square foot. You mentioned you're also interested in linoleum. Linoleum is a great flooring choice for a bathroom floor. Unlike cork flooring, it is available in sheets. (It is also available as a tile that can be glued down or a tile that can be installed with the "click-on" method, but again, click-on tiles are not recommended for wet areas.) For extra durability in rooms where the floor tends to get wet, the seams between linoleum sheets can be heat-welded and the edges can be turned up the wall using a method called flash coving. Armstrong and "Marmoleum" are two linoleum products with a great range of colors and style selections, both as tiles and as sheet goods. Installed linoleum costs around $7 to $8 per square foot in the Bay Area. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-18 16:03:06 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1820/ Cameron Habel is founder of Oakland, CA–based Cameron C. Habel Construction, Inc., an award-winning remodeling company. Certified by Build It Green in 2004 as a Green Building Professional, he advises clients and associates on green practices and systems that focus on energy efficiency and resource conservation. Question: Is a solar hot-water heater expensive to put in your home? I think I want to get one, but I'm afraid to put one in. I've heard that the system parts freeze in the winter and are expensive to replace. – Aliya Rodriguez, Olympia Fields, IL Answer: A solar hot-water system is a very efficient way to utilize the sun's energy. Compared to other water-heating methods, it provides the most energy for dollar spent. A solar thermal system consists of solar collector panels on the roof, a separate storage tank (or your water-heater itself can serve as the storage tank), and pipes to distribute the hot water. In Illinois, the system might also include a heat exchanger and pump. The heat exchanger will slightly reduce the system's efficiency. If you install a certified system, it will qualify for rebates and federal tax incentives that will make the system more affordable. The Illinois Department of Commerce and Economic Opportunity sponsors the Solar Rebate Program, which is expected to resume funding in July 2009. The Illinois rebate will reimburse you as much as 30 percent of the installed cost (with a maximum rebate of $10,000). Federal tax credits will also offset as much as 30 percent of the installed costs (with no cap on the amount of the credits). The credits may be carried over in subsequent years. Illinois also offers a property tax incentive so that you will not be taxed on the increased value added to your property by the solar system. Initial costs vary widely depending on which kind of system is installed and on the size of the system. That said, based on cost tables provided by the ACEEE (American Council for an Energy-Efficient Economy) consumer guide, the installed cost for a typical system with electric backup might be $4,800. With rebates and tax credits the net cost might be $1,920. If your water-heating costs are cut in half, you might save $175 per year, depending on whether you currently heat your water with gas, oil, or electricity. Not including maintenance costs or cost increases for energy, the system would pay for itself in about 11 years. After the payback period, you accrue savings over the life of the system, which is anywhere from 15 to 40 years. Paybacks vary widely. Generally, payback periods are shorter in areas with higher energy costs, areas with a greater number of sunny days, and areas that do not experience winter freezes. To address the second part of your question, a properly designed and installed system will not freeze. In places like Illinois that are subject to prolonged freezes, an "indirect" or "closed-loop" system is often installed. This system makes use of a type of antifreeze that is heated by the sun. A heat exchanger transfers the heat in the antifreeze to the water system for use in your home. The antifreeze protects the solar heating system from freezing. "Direct systems," which don't use antifreeze, use flush-type valves to protect the system from freeze damage. Before the water approaches the freezing point, the flush valve opens, purging the water from the system. Other system designs use a pump to circulate warm water from the storage tank to prevent the system from freezing. Solar thermal systems also utilize devices to prevent damage if the system gets too hot. Solar thermal systems are certified by independent agencies and are given a thermal performance rating. You can use certification listings from the FSEC (Florida Solar Energy Center) or SRCC (Solar Rating and Certification Corporation) to compare different systems. Look for the Florida Energy Factor (FEF) in the FSEC ratings tables or the Solar Energy Factor (SEF) in the SRCC ratings tables. The higher the number, the more efficient the system. A typical system has a SEF between 1 and 2. For more information: The Midwest Renewable Energy Association is a good resource for information about renewable energy in the Midwest region. The U.S. Department of Energy's website offers tips on how to estimate the annual operating cost of a solar thermal water-heating system. