Using various strategies, like reflecting or capturing light, energy-efficient roofs help reduce global greenhouse gas emissions by decreasing the electricity needed to cool your home. With three options for energy-efficient roofing systems available, homeowners on any budget can access the energy reduction and savings they provide.
In this article, I’ll use my roofing expertise to shed light on the ins and outs of energy-efficient roofing systems. Specifically, I’ll discuss their costs, maintenance, and installation needs to aid you in determining which is right for your needs.
If you’re in the market for a new roof (maybe even an energy-efficient one), consider my recommended roofing professionals to begin the installation process:
- Cool roofs, green roofs, and solar roofs are energy-efficient roofing systems.
- Energy-efficient roofing systems can save you money on your home energy bill and make your house more environmentally friendly.
- Utility companies and government programs offer rebates and incentives to homeowners who choose energy-efficient roofs.
- Energy-efficient roofs can be installed on almost any type of home.
What Are the Different Types of Energy-Efficient Roofs?
There are three primary types of energy-efficient roofs:
- Cool roofs
- Green roofs
- Solar roofs
They work by reducing solar reflectance and the absorption of solar radiation, increasing the insulative value of the house, and redirecting solar energy to generate electricity or sustain plants. I’ll look at each in more detail in the sections below and outline their strengths and weaknesses.
Cool Roofs
A “cool roof” is a system of strategies to increase the roof’s ability to reflect ultraviolet (UV) sunlight, the biggest culprit in heating up a roof. UV light can heat shingles to 150℉, and much of that heat gets absorbed into the house. Reducing the amount of UV light that heats up the roofing material results in a cooler home and less energy needed for air conditioning, especially during hot summers. Energy-efficient roofing material is key to a cool roof system.
There are two ways to increase the reflectivity of roofing materials and achieve a cool roof. First, choose a light-colored roofing material if you’re putting on a new roof. Terra-cotta, for example, is naturally light-colored, meaning more light gets reflected. A white roof is the best choice, but if white is too bold for some, any light-colored roofing material is advantageous.
Second, it’s not strictly required to have (or choose) a light-colored roofing material. Any roofing material — metal roofing, asphalt shingles, tile roofing — can be coated with a reflective silicone coating (sometimes called a cool roof coating) that achieves the same effect as a light-colored roofing material.
It doesn’t matter the type of roof or the age of the roof either. Reflective coating can be applied to old shingles (though if they’re nearing the end of their service life, it makes sense to hold off for a roof replacement.)
Reflective coating can even help extend the health of the roofing material (especially asphalt shingles) by reducing the heat-based expansion and contraction that roofing material undergoes throughout the day and seasons. (Some profess to help prevent or seal leaks, but I would be skeptical of those claims.) The biggest selling point of reflective coating is that it’s the least costly and easiest option. For a few buckets of coating and just a couple hours of work, your roof could be up to 50 degrees cooler on a hot day.
The drawback to a cool roof is that other systems do what a cool roof does but provide additional benefits. While it’s great for those on a tight budget, other energy-efficient roofing options might be preferable for homeowners with a roomier budget.
Read also: Overview of 3-tab vs architectural shingles
Green Roofs
A green roof (sometimes called a “vegetative” or “living” roof) is a garden on a roof. Upon closer examination, what appears a bit silly at first is a clever and environmentally friendly system to increase energy efficiency and promote healthier housing methods.
The roof installation is conceptually straightforward. A waterproof membrane is laid over the roof. On top of that, a thin layer of drainage material is applied to take away excess water. Lastly, the growing medium and plants are added.
There are two types of green roofs: extensive and intensive. Intensive requires regular maintenance and upkeep, though these are rarely used on homes. Instead, extensive types are the most frequently used for housing, as they require very little maintenance — often nothing more than weeding once or twice a year.
Green roofs have a variety of benefits. The thick layer of plants and organic matter shields the roof from direct sunlight, thus reducing the roof’s temperature during summer. In winter, it acts as an insulation layer that helps keep heat inside the house. For those concerned about the environment, green roofs capture stormwater and prevent it from becoming run-off in streets and storm sewers, where it picks up pollutants and gets dumped into nearby rivers and streams.
For all the benefits, though, it does have disadvantages. Constructing a living roof can be a substantial project. It requires a waterproof membrane, drainage system, growing medium, and structures to retain everything and keep it on the roof. Also, not all roofs can accommodate a green roof. Roofs that are too steep need to be fully reconstructed to accommodate a green roof, or a different energy-efficient option needs to be employed. Maintenance can be an issue too. While the extensive type of green roof needs little maintenance, it needs maintenance nonetheless. In a busy, modern world, many people are trying to reduce the time and labor needed to keep up with everything, not increase it.
Solar Roofs
Solar roofs are fast becoming the prevailing energy-efficient choice for homeowners. Advancements in consumer-grade solar technology have made rooftop solar panels a viable option for many homeowners.
Solar roofs use photovoltaic (PV) panels arrayed on the roof to capture sunlight and turn it into electricity. They’re added as a complement to a standard roof, meaning no major reconstruction or reworking is required to install a panel array. The panels output electricity directly to the house or can be installed in conjunction with a bank of batteries that store the electricity for use at night or during cloudy weather. To be clear, batteries aren’t necessary for solar roofs; they’re only an option.
A compelling argument for solar panels is the variety of programs, credits, and rebates offered by federal and state governments and some utility companies. For example, the federal government offers a tax credit of 30% on the entire cost of installing solar panels on your home. Considering the up-front cost of solar panel installation, that’s not insignificant savings for many of us.
There are options to avoid up-front costs, too. A crop of companies has sprouted across the U.S. that offer “no-money-down” installations. That doesn’t mean it’s free, but it does mean that homeowners can defer costs at the outset and structure them into a payment or reimbursement plan.
