Green Roofing OptionsDavid JohnstonTo determine what makes a roof green, we must first consider what a roof does. First, a...
Lead-free metal roofing. Metal roofing is made from copper, steel or aluminum. Some productscontain up to 100 percent recy...
Cedar shake. Many in the greenbuilding industry discourage the use of cedar shake because thecedar is often harvested unsu...
However, these multilayered green roof systems are thicker and heavier than conventional roofs.Therefore, the roof structu...
Greener Roofing OptionsBy Claire Anderson and Scott HollisBuilders have always said “a good hat and good shoes” are essent...
reflectivity maintain a more even core temperature, which protects against the shingles’deterioration.“Cooling-load avoida...
Disadvantages include its heavy weight and its high initial cost. Tile roofs can easily cost two tothree times more than a...
and concrete areas — such as in cities — to build up more heat than the surroundingcountryside) also are reduced, as is st...
such as a garden shed or gazebo. For do-it-yourselfers, McGhee sells inexpensive, “shaggy”thatch mats at less than $5 per ...
The last word in eco-friendlier roofs may be the introduction of photovoltaic (PV) roofing shinglesand thin-film laminates...
The Slate Roof Bible, by Joseph Jenkins, gives an in-depth look at slate roofing through the ages,and provides complete in...
stained ceilings and peeling paint can result. If moisture infiltrates attic insulation, it can reducethe insulative abili...
Recommended Books:Natural Remodeling for the Not-So-Green House: Bringing Your Home into Harmony withNature (Natural Home ...
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Green Roofing Options; by David Johnston

  1. 1. Green Roofing OptionsDavid JohnstonTo determine what makes a roof green, we must first consider what a roof does. First, andprimarily, roofs keep rain (and snow) off our heads and off the walls of our houses; second, theykeep us safe from fire; third, they add to the curbside appeal of our homes; fourth, they collectwater for landscapes; and finally, roofs provide temperature abatement.Ideally, green roofing materials, which are better for our health and for the environment, wouldprovide all five of these benefits. But its not always that simple. Often roofing that works well inFlorida is not a good option for a home in Colorado. Roofing is one of the most climate-specificmaterials for building, so you need to prioritize your requirements and make decisions based onwhat you want a roof to do for your home.COMPARING ROOFING OPTIONSWhen choosing a roofing material, its important to consider all the options available, as well asyour climate, your homes requirements, and health and environmental issues. Some roofingmaterials contain carcinogens that can affect the health of a homes occupants. Another concernis re-roofing, which accounts for 78 percent of the total annual roofing dollars spent in the UnitedStates. Re-roofing is not only expensive, but can send used roofing materials to landfills, wherethey can off-gas pollutants and leach toxins into the soil and groundwater.Heres a quick rundown on todays roofing options with recommendations on which ones might bebest for your home:15-year asphalt shingles. For numerous reasons, this type of roofing material is not a goodoption. Short-lived asphalt shingles are a bad use of oil and are rarely recycled. They are amongthe most disposed-of building materials. Toxic volatile organic compounds (VOCs) will off-gasfrom asphalt as the sun heats it; these VOCs can then enter the living space through doors,windows and vents.50-year recycled-content asphalt shingles. At the very least, look for recycled-content asphaltshingles that contain recycled or reclaimed-material slag in their aggregate surface, therebyreducing waste of raw materials during the roofing process. This inexpensive, hail-rated roofingmaterial will last 50 years instead of 15, resulting in less waste sent to landfills and minimizing thehassle of roof replacement. For any type of asphalt shingle, never drink water that comes off theroof or use it for any type of water catchment.