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-18 15:45:11 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1815/ Paul Gleicher is a LEED Accredited Professional and Registered Architect. He is the founder of New York City–based Gleicher Design Group, a multidiscipline design firm offering eco-friendly architecture and interior design services. Mr. Gleicher was a featured presenter at the recent Architectural Digest Home Design Show, and is coauthor of Dreaming Green: Eco-Fabulous Homes Designed to Inspire. Question: We are remodeling our main bathroom. I would like to install a "green" floor. What would be the most durable and easy-maintenance option? How about linoleum? – Kathleen Schaeffer, Easton, PA Answer: Several options come to mind for bathroom floors. When it comes to durability and easy maintenance, I find porcelain tiles and ceramic tiles to be great solutions. Imagine Tile makes unique ceramic tiles: they emboss a photographic image on the face of the tile, creating wonderful design opportunities. The components they use are all-natural (i.e., earth minerals and ores) and environmentally safe. Images such as rocks, water, and flowers are available, or you can create a custom image. As for porcelain tiles, the Italian company Atlas Concorde makes amazing products. The company has obtained the European Union's Eco-label certification for all its porcelain collections. I suspect, however, that you are looking for a more resilient floor that is not as hard underfoot as porcelain or ceramic tile. Linoleum is a wonderful choice in that regard. It is manufactured from primarily natural raw materials including linseed oil, rosins, and wood flour applied to a jute backing. Forbo makes a product called Marmoleum Click which employs a linoleum topping over a cork backing. Each board is "snapped" into its neighboring tile, and thus no glues or adhesives are required for installation. This can be a major benefit, as it is the adhesives that can offgas into your home, resulting in unhealthy indoor air quality. That being said, for a bathroom application, I recommend using linoleum sheets rather than tiles so as to reduce the number of seams in the flooring. These seams are the weak points in the system where water can enter. It is therefore important to apply a bead of silicone around the tub, shower, toilet, and sink where they meet the floor to protect against water infiltration. Not only is the linoleum floor durable, but it is also antimicrobial and its antistatic properties make it easy to clean with just a damp mop or a dustmop. Another nice quality of the linoleum is that you can walk on it without your feet being cold. It is important to consider the social and environmental policies of the manufacturer, and Forbo takes great pride in its state-of-the-art processes to protect the environment, recycling waste whenever possible and keeping emissions to an absolute minimum. Linoleum products generally run about $10 to $15 per square foot to furnish and install. Another wonderful product to consider is IceStone. This company, based in Brooklyn, NY, mixes glass from recycled bottles into a cement substrate to create 1¼-inch-thick slabs similar to granite. It is quite beautiful, very easy to maintain, and extremely durable. The manufacturer is a socially and environmentally responsible company, employing healthy labor policies and housed in a fully daylighted factory. I have used IceStone for a shower-stall floor by sanding it down to remove the gloss finish so it is not slippery when wet. (I don't think sanding would be necessary for a bathroom floor that stays dry, such as a powder room.) This product is a more expensive option, as its pricing is similar to granite, ranging from $60 to $70 per square foot to furnish and install. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-12 10:37:31 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1814/ Paul Gleicher is a LEED Accredited Professional and Registered Architect. He is the founder of New York City–based Gleicher Design Group, a multidiscipline design firm offering eco-friendly architecture and interior design services. Mr. Gleicher was a featured presenter at the recent Architectural Digest Home Design Show, and is coauthor of Dreaming Green: Eco-Fabulous Homes Designed to Inspire. Question: What do you know about on-site wastewater treatment? I heard that the Solaire apartment building in Battery Park has a "membrane bioreactor" that treats wastewater so it can be reused. Is that type of thing cost effective? Also, what is the average cost of green-roof installation in New York? I would like to know more about green roofs and what incentives are available to reduce the installation costs. – Cesar Yoc, New York, NY Answer: First, let's clarify the term wastewater. There are two categories of wastewater: blackwater and graywater. Blackwater contains human and food wastes, and is not easily reused. Sources of blackwater include toilets, urinals, kitchen sinks, and dishwashers. Graywater is wastewater that has been used in clothes washers, showers, bathtubs, and bathroom sinks. Because it does not contain human and food wastes, it can be more easily stored and reused for outdoor irrigation. Typically a separate drain-piping system is created for collecting the graywater. The graywater system's piping must be clearly marked so that it is distinguished from the potable water system, to prevent any chance of contamination through mixing of the two systems. The graywater