According to a 2015 survey, nearly 75% of Millennials are willing to pay more for sustainable products and 45% of all consumers say the impact on the environment can sway their purchases. This explains why every product, from drinking straws to roofing materials, is being considered and chosen with the environment in mind.
In the past, homeowners might have viewed the role of the roof as passive. It sat there looking nice and creating an attic space where insulation could do its job, and they thought no more about it. Now, however, roofing companies and homeowners alike are considering the role the roof itself can play in the energy efficiency and sustainability of a home. Here are three environmental (and practical) considerations to keep in mind when choosing roofing materials for your Northern Virginia roof replacement.
Heating
During winter, the roof can play a major role in keeping a house warm. Hot air tends to rise and heat flows from warm spaces to cold spaces. Therefore, the attic space of your home is key to keeping your house warm in the winter. The cooler the attic space is, the more heat will be drawn upward and lost from your living spaces. Heavy materials, such as shingles and roofing tiles, are good insulators. That is, less heat escapes through heavy roofing materials because it takes more heat to warm heavy materials than it takes to warm lightweight materials.
The type of materials used when replacing your roof can also have an impact. Materials like slate tiles, rubber tiles and asphalt shingles have low thermal conductivity. This means heat does not pass through these materials easily, staying inside the attic during the winter rather than being transmitted to the exterior air. While metal roofs would intuitively seem like they would not protect against cold, they have been proven to keep houses warmer than asphalt shingles during the winter. During winter, metal roofs and asphalt shingles absorb heat during the day when the sun shines on the roof. However, as one study conducted by the U.S. Department of Energy found: while asphalt shingles gain more heat during the day, they lose more heat at night when compared to metal roofs. At night, asphalt shingles keep the heat in the roof. Metal roofs retain more heat at night as the temperature in the attic from the radiated heat was up to 20 degrees warmer. Metal roofs also allow snow and ice to slide off the roof more easily, thereby reducing heat loss (and thus energy loss) to melting ice and flowing water.
Cooling
During the summer, roofs need to perform the opposite function by keeping excess heat outside of your home. Hot air trapped in the attic tends to inhibit cooling of the house. Aside from giving hot air no place to naturally rise, air conditioning ducts are often located in the attic and hot air in the attic will reduce the efficiency of the air conditioning system.
Thermal insulators are considered by roofers to be a good choice for summer cooling when replacing your roof. These materials are widely available from roofing contractors and include concrete tiles, slate tiles, rubber tiles and plastic tiles. As might be expected, light colors reflect more summer heat and sunlight than dark colors, which tend to absorb and hold heat and energy from the sun. Moreover, roofing materials may be pre-treated with reflective coatings to further reduce their heat absorption.
Again, metal roofs present counter-intuitive benefits for summer cooling. While you may expect metal to heat up easily and create a virtual oven, the opposite is actually true. Metal is highly reflective and tends to absorb little of the light and heat from the sun. This means that a metal roof tends to remain fairly close to the exterior air temperature, rather than heating up like some other roofing materials.
Sustainable Materials
Replacing your roof can require plenty of materials. Fortunately, many roofing materials are considered eco-friendly. Metal roofs are durable – with minimal maintenance they can last over 30 years and fewer replacements mean less waste. Moreover, when replaced, metal roofs are fully recyclable.
Synthetic slate tiles, rubber tiles and recycled shingles are made from recycled plastic, rubber and wood fiber. Slate tiles reclaimed from old buildings have character and require no stone to be cut to produce them. With few or no new inputs, these roofing materials are sustainable.
By carefully selecting your roofing materials, a residential roof replacement presents an opportunity to improve the energy efficiency and eco-friendliness of your home.