Green Roofs

With energy costs continuing to rise, the popularity of green roofing systems is also on the rise. According to the US Dept of Energy, the average American household releases about 2 tons of carbon dioxide into the atmosphere as energy is consumed each year. It has also been reported that homeowners spend upwards of 11 billion dollars a year to cool their homes. California and several other states have passed tax incentives, rebate programs and building permit waivers for homeowners and businesses to help stimulate more eco-friendly and environmentally conservative building practices. Like many large cities, Los Angeles suffers from what is called the Urban Heat Island Syndrome (UHI). This problem is caused by modifying the land surfaces and displacing naturally occurring vegetation with heat absorbing materials like concrete and asphalt. Heat waste from automobiles, air conditioning units, and industrial energy uses all contribute to the Urban Heat Island effect. This results in irregular weather patterns like higher temperatures in summer months and loss of rainfall. Listed below are several types of roofing systems offered by Permanent Roof that can help to reduce the Urban Heat Island effect and the overall carbon footprint. Many of these systems are low maintenance, offer a substantial energy savings, and are a smart investment for homeowners and businesses. Los Angeles has recently published a study called the Green Roofs Resource Guide. Green roof systems are classified as: protective coatings, reflective membranes, garden systems, slate, metal, tile, concrete and photovoltaic. Scroll down for a detailed description and the benefits of each green roof system offered by Permanent Roof.

Reflective Roof Coatings

A reflective roof coating or white roof, is the best known and most applied of all Green Roof Systems. These systems reduce roof temperatures and thereby save electricity, and are great for almost every application, including residences, apartment buildings, condominiums, townhouses, retail buildings, schools, malls, and hi-rises.

White roof systems involve applying a fluid directly onto the roof. A superior acrylic roof coating waterproofing component and super tough polyester-mat as the reinforcement component is normally used. Compared to most re-roofing alternatives, this system provides an efficient, high-quality solution at a fraction of the cost.

Some of the benefits of white roof systems are:

• They are Safe to Apply: The roof coating is applied at ambient temperature, eliminating the possibility of injuries from 500 degree asphalt, and fires caused from overheated kettles or torches.
• There is NO adverse Environment Impact: Since there is no tear-off of the existing roof, and it is applied at ambient temperature, we are not contributing to landfill and not polluting the atmosphere with smoke. The reflective coating reduces roof surface temperature and saves electricity, the reason we call it a Green Roof System.
• They are Odorless: Acrylic roof coatings have NO odor, unlike the odors of melted asphalt or tar. Because there are no odors to irritate customers or employees, the project is less disruptive to your ongoing income producing business activity.
• Reflective coatings are Lightweight: The system’s light weight allows application over the original roof with a minimal weight increase: 40 lbs. per 100 sq. ft., as opposed to 175 lbs. per 100 sq. ft. for a cap sheet, and 500 lbs. per 100 sq. ft. for a gravel roof.
• And Strong: Over 300% stronger than fiberglass or organic roofing felts.
• And Flexibility: Acrylic roof coatings go on at ambient temperature and retain their structure and flexibility, unlike hot applications, which become brittle after drying.
• They Create a Monolithic Roof: As the polyester is embedded in the acrylic coating, the saturated membrane becomes a seamless, integral part of the total roof system.
• Reflective Coatings Keep the Building and Roof Cool: The white acrylic roof coating protects the roof from ultraviolet deterioration, and reflects solar induced heating from the building interior. This lowers the cost to run AC equipment and reduces energy consumption, maintenance, and utility costs.
• They are Cost Effective: This system can be expensed as maintenance, rather than capitalized over years like a conventional roof.

Los Angeles Times writer Margot Roosevelt, recently published an article in the Los Angeles Times talking about the benefits of White roofing and how it can reduce global warming. You can read her article entitled, To slow global warming, install white roofs here.

Garden Roofs

Used with great success in Europe, Canada, and Asia, garden roofs are beginning to catch on in the United States.

Garden roof systems come in two types:

Intensive- are built-in-place systems that are constructed on the rooftop. These systems use a deeper soil, which can accommodate larger plants, and even trees. These systems tend to cover the whole roof area with vegetation as opposed to the extensive or modular system, which employs the use of containers.

Modular Garden Roof System

Extensive- often called modular systems; they are assembled off-site and brought to the site ready for installation. These are self-contained biotic systems seeded with alpines, succulents, herbs, and grasses that are appropriate to the area. These systems are left alone to grow and develop naturally and are easier and quicker to install, while built-in-place systems require more maintenance and installation techniques.

Succulents have been proven to be the ideal plant for garden roof systems in that they have the ability to absorb water in their leaves, stems, and roots, which give them the ability to weather droughts and dormant times of the year.

Benefits from garden roofs include:

• Reducing heating and cooling costs
• Protects the roof membrane against UV radiation, temperature fluctuations, and punctures
• Extends the overall life of the roof
• Enhanced aesthetics of the building by recreating a natural habitat
• Absorbs carbon dioxide
• Produces oxygen
• Ability to absorb 50-95% of rainfall that falls on them
• Filters and controls storm water runoff
• Overall reduction of the Urban Heat Island Syndrome
• May qualify for green building certification credits

Garden Roofs are considered pervious building areas, allowing a developer to maximize the design of the building.