is filtered and then temporarily stored. Later it can be used to flush toilets, or it can be distributed in subsurface outdoor irrigation. Not only does this divert water that would normally be sent to the sewage treatment plant, it also reduces the expense of your irrigation system by reusing water you've already paid for. Graywater systems for an entire building are worth considering when there are outside landscape areas where it is feasible to use subsurface irrigation. But graywater systems can be rather expensive, and they are not simple to put in place. As water shortages or drought conditions become more prevalent, these relatively complex and expensive systems will become more feasible, and we will be motivated to install them based on relieving these conditions rather than just for financial returns. Green roofs Green roofs help counteract the Urban Heat Island Effect, a phenomenon in which urban centers become significantly warmer than surrounding rural areas as a result of the covering of natural land masses with concrete or asphalt. By covering asphalt roofs with a blanket of live vegetation, a more natural balance is attained, helping to reduce the average temperature in the city. Green roofs can also absorb up to 80 percent of a heavy rainfall. This is significant because our sewer systems are combined with our stormwater systems, so when there is a heavy rain, all the rainwater overtaxes the sewage treatment plant, resulting in raw sewage being dumped into waterways. Green roofs help reduce the cooling load placed on a building by reducing the amount of solar gain on the building during the summertime. Another benefit is that they filter pollutants and carbon dioxide out of the air (not to mention that they look great). Green roofs come in two varieties: intensive and extensive. An intensive green roof requires much more soil depth than an extensive green roof and, as the name implies, requires more intensive efforts to maintain, including feeding and irrigation. Deeper soil enables the growth of large plants or conventional lawns, even small shrubs or trees. An intensive green roof weighs appreciably more than an extensive green roof and may require significant upgrading of the underlying structural support of the building. On the other hand, extensive green roofs are only about three inches thick, thus much lighter (about 15 pounds per square foot when fully saturated). They perform much better in drought conditions than in wet conditions. After the initial installation has stabilized, which usually takes about a month, watering should really be kept to a minimum. Extensive green roofs are virtually self-sustaining, relying on natural rainfall to fit the bill. Extensive green roofs are comprised of several layers on top of a waterproof roof. (I particularly like the system from XeroFlor.) You start with a root barrier installed directly over the waterproofing membrane. This barrier prevents plant roots from compromising the building components. Above this barrier, a drainage mat of non-woven nylon filaments fused to a geotextile particle barrier allows surface flow beneath the vegetated layers. Then a water-retention fleece is applied, followed by a growing medium of lightweight aggregate. Finally, a pre-planted mat containing sedum and moss vegetation completes the installation. A green roof system costs, on average, about $15 to $25 per square foot in New York City. I recommend most homeowners stick with the extensive systems. They are much simpler to install and maintain, and they weigh much less than an intensive green roof, so you do not necessarily need to add expensive structural supports. Last August, Governor David Paterson signed into law a bill (A.11226) that provides a tax abatement for construction of green roofs in New York City. Under this law, a New York City building owner can receive a property tax credit of $4.50 per square foot of green roof, or about one quarter of the roof's cost. In order to obtain the abatement, construction of any green roof must have begun on or after August 5, 2008. The application for the abatement must be signed and sealed by a licensed architect or engineer, and must include signed and sealed drawings and a three-year maintenance plan. For more information, please refer to the websites of the NYC Department of Buildings and the S.W.I.M. (Storm Water Infrastructure Matters) Coalition. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-12 10:27:08 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1813/ Paul Gleicher is a LEED Accredited Professional and Registered Architect. He is the founder of New York City–based Gleicher Design Group, a multidiscipline design firm offering eco-friendly architecture and interior design services. Mr. Gleicher was a featured presenter at the recent Architectural Digest Home Design Show, and is coauthor of Dreaming Green: Eco-Fabulous Homes Designed to Inspire. Question: We are planning on building a green home about a year from now. Are there references available that would help us get started? – Margaret Vanwormer, Great Mills, MD Answer: First of all, let me applaud you for your desire to build green. My wife and I were in a similar situation several years ago, right after we purchased a townhouse in the city that we wanted to renovate responsibly for our family. The house dated from 1885 and