  2. 2. Lead-free metal roofing. Metal roofing is made from copper, steel or aluminum. Some productscontain up to 100 percent recycled material, and most can be easily recycled. Metal roofing iseasy to install, and it is fireproof, lightweight and long lasting. Also, unlike all other roofingmaterials, metal roofs provide rigidity. Metal is the most favorable roofing material used forrainwater catchment systems. In northern climates, snow readily slides off metal roofs, preventingdamage caused by ice dams. Metal roofing comes in many shapes and styles, including panels,shingles, shakes and tiles, as well as a wide range of colors and patterns. Because the metal isthin and does not have heat-holding capacity, metal roofs do not radiate as much unwanted heatinto the attic as asphalt shingles. Using a white painted or galvanized finish on the metal willfurther deflect heat away from the roof and attic. On the downside, metal roofing can beexpensive.Fiber-cement composite roofing. Fiber-cement is made of Portland cement, sand, clay and woodfiber. The product typically carries a 50-year warranty. Fiber-cement composite roofing is durable,fireproof and recyclable. This roofing material can be readily used on standard roof structures.Fiber-cement composite slates or shakes are not recommended in northern regions or at highaltitudes because they do not perform well in freeze-thaw climates or in hail-prone areas. Keep inmind that you cannot walk on fiber-cement roofing, and it can be difficult and expensive toreplace.Clay tile. Clay tile is durable, attractive and very popular in places like California and theSouthwest. The corrugated design has a cooling effect on the roofing system, since air is able toflow around it. However, hail can shatter clay tile, so it is not the best option for northern climates.Its also fairly expensive. You cannot walk on it to repair it easily, and it does not work well withsolar applications.Cast-concrete tiles. Cast-concrete tiles are fire-resistant and look similar to fiber cement roofing.However, they are heavier than fiber cement, so extra structural work is required. Their colortends to fade over time, and freeze-thaw cycles can damage the tiles unless they are specificallyformulated to withstand it. The tiles tend to shatter in hail and are expensive to buy and install.Slate. Slate is minimally processed cut or split rock. It creates a distinctive look and is incrediblydurable. Not only does it have a good fire rating, but properly installed slate roofs can last 100years or more with only minor maintenance. Whats more, it can easily be reclaimed and reusedon new building projects. Keep in mind that slate comes only from mid-Atlantic and Northeasternstates, as well as from Europe; therefore, depending on where you live, transportation costs canmake the material expensive.
  3. 3. Cedar shake. Many in the greenbuilding industry discourage the use of cedar shake because thecedar is often harvested unsustainably. Although fire-resistant coatings do exist for cedar shakeroofing, in general it is a serious fire hazard, making it an expensive option, if not illegal in manyareas.Recycled synthetic shingles. These expensive recycled rubber and plastic shingles offer analternative to such roofing materials as cedar shingles and shakes, natural slate, clay or concretetiles and standing-seam metal roofs. Attributes include durability (guarantees range from 40 to 50years), excellent hail and wind resistance, and good seismic and sound insulation performance.Insurance companies in several states have responded to their superior hail and wind resistanceby offering discounts to homeowners who install recycled synthetic shingles.EPDM rubber. EPDM (ethylene propylene diene monomer) rubber is one of the most commontypes of low-slope roofing material in the United States, primarily because it is relativelyinexpensive and simple to install. During and after installation, it doesnt release odors and fumes,as some other types of roofing materials do, which appeals to many homeowners.Modified bitumen. Modified bitumen is asphalt that has had modifiers added to it to give it plasticor rubber-like properties. This fairly sophisticated roofing material comes in rolls and is primarilyused for slope roofing.Hot asphalt. Although its inexpensive, durable and easily repaired, this is not a great roofingmaterial. Again, its a bad use of oil, the installation process is highly toxic and it requires frequentmaintenance to prevent ultraviolet sunrays from breaking it down.Building-integrated photovoltaics (BIPV). These new roofing systems are coated with a film thatconverts sunlight into electricity. The shingles or tiles snap together, and the electrical currentflows at the edge of the roof. The shingles look like slate or can be applied to standing-seamsteel. After the roofer installs the tiles, an electrician connects the roof system to the homeselectrical system. Each 100 square feet of BIPV generates about 1 kilowatt of electricity, which isnot that much relative to solar panels, making it an expensive form of solar electricity.Green roofs. As the name implies, these truly "green" roofs are planted with vegetation. Alsoknown as "living roofs," they are protected-membrane roofs with soil and plantings (as well asinsulation) installed above the membrane. These systems are encouraged and even subsidizedin Europe because they reduce flooding risks and cooling needs. They can detain over half therainwater from a typical storm, reducing often-high loads placed on sewer systems after rainfall.In addition, a green roof can be a wonderful architectural element that absorbs carbon dioxideand helps reduce building heat gain and urban heat islands.
