When the topic of energy conservation and efficiency turns to commercial roofing, roof color sparks as much discussion as roof structure and type of insulation. The use of black versus white roofing materials received much attention after a 2014 study conducted by The Heat Island Group at Berkeley Lab examined the surfaces – including roofs and paved areas – that contribute to the summer “urban heat island” effect that’s felt in many metropolitan areas.
The study revealed that choosing white roofing materials could result in an overall energy savings of 9-36%.1 Dark surfaces such as pavements and roofs absorb sunlight, which adds warmth to the air. In fact, darker surfaces contribute to creating urban air that’s 1-3°C (2-5°F) warmer than nearby rural air.1 In contrast, on a sunny summer day, a flat white roof can reflect up to 80% of the incoming sunlight and can reduce air conditioning costs by 10-15%, depending on the region.1
Where roof color is concerned, location also matters. Research published in the Proceedings of the National Academy of Science in 2014 found that the Mid-Atlantic and Midwest see the biggest overall summer temperature increases and that white roofs could offset the heat island-induced temperature increases.2 The study also concluded that if utilized across an entire metropolitan area, white roofs could reduce some, though not all, greenhouse gas-related warming. Benefits of cool roofs are particularly prominent for the urban areas stretching from Washington, D.C. to New York, Chicago and Detroit, and California’s Central Valley.
The trend toward changing roofing materials to promote energy efficiency and reduce the urban heat island effect has had an impact across the country, with many cities and virtually all 50 states mandating some type of cool roofing, often offering tax rebates or other incentives to promote the use of these materials. Over the past several years, New York and Philadelphia have launched white roof projects, and other major cities are expected to follow suit.
1White Roofs May Partially Offset Summer Warming by 2100, February 2014; climatecentral.org
Whether you’re in need of a new roof, maintenance or repair for an existing roof, contact Jottan for expert advice and service – (800) 364-4234.
As our attention begins to turn to the rough winter months ahead, a team of researchers at Rice University is working on ways to solve the problem of ice-covered windows.
The team has developed a technology that uses a film made from graphene nanoribbons (pure carbon that’s one atom thick) covered with a thin layer of polyurethane to melt ice from windows. The film can be painted on any glass or plastic surface and conducts both heat and electricity. When voltage is applied, the film acts as a deicer while remaining transparent. It can even melt ice within minutes in a -4°F environment.
The research, published in Applied Materials and Interfaces, describes another key feature of the newly developed deicing film: radio frequency compatibility. While the film is transparent to the human eye, it’s also small enough (50 to 200 nanometers thick) to allow radio frequencies to pass through unimpeded. From windshields to commercial building windows, the technology could be useful to help diminish the harmful effects of ice without compromising access to cell phone and Wi-Fi signals.
Photo and information courtesy of buildings.com
As we move from the wonderful summer that we’ve enjoyed here in New Jersey with breathless anticipation of what lays ahead, our thoughts begin to turn from sun and sand to leaves, gutters, shingles and more.
Let’s start at the top! The best way to start preparing for those winter months is to have the roof inspected by a roof professional but should you decide to go it alone here’s a few tips.
- First and foremost, ensure that only trained personnel has access to the roof.
- Clear roof gutters of all debris and leaves. Why? Blocked drains are a leading cause of roof leaks and collapse. Gutters are designed to direct water away from the roof and building thus preventing pooling on the roof or by the bottom of the wall. When properly cared for gutters will do the job for which they were installed.
- Roof repairs. What may look like a small repair now could, when exacerbated by the bad weather, turn into a big repair costing more money and causing a dangerous situation. Remember, that while doing it yourself may be less expensive, in the long run a professional may be more cost-effective.
- Snow guards. Snow slides from a sloped roof can be a major cause of injury to you or others and also damage tiles as the snow slides down the roof. Snow guards will hold the snow in place as it collects on your roof until it melts and drains off into those free of debris and leaves roof gutters.
All of the above tips are easier and much safer to attend to prior to the beginning of winter. While leaves glistening in a gully of frozen water might present a nice wintery scene, the backup of water and snow under your roof won’t be quite as pretty. Nor will trying to find and repair a leak on a roof that is covered in snow.
Last but not least, always safety first.