had fallen on hard times, not to mention that it was filled with toxins such as lead and asbestos. At that point in time we found it very difficult to find sources of information for how to go green. To learn more about green products, we spent many hours going to trade shows such as the ICFF (International Contemporary Furniture Fair) and the Architectural Digest Home Design Show, asking each vendor if they offered anything green. Visiting trade shows in your area is a good way to see what's available up close and personal. For those of you who live near New York, GreenBuildingsNY is coming to the Javits convention center in the middle of June. New Yorkers can also check out new products at GreenDepot in Manhattan. It's essentially a retail store similar to Home Depot, but its emphasis is on green products. We also searched the Internet and bookstores for resources to use in renovating our home. I pored over the GreenSpec Directory, a publication from BuildingGreen.com. The directory includes hundreds of products that they have investigated. It's organized by the various components of a building: concrete, masonry, metals, woods, paints, plumbing, appliances, etc. Ultimately, after our house was completed, we embarked on writing our own book, Dreaming Green: Eco-Fabulous Homes Designed to Inspire. It is a coffee-table book covering 17 homes from across the United States. Each chapter covers one home, listing the top ten green features in each home. At the back of the book, we list over 200 resources, for easy access to many of the items that are depicted in the book. Fortunately, there are a lot more resources now for learning how to build a green home. I strongly recommend that you visit some of the many websites dedicated to building green. In addition to GreenHomeGuide.com, among the best are: GreenBuildingAdvisor.com: This site offers insights on a multitude of green building and remodeling projects for kitchens, bathrooms, home offices, etc. The "Green Basics" section includes a green building encyclopedia. Another useful feature is the overview of Integrated Design, which is the process of designing and building a house holistically from the beginning, rather than treating each piece of the puzzle as an island unto itself. GreenBuildingTalk.com: This site includes forums and discussion groups on green topics such as radiant heating, insulating concrete forms (ICFs), geothermal heat pumps, and solar and wind power. Finally, it is never too soon to meet with a design professional to start discussing your options. You will need to consider how to situate your home on the property to take advantage of passive solar gain, how to maximize water efficiency, and what energy conservation methods (and/or alternative energy sources) you may employ. A green professional can offer advice on researching responsibly manufactured materials that will create a safe environment and healthy indoor air quality for your new home. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, 2009-06-12 10:05:59 PDT http://www.greenhomeguide.com/index.php/knowhow/entry/1794/ Daniel Glickman is the owner and general manager of Sustainable Construction Services, Inc., a residential green design/build company in the Boston area. Daniel is a Certified Remodeler and a Green Certified Professional by the National Association of the Remodeling Industry. Question: What sort of ductwork do you consider safe? We have flexible heating ductwork and we found out recently that it's lined with PVC. What would you recommend as a replacement? – Sandy Van Wagoner, Auburn, WA Answer: Rigid sheet-metal ducts are a far better choice than flexible plastic ducts for efficiency, durability, and health reasons. Efficiency Flexible ductwork really reduces airflow because of the turbulence created by the textures and corrugations on the interior of the duct. In many cases, flex-duct is used improperly as a shortcut for tough install conditions; it is twisted and squished in tight spots, creating bottlenecks and flow restrictions. Proper rigid sheet-metal ductwork is straight and smooth so air flows well. Using 45-degree angles rather than 90-degree-angle connectors on the install will further increase efficiency. It is also very important to properly seal sheet-metal ducts with mastic to prevent air leaks. Durability Flexible vinyl ductwork rips easily and many types of flex-duct may become permanently squashed if pressure is applied. Flex-duct also degrades under stressful conditions; for this reason, in many states, these types of ducts are not approved for exhaust ducting. Health A flexible duct with twists and bends and a rough interior surface will accumulate dust and other particles. Add some moisture to the stew and you have a breeding ground for all kinds of nasty stuff. You indicate that you are concerned about PVC (polyvinyl chloride, or vinyl). The PVC used in some types of flex-duct does have an environmental impact, but when it comes to indoor air quality, I believe the microbes fostered by flex-duct are more of a concern than the vinyl. GreenHomeGuide's Ask A Pro archive has answers to dozens of other green home questions from our network of the best and brightest green architects, designers, contractors and consultants across the U.S. {category_name backspace="1"}, {category_name backspace="1"}, 2009-05-28 10:42:00 PDT nonadult