  4. 4. However, these multilayered green roof systems are thicker and heavier than conventional roofs.Therefore, the roof structure needs to be engineered to accommodate the increased weight of theroof. It must also be watered intensely, and its expensive.As you can see, choosing the right roof for your home can be a complicated process. But byevaluating all the options available, considering your location and climate, and keeping in mindhealth and environmental concerns, you can make sure your final selection is a wise one.Kim Master is a senior associate at Whats Working Inc., a Boulder, Colo.-based greenbuildingconsultancy. David Johnston is the founder of Whats Working. Theyre the authors of GreenRemodeling: Changing the World One Room at a Time (New Society Publishers). This article hasbeen posted in its entirety from the July/August 2006 issue of Smart Homeowner.
  5. 5. Greener Roofing OptionsBy Claire Anderson and Scott HollisBuilders have always said “a good hat and good shoes” are essential to protect a house from anytype of weather. Even so, home builders opt to install the cheapest, shortest-lived shingles onfour out of five new homes built in the United States today.“‘First cost’ is the overriding issue in most home building,” says Alex Wilson, executive editor ofBuildingGreen, publishers of Environmental Building News and Green Building Products.“Builders are trying to get the most house for the least money. And most homeowners havebought into the idea that they should build or buy the largest house they can afford.oing so meansthey cut corners on the material’s durability and performance.”Incorporating green building materials into your home makes much more sense when you take along-term view of home building and its life cycle costs. Only then is it apparent that building withbetter roofing materials is in your best interest. And now, eco-friendlier roofs are more attractive,affordable, durable and readily available than ever.Criteria to ConsiderNot all roofing material is created equal. Each has attributes that best suit certain structures andenvironments. Choosing the right product for your home involves a careful analysis of suchfactors as durability, solar reflectivity, cost and ecological impact. If you have considered re-roofing your home or are planning to build a new house, weigh these criteria before selecting aroof material.First, consider the roof’s durability: How long will it last? Some asphalt shingles are inexpensiveto buy, but they have half (or less) the life expectancy of many other roofing materials. But higher-quality asphalt shingles can be a viable option if properly chosen, says Clarke Snell in his book,The Good House Book: A Common-Sense Guide to Alternative Homebuilding. “Poor qualityasphalt shingles ... are the Styrofoam cup of the building industry, [but] high-quality asphaltshingles are much cheaper than metal, easy for one person to install, accommodate roofpunctures such as chimneys and skylights with relative ease, and can last 30 to 40 years ormore.” The moral here is that even the same product type can have a wide range of quality, so besure you know what you’re getting before you buy.Another consideration when choosing a new roof is the material’s solar reflectivity, known as thealbedo. If you are planning to retrofit an older home with a greener roof, its albedo may be agreater concern than a newer house with efficient insulation. Use of lighter colored, low solar-absorbent roofing surfaces is one of the key measures advocated in the “Cooling OurCommunities” program of the U.S. Environmental Protection Agency (EPA).Studies conducted by the Florida Solar Energy Center compared the performance of roofingmaterials. Asphalt shingles had a solar reflectance ranging from 3 percent (onyx black shingles)to 31 percent (“white” shingles). Brown wood shingles were found to have a solar reflectance ofabout 22 percent, and a brownish-orange terra-cotta cement tile had about a 24-percent solarreflectance. In contrast, white and light-colored metal roofing had reflectances ranging from 50percent to 66 percent.Improving the albedo of your roofing surface can cut cooling costs by up to 50 percent, dependingon how much insulation is in your ceiling or roof. And, while you save on cooling costs, you’ll alsoprolong the life of your shingles. According to, roofs with high solar
