For business owners and homeowners looking for ways to save on their energy bills, solar reflective paint on the roof offers a simple, yet powerful method of reducing air conditioning costs.
The principle of solar reflective paint is simple – it reflects the heat and sun rays.
The white color of the heat reflective paint reflects the solar rays that otherwise would hit the roof and cause the interior temperature of the building to rise.
By reflecting the rays, the heat is reflected as well which means that your air conditioning unit will run less often.
Because the paint works on different types of surface materials, it can be applied to most roofs.
Plus, there are no special requirements for applying these heat-blocking paints.
If the roof of your building has a dark color, heat reflective paint can be applied with ease. You can apply it the same way as standard paints without using special equipment.
What are the Benefits of Heat Reflective Roof Paint?
The benefits of solar reflective paint (also called heat-reflective paint or anti-glare paint) start with the passive quality of the paint to reflect heat.
In other words, once applied, the paint works to reflect the solar rays when the sun is out.
The paint does not need any additional support or energy to do its work.
This means that once you pay for the paint and its application, you do not pay anything else until the paint needs to be replaced.
1- It’s Highly Versatile:
The solar paint can be applied to different surfaces that include metal, concrete, brick and mortar, bitumen, stable felt, and more.
Because of the wide range of materials, anti-heat paint can be used on different types of roofs, including conservatory ones.
It can also be used for walls that face the sun most of the day to reflect solar heat as well.
2- Good for old roofs:
If you are planning to repair old asphalt roofing rather than setting out the new one, solar paint and heat reflective coating can be a fantastic option.
The most reliable paints on the market meet the requirements for the Energy Star reflectance performance requirements.
Plus, they provide protection to various types of roofs like pitched roofs, and flat roofs, along with low and high-sloped metal roofs by providing over 80% of the sun’s rays.
3- Fungal Growth Reduction:
For humid areas that suffer from fungus, the paint has qualities that reduce fungal growth.
This means a reduction in the need to treat surfaces for fungal growth that have this paint applied.
However, there are a few issues with heat-blocking paint, which you may need to keep in mind before applying them.
What are the Cons?
The first major drawback is that solar reflective paint is somewhat more expensive compared to standard paints.
Although the price difference is not too great, it should be noted that ordinary white paint may not have the durability to last on the roof compared to the heat-resistant type.
Another issue is that at best, heat-reflective roofing paint will reduce energy costs by up to 15%.
While 15% is nothing to sneeze at, it’s also not all that dramatic of a decrease.
There are reasons why the paint does not do a more efficient job, but keep in mind that the sun is only one of several reasons why your home may be heating up.
And finally, if you live in an area that gets cold during the winter, then the heat reflective paint may work against the snow melting off the roof.
The added weight of the snow over time may cause damage to flat roofs at a higher rate compared to dark paint which helps melt the snow.
It is why some advocate for solar air conditioning rather than heat reflective paint as being a better, all-around choice.
Solar Air Conditioning vs. Heat Reflective Paint: What’s Better?
Solar air conditioning is the use of solar panels to run your air conditioning system.
The benefit is two-fold as the solar panels on the roof either absorb or keep the sunlight from striking the roof.
And the power generated by the solar panels runs the air conditioning which saves on your electricity bills.
For comparative purposes, the solar air conditioning system offers considerable advantages over heat reflective paint.
The most important of which is that it generates electricity which means that you save more on your energy bills by comparison.
Plus, the solar panels will reflect much of the light that strikes the roof, although not quite as much as the heat reflective paint.
Where the paint has the advantage is that solar panels require maintenance and care, which adds to the overall cost which is considerably higher.
While the solar panels will pay for themselves eventually, the initial cost along with the maintenance is higher compared to the heat shield paint.
Which works better?
In terms of which one is better, solar air conditioning has the advantage over paint that repels sunlight.
It works well across the country no matter the temperature conditions in providing electricity to the building.
While the panels will require maintenance, the cost is normally paid for long before the panels stop working.