Photovoltaic (PV) Roof Systems

Photovoltaic (PV) roofing systems involve solar cells and panels that channel sunlight and convert it into electricity, thereby producing energy savings. California offers rebate programs for local businesses and residential homeowners interested in having PV systems installed on their roofs. Currently, the city of Santa Monica offers a building permit fee waiver for solar projects and an expedited permit process. Los Angeles Department of Water and Power offers solar incentives and is one of the largest programs of its kind in the nation. It has been estimated that California alone is the 3rd largest consumer of solar powered applications in the world. Another benefit to using a solar roof system is that they can collect and heat your hot water for even more cost savings over the lifetime of the roof. Used in conjunction with solar instead of electric attic fans, an attic’s temperature can be lowered by 50%, which can save a homeowner or business owner up to 30% on their air conditioning costs alone during the hottest times of the year. With these kinds of savings, it’s smart to consider a Photovoltaic Roof System. Right now, there are two main types of PV systems: amorphous and crystalline silicon systems. Amorphous systems are 9 percent efficient, with a flexible, thin film installed directly over the membrane. Crystalline systems are 34 percent efficient and are also installed over the membrane.

These systems have an average life expectancy of more than 30 years.

New PV technology called flexible thin film is also on the horizon. Nanosolar, a company in Palo Alto, makes solar panels from pliant sheets of foil, which can be molded onto roof shingles. More attractive, and costing less than traditional solar panels, experts say this product could produce electricity for about the national average of 10.4 cents per kilowatt-hour. While these roofs may cost more than a conventional roof, the significant savings over a 30-year period makes it well worth the money spent as this roof system will pay for itself in a very short time.

Metal Roofs

Metal roofs are often engineered with high quality recycled material, and can last as long, or longer, than any other roofing material. Currently metal roofs are manufactured with 60-65% recycled materials. The panels are also lighter than conventional roofing materials, which means less fuel costs during shipping. Average energy saving is significant, as the panels reflect 34% of the sun’s energy as opposed to conventional asphalt shingles. Metal roofs are also highly recommended for earthquake prone areas where heavier roofs can be a liability. They are also great for water catchments that provide irrigation for landscaping around a home or business. The metal panels can also be painted with reflective coatings for an even more energy conscious roofing system. Metal roofs are available in many styles and colors, including barrel vault, wood shake, and clay tile. Metal roofs can also have a reflective coating applied to them to save even more. Low maintenance, naturally fire, and pest resistant, a metal roof system is a smart choice for any home or business owner.
Berridge is one of Southern California’s premiere metal roof manufacturers.

Slate

The performance of slate as a roofing system is legendary – many roofs in Europe still function, even after 400 years! Slate is also one of the most environmentally friendly roofing materials available today. Slate is a naturally occurring substance, which can be laid out in a variety of patterns, is naturally fire and pest resistant, and often outlasts the underlying material that supports it.

For more information on slate, check out Traditional Roofing

Tile

Tile roof systems, like slate, have a long life span. New manufacturing methods and technologies have developed a tile that is both stronger and lighter than its predecessors. Tile is low maintenance, fire, and pest resistant and comes in a wide range of colors and styles. The tiles can be formed to mimic wood shake, conventional shingles, and other roof systems. When choosing tiles for your tile roof, you must consider such factors as climate, region, type of structure, desired aesthetics, new construction, or re-roof to find the most appropriate type for your project. Protect your investment: a tile roof is only as good as its installation.

Look for a contractor with tile roof installation experience. Evaluate life cycle costs when selecting a roofing product. Typical manufacturer warranties for tile roofs are 50 years or more, and tile roofs are not susceptible to fire, pests, or hail.

Concrete Tiles

Concrete tiles primarily consist of cement, sand, and pigments, and are available in an array of colors an styles, appropriate for any climate or architectural preference. Modern concrete tile designs can simulate the appearance of traditional clay tiles, wood shake, slate and stone. Manufacturers achieve these distinctive styles by altering various aspects of the tiles’ structure and placement. For example, like clay, concrete tile surfaces can be textured or smooth, tile edges can be uniform or ragged, and architects may select tiles of all one color, blended colors, or combine two or more shades and place them in a uniform or random pattern.

It’s Your Choice.

Permanent Roof will work closely with you to determine your needs, answer your questions, discuss your concerns, and help you decide on which green roofing system is best for you. Give us a call today at 310 838-ROOF or via email



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More Information

For more information on Green Roof Systems and other products, visit:
http://www.emagazine.com/view/?4191

http://www.greenroofs.org/

PV cells doubling as roof shingles:
http://ecologue.com/ShowArticle/Up-on-the-Roof

Cool roofs:
http://ecologue.com/ShowArticle/A-Cooler-Roof

To read more about the energy savings of Building-integrated PVs, see:
Energizing the Industry: Building-integrated PVs Take Commercial Metal Roofing to New Level of Sustainability