  6. 6. reflectivity maintain a more even core temperature, which protects against the shingles’deterioration.“Cooling-load avoidance can be important in some situations,” Wilson says. “But if a house isproperly insulated to at least R-24 [the higher the R-value, the lower the heat flow] in the ceiling orroof, the heat gain or heat loss through solar energy absorption on the roof surface is really prettyminor. With the insulation levels recommended in a green home, albedo is not a significantconsideration.”Asphalt OptionsAccording to the Asphalt Roofing Manufacturers Association, more than 12.5 billion square feet ofasphalt shingle products are made each year — enough to cover more than 5 million homesannually.The attraction to asphalt shingles is they are affordable and lightweight — no additionalengineering is needed to put them on your rooftop. Of all the roofing products available, theyusually are the least expensive upfront, but proportionately less durable over time.“It’s a hard sell to push homeowners to longer-lasting alternatives because those alternatives areusually a lot more expensive, and the homeowner probably doesn’t expect to stay in a house formore than 20 years,” Wilson says.“Asphalt is a bad roofing option from an environmental standpoint,” Wilson adds. “In addition to allthe resources going into making such a short-lived product, there is a tremendous amount of solidwaste generated from the removal of old shingles.”Every year about 11 million tons of asphalt shingles are shucked into landfills, according In fact, old asphalt shingles constitute about 3 percent of all municipalsolid waste. Asphalt shingles can be recycled, but so far the technology to do so is in its infancy,and widespread asphalt shingle recycling is not available.Asphalt shingles come in two different kinds: organic-based or fiberglass-based. The organic kindare made from materials such as recycled waste paper, wood fibers and felt, then saturated witha specially formulated asphalt coating and surfaced with weather-resistant mineral granules.Organic-based asphalt shingles contain about 40 percent more asphalt per square (100 squarefeet) than fiberglass, which gives them more weight, durability and blow-off resistance. Fiberglassshingles start with a glass-fiber reinforcing mat that is coated with asphalt and mineral fillers foradhesion, then embedded with ceramic granules. Asphalt shingles come in many differentshapes, sizes, thicknesses and grades. If you do choose to use asphalt, make sure to pick themost durable shingle that suits your structure’s needs, usually an organic variety.Clay-tile RoofsMade from abundant raw materials, ceramic-tile roofs are one of the longest-lasting roofingmaterials available. “Fifty years is nothing for a tile roof,” says roofing restoration expert JosephJenkins of Barkeyville, Pa. “Fifty years is a young tile roof.” In fact, tile roofs can easily last formore than 100 years, often outlasting the buildings they protect. Because of this, they often areconsidered “recyclable roofs” for their ability to be removed and installed on other buildings. Claytile also is coveted for its high resistance to wind and fire, low maintenance and ease of repair.
  7. 7. Disadvantages include its heavy weight and its high initial cost. Tile roofs can easily cost two tothree times more than an asphalt shingle roof, but the initial expense will pay off in many years ofhassle-free roofing.Out of the woodsGenerally split from Western red cedar, Alaskan yellow cedar and Eastern white cedar logs,wooden shingles are available in a variety of shapes and sizes. They have an estimated life of 25to 30 years in dry climates, and 10 to 15 years in moist climates. Wooden shingles allow the roofto “breathe” and release water vapor, provided they are laid over a subsurface that allows for aircirculation behind the shingle.While the rustic beauty of wooden shingles is obvious, they do have their drawbacks. “I am not afan of wooden shingles,” Wilson says. “The raw materials are typically not sustainably produced,and the durability is fairly short, particularly in wet climates.”Moist climates will promote mold, rot, mildew and fungus growth, and arid climates will result inwarping and cracking over time. The initial cost also can be high — twice as much or more asasphalt shingles. Wooden shingles may not be suitable for use in fire-prone areas. Check withyour local building code official first.According to the Center for Resourceful Building Technology, the wooden shingles predominantlyfound on the market are from old-growth forests. For homesteaders with the ability and theresources, hewing your own wooden shingles from already fallen local timber is a viablealternative.Step Up to SlateSlate stone roofs are perhaps the most durable of all roofing materials. They also are strong,available in a color spectrum from sea green to earthy red, and are quite beautiful. Tiles can bemade in almost any shape, and they can be installed on roofs in a variety of thicknesses, widthsand lengths.Slate can weigh 6 to 7 pounds per square foot, which may require additional structural support foryour home or building. The minimum slope for a slate roof is a ratio of 4:12, Jenkins says, but thebest use for slate roofing is for steep slopes. Like clay tile, slate also can last long past the life ofthe building — making it extremely recyclable — and it is initially more expensive than many otherroofing materials, but less expensive when comparing the long-term cost over a roof’s life.Slate can last almost indefinitely, depending on the type, thickness, fasteners, roof slope andinstallation, with only minor maintenance. With the right tools and a little know-how, installing orrepairing a slate roof is fairly straightforward. Reclaimed slate also is available.