Horizontal shot of a cool roof

Cool roofs offer protection from solar heat gain on hot summer days or all year round in warmer climates.

This innovative roofing reflects sunlight from a building instead of absorbing the heat and permeating the structure underneath. In the past, homeowners used white roofing to reflect the sun’s rays. 

But are cool roofs really that amazing? Well, they do come with their own set of drawbacks. This article will look at the disadvantages of a cool roof and why one may not be suitable.

Disadvantages of Cool Roofs

Let’s take a deeper look at the distinct disadvantages of a cool roof. 

High Installation Costs 

Replacing an existing roof with a cool roof requires a significant initial investment. Therefore, cool roofs might not be ideal for those operating on a tight budget.

As a homeowner, you can expect cool metal roof prices to lie anywhere between $5 to $14 per square foot, depending on the kind of cool metal roofing you install.

A steel metal roof is most common. On a home measuring 1,800 sq. ft (167.23 sq m), it would cost $35,516 on average.

High-end materials like copper roofing can cost nearly $48,000 to install.

However, keep in mind that the reduced maintenance costs and the energy savings that cool roofs offer can help offset this high initial price tag.

Lighter Roofing System Colors Might Look Dirtier Quicker

The lighter colors associated with certain cool roof products, especially a few of the light gray asphalt shingles, may develop algae streaks and get dirty quicker.

Workers retrofitting a home with a cool roof in the desert with spray foam polyurethane
Workers retrofitting a home with a cool roof

Certain asphalt shingles contain copper constituents to help postpone the growth of algae. Nevertheless, it will not ward off contamination and other natural deposits.

Increased Heating Costs 

Throughout winter, your home’s roof can use heat energy and sunlight from the sun.

A cool roof stops this from happening and may result in an increase in heating requirements during the colder months.

The exact extent is determined by the geographical location and variables of the winter season, such as snowfall, duration, and the number of warm and cloudy days. 

It can be that the case the extra heating energy needed because of the cool-roof effect during the colder months offsets the decrease in energy required to cool your home in the summer months.

Nevertheless, this might be true for certain climates but not all.

For example, if you look at it in terms of annual heating and cooling days, you can determine if you live in an environment with higher heating requirements than cooling needs.

In such a case, the benefits of a cool roof will not be that high.

May Not Be Suitable for Colder Climates

This point is linked to the earlier one.

The ability to absorb sunlight can be an advantage in particular situations.

In colder climates, solar gain can sometimes decrease heating costs during the winter season.

Nevertheless, in more northern climates where this could perhaps be the case, there are very few daylight hours during the winter, and the roof often may be covered with snow, which will block out the sunlight anyway.

In cooler areas, it’s a good idea to calculate the possible savings on cooling costs before applying a coating or membrane or installing a cool roof.

If you don’t need much air conditioning during the warmer months, a cool roof may not be a wise investment, mainly because it can increase heating costs during the winter.

Contribution to Global Warming

Like many other green products, the issue with cool roofs is that their environmental impact as a whole has to be evaluated when gauging their actual advantages.

A study looked at the net global warming for light-colored surfaces instead of their effect on a small area or a single building. The analysis revealed that white roofs contributed to global warming instead of reducing it.

This warming is because the surface of a cool roof sets off a chain reaction that increases the amount of sunlight received.

The white surfaces minimize the vertical movement of moisture into the atmosphere. This, in turn, reduces cloud coverage, resulting in reduced rain and an increase in drought-like conditions—the opposite result of the desired effect. 

The study concluded that more research needs to be conducted before these cool roofs can be deemed energy-efficient. 

Aesthetics and Design Limitations

Cool roofs have the following aesthetic and design limitations:

  • Limited color options: Cool roofs are designed to have high solar reflectance, which limits the available color options. The reflective properties are crucial for minimizing heat absorption, but this often results in a more restricted palette of colors.
  • Visual uniformity: The reflective surfaces of cool roofs, usually made of reflective coatings or materials like white membranes, may contribute to a visually uniform appearance. This uniformity might not suit all architectural styles or preferences.
  • Architectural compatibility: Cool roofs may not seamlessly integrate with certain architectural styles. For buildings with historic or unique designs that rely on specific roofing materials or color schemes, a cool roof might compromise the architectural integrity.
  • Maintenance challenges: Increased maintenance requirements to preserve the reflective properties and overall appearance. The need for regular cleaning may be an added consideration for those seeking roofing solutions with minimal upkeep.

Cool Roof Alternatives

If the disadvantages mentioned above make you think you don’t need or can’t afford a cool roof, here are some alternatives you can check out to keep your house cool. 

Ceiling Fans

Moving air can make you feel cooler.

By installing ceiling fans, you can create air movement that will help you cool down while avoiding the cost of AC.

A closeup of a dormant ceiling fan

During the summer, you can run your ceiling fan in a counterclockwise direction to draw the cooled air upward.

In addition, you can even switch on your exhaust fan, which will push out the warm air outside of your house.

Draw the Blinds

If you have windows that receive direct sunlight at any time of the day, you will benefit from keeping the curtains drawn or blinds closed for at least the hottest or sunniest part of the day.

For rooms on lower floors, you can turn your blinds upward to stop sunlight and heat from entering. 

Use Heat Reducing Film 

With almost 30 percent of ambient heat entering your home through the windows, one easy and quick fix to keep your house cool is to install a reflective, heat-minimizing window film to keep the temperature low.

What’s great about this film is that it also works in reverse and keeps more warm air inside during the colder months!

Insulate Your Attic Walls

Another great way to keep your house cool during the warmer months is to insulate your attic walls, which will reduce the amount of sunlight and heat flowing into your attic and stop it from escaping to the rest of your house. 

Use the Stove Sparingly

Using your oven or stove will add extra heat to your kitchen.

Try limiting your cooking to early morning and plan dinners that don’t need to be heated up, such as lettuce wraps or pasta salad. 

To prepare a hot meal without an oven, you can grill outside or use a crockpot. 

Switch Off Lights When Not in Use

Light bulbs produce heat, particularly incandescent ones. If you cannot replace these bulbs with a more efficient type, reduce their usage and turn them off when not in use. 

Open Windows at Night 

Take advantage of breezy summer evenings.

Open your windows at night to allow cross-ventilation that will help you and your family sleep better.

The cooler air is going to circulate all night. This way, you can start fresh with a cool house in the morning. 

Last Few Words

Like many other technological home innovations, cool roofs come with their own set of benefits and drawbacks.

In some cases, the disadvantages of a cool roof might be higher than the advantages it offers.

For instance, if you live in a colder region and don’t need much AC during summer, a cool roof might not be a good investment. In fact, it can end up increasing your heating costs during the winter season. 

If you don’t feel that a cool roof is suitable for you, choose one of the cool roof alternatives mentioned in this article.

Leave a Reply

Your email address will not be published. Required fields are marked *