If you’re curious about how solar power works, check out the video below from the National Renewable Energy Laboratory (NREL):
How Much Do Energy-Efficient Roofs Cost?
The cost of energy-efficient roofs varies according to factors influencing the installation (labor) costs and the material and equipment costs. Steep roofs, large roofs, and complex roofs will all increase installation costs. Different grades of equipment will result in higher equipment costs.
| Type | Average Cost for 1,500 Square Feet |
| Cool Roofs | $6,500–$10,000 |
| Green Roofs | $10,000–$20,000 |
| Solar Roofs | $5,400–$18,000 |
While costs can look intimidating, they don’t tell the whole story. The goal of an energy-efficient roof is to reduce your energy costs. If you look at a roof as an investment and see savings as a return on that investment, you see that over the life span of the roof, the investment pays off in the end.
A green roof might be $20,000, but it has a service life of 60 years. Most houses will have had at least two roofs put on in that time span. So not only do you save on 60 years of utility bills, but you also save on the bill for two new, conventional roofs.
Read our guide on the latest trends in energy-efficiency home upgrades.
How To Choose the Right Energy-Efficient Roof for You
There are some factors to consider in choosing an energy-efficient roof. I’ll go over each and their pros and cons.
Cool Roofs
A cool roof is great for a homeowner on a budget. Light-colored roofing materials aren’t much different than the same type of material with darker colors. If you’re not replacing a roof, then reflective coating is low-cost with minimal labor. It’s also great for homes with difficult or complex roofs that are not easily converted to a green roof or solar roof. While a steep or complex roof might increase the cost of a cool roof, it’ll still be much cheaper than the alternatives.
For homeowners in cold climates with short or light summers, a cool roof might not be worth the cost — even if it’s minimal. But for homeowners in hot climates, the energy savings are well worth the cost.
Reflective coating can be applied to already existing roofs of any age or material type.
Green Roofs
Green roofs are best suited for homeowners who want to help the environment and save on their energy bills. They’re also particularly attractive for cooler climates where their insulative value can help keep a house warm in the winter. Because green roofs are populated with native plants that have evolved to survive in the local climate, they’re viable everywhere, from hot and dry areas to cold and snowy ones. Virtually anywhere that plant life exists, a green roof is a possible solution to energy efficiency.
Solar Roofs
Solar roofs are best for all-around utility. Not only do they shade a roof and achieve the cooling effect of a cool roof, but they provide electricity that can drastically reduce a homeowner’s energy bill. Excess electricity is sold back to the electric company, and the solar roof will profit the homeowner in the form of reduced energy bills.
Related: Castagra Roofing Review
Certain roofing contractors and solar panel installers work together to do dual installation of the roof and solar panels. This makes the process quicker and more efficient and provides cost savings to the customer.
DIY Vs. Professional Installation of an Energy-Efficient Roof
A professional should install an energy-efficient roofing system. Silicone reduces the coefficient of friction, making a roof slippery. Solar panels require soldering, transformers, and electrical work to tie into the house’s wiring and the electrical grid. Green roofs require an expert who understands the roof’s structural limits, the appropriate growing medium, and what plants are best suited to the location.
If you’re unsure about how to choose the best option for your roofing service, we recommend reading our article on tips for finding professional roofers.
Because energy-efficient roofs can be complex and require technical knowledge, a professional will ensure that all materials and equipment are correctly installed and meet the requirements of any manufacturing and installation warranties. Improper installation or workmanship can be used as cause by a manufacturer or company to void any warranty on their product.
How To Maintain an Energy-Efficient Roof
Each type of energy-efficient roof has its own needs and requirements. None of them require substantial or intensive maintenance, but all require some maintenance.
Cool roofs are maintained the same as conventional roofs. They require regular visual inspections, basic clearing of debris, occasional moss and lichen removal, and general cleaning of dirt or other matter as needed. Be careful if you have silicone coating on your roofing material. It’s slippery, and if a roof is generally dangerous, it’s doubly dangerous with a silicone coating. I recommend against accessing your roof. Do the best you can from the ground or ladder.
A green roof is a living thing, no different than a flower garden. And like a flower garden, it needs some degree of regular care. Extensive-type green roofs are the preferred choice for minimal maintenance, but that still means a few rounds of maintenance a year. This includes basic weeding and removal of plants growing in places they shouldn’t. In periods of drought, the roof will likely need watering. In some cases, it will need to be fertilized.
Solar roofs are low maintenance. General cleaning once or twice a year is sufficient. It doesn’t require involved cleaning, either. Remove debris and keep it clear of anything that might prevent light from entering the panel, and it’ll be good until it needs to be replaced.
Explore our comprehensive guide to roof inspection for valuable insights into maintaining the integrity of your roofing system.
So, Is an Energy-Efficient Roof Worth It for Your Home?
Absolutely. Energy-efficient roofs offer a variety of benefits over traditional roofing that are appealing to most homeowners. They lower household energy consumption, provide electricity, and even beautify the home. While cost can be a factor, if you can afford the up-front investment, it’ll pay for itself (and more) in the long run.
FAQs About Energy-Efficient Roofs
Are there energy-efficient roof shingles?
Yes, shingles with lighter colors have increased thermal emittance, which translates into better energy efficiency. Light-colored shingles reflect more UV light than dark-colored shingles, meaning your roof (and, therefore, house) stays cooler.
What is a “cool roof”?
A “cool roof” is a system of materials and techniques used to help a roof reflect as much UV light as possible, which assists in keeping the entire house cooler.
Why do roofing companies make roofing materials energy-efficient?
Roofing companies fulfill the demands of the market. Homeowners desire roofs and roofing materials that are energy-efficient, and roofing companies do their best to fulfill that demand.