“By recycling a slate roof yourself, you can own a lifetime stone roof for less money than thecheapest of asphalt roofs,” Jenkins says. “If you’re not that industrious, you can buy new or usedslates and install them yourself with the proper guidebook and tools.” Professional slate-shingleinstallation also is widely available.Under the EarthLiving roofs, covered with a dense mat of growing plants, are sprouting up on the tops ofcommercial and residential buildings in the United States as a way to reduce heating and coolingcosts, and to improve local air quality. Urban heat-island effects (the tendency for large asphalt
  8. 8. and concrete areas — such as in cities — to build up more heat than the surroundingcountryside) also are reduced, as is storm-water runoff. Living roofs can detain more than 50percent of rainwater from a typical storm, which reduces the loads placed on storm sewers inurban areas, according to Green Building Products.Also referred to as a “green roof,” a living rooftop usually consists of a waterproof membrane,such as a modified asphalt or synthetic rubber (EPDM), over the roof sheathing. Next, a rootbarrier and drainage media are placed. On top of the drainage media, 2 to 6 inches of a plantingmixture (lightweight aggregate, sand, organics, clay and silt) are laid. This soil structure supportsdrought-tolerant plants such as succulents, herbs, forbes, grasses and some low groundcovers.Due to their weight and need for solid structural engineering, living roofs are better suited to newconstruction, rather than retrofits, although a structural engineer can help you determine thefeasibility of your existing building structure for supporting a living roof. Water will add another 10to 25 pounds per square foot when the living roof is saturated, so this roofing method shouldn’t betaken lightly. Weight requirements (including snow, where applicable) need careful considerationwhen a suitable roofing structure is designed for holding up all that earth.Living roofs are now available from a handful of suppliers for either commercial or residentialapplication. The Green Products Directory lists U.S.-based companies that specialize in this area.One of the problems with living roofs is what to do if they ever spring a leak. Tracing the leakback to its origin can be a time-consuming exercise in frustration, and solving the problem mayrequire some professional consultation and careful excavation.Grass roots roofsThatch roofs, made with the dry, coarse stems of reeds or grain crops, have been commonplacewherever these materials exist for thousands of years.A common misconception is that thatch absorbs large amounts of water. In fact, in a thatchroofing system water is transferred down the roof from stem to stem until it drops. The steep pitchusually (at a ratio of 12:12) associated with thatch roofs allows for water to be shed at a very fastrate, according to the Building Conservation Directory (www.building, a Website dedicated to the conservation of historic buildings.Besides being water-resistant, thatch roofs are wind-resistant. And, because of the thousands ofair pockets between and within the plant material, thatch also is a good insulator, providing a R-value of about 40.Fire can be a concern, however, and thatcher Colin McGhee of Staunton, Va., says that tocomply with fire codes on public buildings, his company treats its thatch with an odorless,nontoxic fire retardant. “But thatch, as it’s used in roofing applications, is inherently very fireresistant,” McGhee says.Thatch reed roofs are long-lasting, with life spans estimated between 50 and 100 years, ifconstructed and maintained properly, McGhee says. “Every 12 years or so, thatch roofs need abrushing and dressing off, and the ornamental ridge replaced. I’ve worked on [thatch] roofs inEngland that are more than 100 years old and still going strong.”But at a considerable price per installed square foot, most of us don’t have deep enough pocketsto roof our houses with thatch. If you’re entranced with thatch, consider tackling a smaller project
