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Happiness is “like a room without a roof,” in the words of that ubiquitous hit song, “Happy.”

Happiness is also a home with a good roof, especially in the oft-soggy Pacific Northwest.

Every homeowner wants a roof that looks attractive, doesn’t leak, lasts for many years and doesn’t cost too much. But in these days of climate change and waste consciousness, a roof should also meet high environmental standards.

Fortunately, plenty of green choices are available that can indeed make you happy about your roof.

Hot roofs

The environmental impact of a roof depends largely on the roofing material. For angled or pitched roofs, material choices include asphalt, wood, metal, clay, concrete, slate, plastic, rubber or a combination.

For a flat roof, the main choice is still the traditional “hot tar” created with asphalt and oil, although greener alternatives exist, such as planted vegetation roofs.

Before you decide on the material, consider what you want from your roof.

If you plan to install rooftop solar panels someday, you’ll need a type of roofing material that will accommodate — and hopefully outlast — them. Solar panels are commonly installed on standard asphalt shingle roofs, but metal roofs work even better.

Many Seattle-area residents collect rain runoff from their roofs in rain barrels or cisterns. If you use this water for the birds or for watering edible plants, avoid certain cedar shakes or other roofing materials that may leach chemicals, such as flame retardants.

Cool roofs

For a large roof surface that gets lots of direct sunlight, a “cool roof” may make sense in Western Washington.

Available in various materials, a cool roof is specially designed to reflect sunlight and keep your home cooler in the summer. The national nonprofit Cool Roof Rating Council provides details and product listings at

When planning a new roof, also ask: How green and durable are the underlayment and fastener systems? How will your new roof accommodate your gutter system or skylights?

If moss is a major worry because your roof gets heavy shade, will you be able to easily clean the roof without using toxic chemicals?

Choosing a roofing contractor you trust should help address many of your concerns. Get recommendations from friends, check online reviews or use a referral service.

Green roofs

Let’s take a quick tour of roofing-material options.

Asphalt shingles. The most widely used choice locally by far, asphalt shingles is also usually the cheapest option. Innovative new types are more durable, making them greener. Ask roofers if they can recycle your old asphalt-shingle roof, since contractors have recycling options in some areas.

Cedar shingles or shakes. Look for sustainably-harvested or salvaged-wood cedar roofing. Be leery of fire retardants and preservatives. Ask about durability and maintenance.

Metal. Though typically expensive, roofs made from steel or other metals have gained favor in the Northwest because of their moss resistance and durability. Most have impressive warranties. Metal roofs are eminently recyclable, and are often made partly from recycled metal.

Clay and concrete tiles. These can have a traditional or modern look. Like metal, they are durable but pricey.

Slate. An even higher-end option, a slate roof may last 100 years. Consider salvaged slate roofing, which is sometimes available at used-building-materials stores.

Plastic and rubber. Though usually considered less green because of chemicals they may contain, these options can be lightweight, durable and made from recycled materials.

Vegetative. Sometimes called green roofs, these usually feature plants in soil on top of a waterproof plastic layer. For a home, this works best on a small section of roof, or a garage or shed.

With all of our rain, we probably shouldn’t be surprised that the Northwest is becoming an epicenter of roofing expertise and choices. At least three roofing-material trade associations are based in Washington.

The roofing-materials industry has done an admirable job of providing eco-conscious choices. So let’s take them up on it, and make our next roof a greener one.

Tom Watson is project manager for King County’s Recycling and Environmental Services. Reach him at, 206-477-4481 or