How Hot Does Your Commercial Roof Get in the Summer?

Insights from Motor City Roofers in Detroit, Michigan
As temperatures rise during the summer months, so does the heat that radiates from commercial rooftops. For property managers and business owners in Detroit, Michigan, understanding how hot your commercial roof gets in the summer is critical for several reasons, including energy efficiency, building safety, and the longevity of the roof itself. At Motor City Roofers, we've seen firsthand how the summer heat can impact commercial roofs and what steps can be taken to mitigate these effects.

Why Your Roof Heats Up
First, let’s explore why commercial roofs get so hot in the summer. There are several factors at play:

1. Roofing Materials: The type of roofing material you have plays a significant role in how much heat your roof absorbs. Dark-colored materials like asphalt shingles or traditional built-up roofing (BUR) systems tend to absorb more heat compared to lighter-colored or reflective materials. Some roofing materials can reach temperatures as high as 160°F or more on a hot day.
2. Roof Design: Flat or low-sloped roofs, which are common in commercial buildings, tend to absorb more heat than steep-sloped roofs. This is because they have a larger surface area exposed to direct sunlight for extended periods.
3. Urban Heat Island Effect: In cities like Detroit, the urban heat island effect can cause temperatures to rise significantly. The concentration of buildings, roads, and other structures absorbs and retains heat, leading to higher ambient temperatures, which in turn increases the temperature of your roof.
4. Lack of Ventilation: Poor ventilation can trap heat within the roof structure, exacerbating the effects of external heat. Proper ventilation is crucial to allowing heat to escape and keeping the roof temperature under control.

How Hot Can Your Commercial Roof Get?
On a typical summer day in Detroit, where temperatures can reach into the 90s, the surface temperature of a commercial roof can easily exceed 150°F, depending on the factors mentioned earlier. In extreme cases, the temperature can even climb to over 200°F. This intense heat can have several consequences for your building:

1. Increased Energy Costs: When your roof absorbs a significant amount of heat, it transfers that heat into the building. This makes your HVAC systems work harder to maintain a comfortable indoor temperature, leading to higher energy bills.
2. Thermal Expansion: Extreme heat causes roofing materials to expand. Over time, this constant expansion and contraction can lead to cracks, splits, and other forms of damage that compromise the integrity of your roof.
3. Shortened Roof Lifespan: Excessive heat can accelerate the aging process of your roofing materials. Asphalt, for instance, can dry out and become brittle, leading to premature failure. Other materials, like single-ply membranes, can weaken and degrade under prolonged exposure to high temperatures.
4. Safety Concerns: In some cases, extremely hot roofs can pose safety risks. For example, roof-mounted equipment like HVAC units or solar panels can become dangerously hot, potentially causing burns or other injuries to maintenance personnel.

Mitigating the Heat: Solutions and Strategies
Understanding the heat your roof endures is only part of the equation. The next step is to implement strategies to mitigate the effects of this heat, ensuring that your roof remains in good condition and your energy costs are kept in check. Here are some solutions to consider:

1. Cool Roofing Systems: One of the most effective ways to combat roof heat is by installing a cool roof. Cool roofing systems are designed with reflective materials that minimize heat absorption and keep the surface temperature lower. Materials like white TPO (thermoplastic olefin) membranes or coatings with reflective pigments can reduce roof temperatures by up to 50°F, leading to significant energy savings and extended roof life.
2. Roof Coatings: Applying a reflective roof coating is another cost-effective solution. These coatings, which can be applied to existing roofs, create a reflective barrier that reduces heat absorption. Elastomeric coatings, for example, are popular for their ability to reflect sunlight and also provide a waterproof barrier, which adds an extra layer of protection to your roof.
3. Proper Insulation: Insulation doesn’t just keep heat inside during the winter; it also helps keep heat out during the summer. By improving your roof’s insulation, you can reduce the amount of heat that penetrates into the building, thereby lowering cooling costs and reducing the strain on your HVAC systems.
4. Ventilation: As mentioned earlier, proper ventilation is key to preventing heat buildup. Ensuring that your roof has adequate ventilation systems, such as ridge vents or turbine vents, allows hot air to escape, which can lower the roof temperature and reduce the risk of heat-related damage.
5. Green Roofs: A green roof, or a roof covered in vegetation, can be an excellent way to combat heat absorption. The plants absorb sunlight and provide natural insulation, keeping the roof cool. While green roofs require a significant initial investment, they offer long-term benefits in terms of energy savings, extended roof life, and environmental impact.

Monitoring and Maintenance
Regular monitoring and maintenance are essential to managing the heat on your commercial roof. At Motor City Roofers, we recommend scheduling routine roof inspections, particularly before and after the summer season. During these inspections, we check for signs of heat-related damage, such as blisters, cracks, or worn-out areas, and make necessary repairs.

Additionally, investing in a roof monitoring system can provide real-time data on your roof’s temperature and overall condition. This information allows you to take proactive measures before minor issues turn into major problems.

Taking Action Against the Summer Heat
The summer heat can be tough on commercial roofs, especially in urban areas like Detroit. However, by understanding how hot your roof gets and implementing strategies to mitigate the effects of heat, you can protect your investment, reduce energy costs, and ensure the longevity of your roofing system.

At Motor City Roofers, we specialize in helping Detroit businesses maintain and protect their commercial roofs. Whether you’re considering a cool roof installation, need repairs, or want to schedule a seasonal inspection, our team of experts is here to assist you. Don’t let the summer heat take a toll on your roof—take action today to ensure your commercial property stays cool, safe, and efficient.
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For more information on how we can help with your commercial roofing needs, contact Motor City Roofers in Detroit, Michigan. Let’s work together to keep your building and your business protected from the summer sun.