  9. 9. such as a garden shed or gazebo. For do-it-yourselfers, McGhee sells inexpensive, “shaggy”thatch mats at less than $5 per square foot.Recycled RoofsThe rise in popularity of green building has produced a large variety of recycled roofing materials,ranging from rubber shingles to imitation slate tile made from recycled plastic and waste-woodcomposite. Known as polymer-composite or synthetic roofing, these products have the advantageof being lighter than clay tile or slate. Their inherent flexibility makes them resistant to haildamage, high winds and even occasional foot traffic. Made primarily of synthetic materials, theyalso resist organisms that promote decay. Most polymer roofing materials carry 40- or 50-yearwarranties, but also carry a high initial cost, often about $3 per square foot.Panelshake roofing panels, molded from a mixture of old milk jugs and waste-wood fibers, mimicthe look of natural slate and tile roofs. Another composite roofing product, Enviroshake, combinesreclaimed materials such as recycled plastic, agricultural flax- and hemp-fiber waste and a little bitof post-consumer recycled tire rubber. Touted as an alternative to traditional cedar shakes,Enviroshakes incorporate UV protection with excellent mold-, mildew- and insect-resistantproperties. Once installed, they are almost maintenance-free. By using 60-percent to 70-percentrecycled tire rubber, Euroslate moves rubber from the road to your roof. And as an interlockingroofing system, Euroslates offer a similar look to slate.Although polymer-composite roofing offers some environmental benefits up front, noinfrastructure exists currently to support the reclamation and recycling of these materials at theend of their useful lives. Robert Falk, Ph.D., one of the original designers of the product, says heeventually would like to see a buyback system put in place to promote the return of usedcomposite building materials to companies for re-manufacture.Fiber-cement shingles, made by blending Portland cement with finely ground sawdust (fromrecycled sources), sand and clay, are another composite product. Known for their durability inwarmer climates, they typically carry a 50-year warranty. Unfortunately, fiber-cement shinglesabsorb water, which may weaken the shingle due to freeze-thaw cycling in cold weather. Someproducts, however, have coatings or polymer constituents to minimize water absorption.Metal RoofsMetal roofing can be made with up to 25-percent recycled steel from scrapped automobiles. Thisform of roofing is the lightest medium available, weighing a fraction of slate or clay tiles.Additionally, metal will not rot or crack, is noncombustible and designed to resist hurricane-forcewinds. Metal roofing also reflects more radiant sunlight than it absorbs, which saves you moneyon heating and cooling, and it comes in a wide spectrum of materials: steel, stainless steel,aluminum, copper and zinc alloys. Each has different properties that affect durability, price andappearance. Prices range from about $1.80 to $6 a square foot, which may seem expensive, butits long life, minimal maintenance and reduced installation labor makes it proportionatelyaffordable over the long run. It’s lightweight and durable, with a life expectancy of 20 to 50 years,and you can sheet right over an existing roof with it.Metal roofing does have a few drawbacks. Some types of metal roofing such as aluminum makemore noise during rain or a hailstorm and can dent. Long-term issues include paint finishes thatcan peel, chip, fade or scratch.Photovoltaic Roofs
  10. 10. The last word in eco-friendlier roofs may be the introduction of photovoltaic (PV) roofing shinglesand thin-film laminates that both serve as a protective roof cover and energy powerhouse. Whenthe sun strikes the solar cells embedded in the their matrix, electricity is produced. These types ofshingles may even produce power on partly cloudy days. According to the National RenewableEnergy Laboratory, solar shingles provide the same durability, flexibility and protection as asphaltshingles. Most are warranted to produce power for at least 20 years.United Solar Ovonic’s Uni-Solar shingles incorporate directly onto the roofing surface and usuallyintegrate well with conventional asphalt shingles. The company estimates that replacing a 450-square-foot section of conventional shingles with solar shingles can meet a third of a typicalhousehold’s annual electricity needs. Atlantis Energy System’s SunSlate PV tiles can beincorporated with tile, shake, metal or asphalt-composite roofs.Joe Schwartz, CEO of Home Power magazine, says one drawback to solar shingles can be themyriad connections and roof penetrations that the shingles necessitate. And the dark color andhigh absorbance of solar shingles can actually add to a home’s thermal load. (This can beremedied by insulating the home from the shingles, such as with a radiant barrier.)United Solar offers a simpler and less costly option with its PV laminates that are bonded directlyonto metal roofing. The photovoltaic sections are larger with fewer connections and roof-penetrating drill holes. These panels range in size from 4½ (31 watts) to 18 (136 watts) feet, withwiring either in the ridge cap or the eave soffit. On average, about 180 square feet of roof areawith good solar access generates 1 kilowatt of electricity. Go to for moreinformation.The biggest hurdle for installing PV-shingle or tile systems is their high initial cost. Uni-SolarModel SHR-17 solar roofing shingles, for instance, cost about $135 for every 7-by-1-foot section,not including installation, power inverter, batteries, mounting, fuses and wiring. You’re not onlybuying a roof, however, you’re also buying energy-producing solar panels.Additionally, a growing number of states now offer tax and rebate incentives of up to 50 percentof a system’s total cost to help ease the cost of investing in this renewable energy technology.