This book includes a plain text version that is designed for high accessibility. To use this version please follow this link.
THE INSIDE SCOOP
GREEN BUILDER RECOMMENDS
Begin with deciding what style of roof is appropriate to your home design. Then identify the most eco-friendly alternatives for that style. Keep in mind that some of the oldest roofing materials—clay tiles, slate, metal, or wood—may still be the best environmental choices, especially if the underlayment is extra durable. With shorter lived materials such as asphalt, go for “cool roofs” that will maximize life cycle and reduce home energy costs.


WOOD NATURAL, TO A POINT
Wood shingles and shakes (below) are the only roofing material that can claim to come from a renewable resource (trees), although it’s important to find out how and where that timber is harvested. A wood roof can easily last 50 years if installed and maintained properly. Wood shingles applied over a vented roof deck will remain cooler, dry out faster, and generally last longer.


Wood’s only serious drawback is its inherent flammability and susceptibility to moisture-related damage over the years. Because of these qualities, fire-and rot-resistant chemical coatings are often applied—and may need to be re-applied in later years. Most of these products have a potential negative impact on air and water quality.


VIRTUES
> Renewable
> Some natural rot resistance
> High natural insulating value
> 100% recyclable and biodegradable


CAVEATS
> High cost (materials and installation)
> Flammable
> Requires chemical treatment for fire safety and durability


 


CLAY/CONCRETE ALMOST FOREVER
Clay or concrete roof tiles (above) would appear to have it all: good looks, fire-resistance, and extreme durability. Recent innovations also address issues of stormwater management and enable cool roof capability. But the high cost of buying and installing masonry tile roofing has relegated its use to regional styles and high-end housing. Since 2004, its share of the residential roofing market has plummeted by more than half, to about 7%.


Nonetheless, a quality tile roof that is installed over a heavy-duty underlayment and screwed to the roof deck (not just mortared) should last for decades— if not a century or two—before it’s time to remove them, replace the underlayment, and put the tiles back on.


VIRTUES
> Durable
> Abundant resource and low embodied energy
> Natural insulating qualities
> Class A fire rating


CAVEATS
> High cost (materials and installation)
> Heavy
> Some types may be susceptible to freeze-thaw damage


 


SYNTHETIC OPTION
Majestic Slate synthetic roof shingles from EcoStar contain 80% post-industrial recycled rubber and plastic as a low-impact and lightweight alternative to natural slate. Small amounts of limestone fillers boost the tiles’ strength, durability, and resistance to UV damage. Several styles (including woodlook) and colors available. www.ecostar.carlisle.com.


INTEGRATED SOLAR
The SunTile series of high-efficiency photovoltaics from SunPower Corp. deliver a truly integrated array into most roofing styles and types. The S-shaped or flat tiles are designed to convert more solar gain into electricity, reducing the amount needed (and cost) to achieve a desired capacity and speed payback. www.sunpowercorp.com.


20
GreenBuilder 11.2010

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78