Should you prefer to contact a professional to inspect and report on the condition of your roof for the upcoming winter, contact the company that’s been “Doing It Right the First Time for Over 30 Years” – Jottan – 800-364-4234.
Fall is such a beautiful time of the year. The summer heat is gone and the winter cold has yet to arrive. That time of the year when you no longer need the air conditioner and it’s not yet time to turn on the heat (love the savings!) How do you celebrate the arrival of Fall? Here are some fun suggestions for you, the kids and the family.
- Go apple picking
- Have your children help make their very own individual personal size apple pies
- Make homemade apple sauce
- Go for a family bike ride
- Wake up on a Saturday morning and just take time to enjoy the crispness in the air before starting your Saturday routine
- Sign up for your fantasy football league if you haven’t already done that
- Go pumpkin picking
- Bake a pumpkin pie and dry out the pumpkin seeds for a delicious snack
- Set up rotating football dinners among a small group of friends – each week a different person hosts the game and provides a light dinner or buffet
Roof slope is a very important aspect and it is considered the primary factor in roof design. The slope of a roof has an effect on the interior volume of a building, the drainage, the style, and the material used for covering and ultimately the cost. Below is a small summary of the advantages and disadvantages for both low slope and steep slope roofing systems.
LOW SLOPE & FLAT ROOF
Advantages: Require less material to build; less time to roll out and seal roofing materials than installing individual shingles; allows for easy maintenance since walking on a flat surface is easier; limits extra air and makes a structure easier to keep comfortable because a low slope roof limits this extra air and makes a structure easier to keep comfortable throughout the seasons.
Disadvantages: Changes how water flows off of the structure. On a roof with a lower pitch, standing water soaks between asphalt shingles and other overlapping materials. Shingles can’t be used on roofs with a slope below 8.5 degrees. Only rolled sheet roofing works on flat or very low sloped roofs.
STEEP SLOPE ROOF
Advantages: 50 percent longer lifespan than other roofing installation methods; faster water runoff, depending on pitch; lower chances of debris buildup, mold and mildew proliferation; can be covered with roofing materials that are fabricated and applied in small, overlapping units (shingles of wood, slate or artificial composition; tiles of fired clay or concrete; or even tightly wrapped bundles of reeds, leaves, or grasses.)
Disadvantages: Cannot cover a building of any horizontal dimension because it becomes too tall on a broad building.
For more information on Green Roofs, Low Slope and Steep Slope Roofs, contact the professionals at Jottan at 800-364-4234 or visit our website: www.jottan.com
A rooftop garden or a green roof can be as simple as containers and raised beds to roofs covered with soil and plants. While the terms are often used interchangeably there are differences which we explore below.
Green roofs can be as simple as a 2 inch covering of hardy groundcover or as complex as a fully accessible park complete with trees (not recommended for the traditional/conventional residential dwelling). While both green roofs and rooftop gardens provide environmental benefits, give sanctuary to animals and insects and do their part to improve air quality, a green roof is designed for maximum environmental benefits. By absorbing heat and acting as insulation, a green roof reduces energy needed to provide cooling and heating. While rooftop gardens provide shade and partial insulation, they will never provide the same benefits because rooftop gardens do not cover the entire roof of a building.
Other benefits of green roofs are: decrease in the production of associated pollution and greenhouse gas emissions by lowering air conditioning demand; and improving human health and comfort by reducing heat transfer through the building roof thus improving indoor comfort and lowering heat stress brought on by heat waves.
Green roofs focus on efficiency and lightness, while rooftop gardens are more aesthetic and created for their beauty or utilitarian purposes. Rooftop gardens can be created with the use of containers and raised beds and for far less than a green roof.
Though initially more expensive to install than conventional roofing, the financial benefits of a green roof are realized over the lifetime of the roof. The cover protection that a green roof provides means a longer life span compared to conventional roofing materials. Its natural insulation properties help buildings retain heat in the winter and protect the black tar from heating up in the summer thus reducing the energy needs for the building.
Regardless of whether you are installing a rooftop garden or a green roof there are certain issues to take into consideration.
- Care must be taken to ensure that the building is structurally sound and can hold the additional weight.
- Safety, for those on the roof and for those passing by on the ground. Ensure that equipment, containers and furniture are safely secured and that nothing is protruding upward from the floor of the roof.
Sources: www.epa.gov and voices.yahoo.com