(To find out if you are eligible for any incentive or rebate programs in your area, search theDatabase of State Energy Incentives at Factor this in with the reduced oreven nonexistent electricity bills you’ll encounter each year, plus the satisfaction of producingpollution-free electricity, and solar roofing becomes a far more viable roofing option.Roofing ResourcesFor a comprehensive listing of all green roofing materials and company information, we highlyrecommend Green Building Products, published by BuildingGreen ( SHINGLESSearch for Forest Stewardship Council- and SmartWood- certified products and TILE AND SLATEGladding McBean has more than 125 years of experience making clay roof tile and terra cotta.(800) 776-1133; www.gladdingmcbean.comTo find a clay-tile or slate roofing contractor or sources of new and used clay tile or slate in yourarea, visit the Directory of Slate Roof Contractors at www.jenkins
  11. 11. The Slate Roof Bible, by Joseph Jenkins, gives an in-depth look at slate roofing through the ages,and provides complete instructions for slate-roof installation and repair.RECYCLED ROOFING PRODUCTSPolymer-composites: EcoStar, (800) 211-7170; Euroslate: GEM, (403) 215-3333; Eco-Shake: Re-New Wood, (800) 420-7576; www.ecoshake.comPanelshake: Teel Global Resource Technologies, (800) 322-8335; www.teel-grt.comUsed tile and slate: Jenkins Slate, (866) 641-7141; & Co. Roof Thatchers, (845) 721-0443; www.thatching.comOffers consultation and installation services across the United States. Also sells ready-made,thatched-roof playhouses, doghouses and, for do-it-yourself projects, “shaggy” thatch by thesquare foot.LIVING ROOFSRoofscapes, (215) 247-8784; www.roofscapes.comWeston Solutions sells the GreenGrid system, which is a modular living roof design that allows forrapid installation. (312) 424-3319; www.greengridroofs.comVisit for the “international green roof industry’s resource and onlineinformation portal.” Go to or www.ecoroofs for generalinformation.Go to clean_rivers/ecoroof.htm to download detailed information onconstructing a living roof.Photovoltaic RoofingSunslate: Atlantis Energy Systems, (916) 438-2930; www.atlantisenergy.orgUni-Solar: United Solar Ovonic, www.uni-solar.comKeep Your Cool with Solar Attic FansMany homeowners install vents that rely on convection currents to help keep air circulatingthrough the attic, and others rely on active fans (powered by electricity) or windy days to keep airin motion. The best designs have continuous soffit and ridge vents to remove any moisture thatmight get into the ceiling or attic insulation. But if these vents are not feasible, solar-powered atticfans can be a reasonable alternative.During summer months, attics in many homes trap heat, putting an extra burden on your coolingsystem. In the wintertime, poorly ventilated attics can sequester warm, moist air that rises from ahome’s heated interior. As moisture condenses and collects on various surfaces, wood rot,
  12. 12. stained ceilings and peeling paint can result. If moisture infiltrates attic insulation, it can reducethe insulative abilities of the cellulose or fiberglass.A solar-powered fan (or vent) works solely on its own power, year-round, to help keep attic airmoving when you need it most — during daylight hours. No wiring is needed to install the fan, andmost are in place in less than 30 minutes. Some models can even be installed at the site of anexisting attic vent, eliminating extra roof penetrations. Because most are low-profile, theyintegrate almost seamlessly onto your rooftop. Solatube’s Solar Star attic fan circulates air at 800cubic feet per minute, providing coverage up to 1,200 square feet. Prices for solar-powered fansstart at $295.Natural Light Solar Attic Fan: Natural Light Energy Systems(800) 363-9865; www.solaratticfan.comSolar Star: Solatube(800) 966-7652; www.solatube.comElite Solar-Powered Attic Fan: EcoVantage Energy(877) 591-0661;
  13. 13. Recommended Books:Natural Remodeling for the Not-So-Green House: Bringing Your Home into Harmony withNature (Natural Home & Garden) (Paperback)by Carol VenoliaGreen Remodeling : Changing the World One Room at a Time by David JohnstonGreen Building Products: The Greenspec Guide to Residential Building Materials by AlexWilsonThe New Ecological Home: A Complete Guide to Green Building Options by Dan Chiras