This means that despite a higher initial investment, solar panels will pay for themselves and keep adding value for many years to come.
However, if you are on a strict budget and solar panels are not a practical addition to your building, then heat and light reflective paint is the better choice.
Heat reflective house paints do not do as well during the winter months, but you can save upwards of 15% on your electricity bills.
A Few Other Ways to Cool Down Your Roof and Control Heat Absorption
Roofs, particularly polycarbonate roofs in your conservatory, can be very hard to keep cool in extreme summer temperatures.
And that’s the reason, metal, slate, single-ply membrane, clay, terra cotta or rubber shingles are the better options for homeowners in warm climates.
But if you already have your roofs installed and want to control heat from the roof, there are a few widely accepted ways and expert tips out there – besides using sun reflective paint for the roof.
Some of them include:
1- Tiled roof
Tiled roofs for the conservatory not only enhance the aesthetics of your property but also help by improving thermal performance by making a significant difference to the temperature.
If you like to keep your roof look more traditional without giving them a feel of glazing, tiles can be a great option for homeowners living in areas with warm climates.
2- Glass roof
Unlike old polycarbonate, glass does not overheat your roof much.
So, to boost the thermal performance and keep the temperature under control you can definitely go for a glass roof replacement for your conservatory which should be within your budget.
3- Integral blinds
If you already have glass panes installed on your conservatory’s windows and glass roof, integral blinds can be installed.
These are available in a wide range of colors and you can opt for manually or electronically operated options to keep your place cool as well as shaded.
4- Window film/tinting
Metallic coating/films and tinted windows are the other great options that can be added for keeping your place naturally cool via an overheated roof.
These are almost invisible and can help in reflecting the sun’s rays to reduce the solar glare and heat to a significant level.
5- Go green with a rooftop garden
Roofs other than conservatories can be replaced with rooftop gardens to reduce the surface temperature as well as overall building temperature.
Plus, it offers a great many benefits along with a feeling of pleasure to homeowners who love gardening but do not have a backyard garden available.
What color paint does reflect heat best?
For keeping your house exteriors cool, white paint color is the most effective and popular choice among the masses.
Additionally, you can use ultra-white cooling paint for roofing which will
reflect light and heat from the UV sun rays.
Silver paint color also reflects heat like white and is also many times preferred by homeowners who have excessive cooling costs during warmer seasons.
When choosing the UV reflective paints and the colors, keep in mind that these paints are only effective in reflecting or rejecting the heat energy from the sun.
It provides no energy benefits if you apply them to the inside of a building.
So, they should only be used on exteriors and roofing.
How much does heat reflective paint generally cost?
Heat reflective paint arent cheap and is therefore not widely used as a preferred coating for all types of houses and roofs.
On average, you can expect to pay around $13 to $15 per square meter (or per 10.5 square feet) for coating a normal house roof with solar heat-reflective paint.
Depending on the brand of paint and your roof condition, this estimation can go even higher.
What are TSR and SRI – How do they relate to roof coatings?
Total Solar Reflectance (TSR) simply refers to the method that measures the reflective capability of a surface coating.
It is generally represented as a percentage between 0% and 100%. The higher the number, the more effective is the surface at reflecting the radiation from the sun back into the atmosphere.
This also means that surfaces with a higher TSR will tend to stay cooler than the surface with coatings that absorb more heat and sunlight.
Then there is another term used which is Infrared Emittance (E). Its also referred to as Thermal Emittance and is rated between 0 and 1.
It refers to the ability of a surface to get cooled by releasing the heat back into the environment.
Solar Reflective Index (SRI) is yet another term used in roof coatings, which is a combination of TSR and E values (TSR x E). It’s rated from 0 to 100 where 0 is generally for black surfaces and 100 for standard white.
SRI is most commonly used by paint/coating manufacturers to measure the reflectivity of the surface. This helps in picking the highly reflective roof coating product to save you money on your cooling bills.
The Bottom Line
As you can see, solar reflective roof paint and coatings can be one of the best ways to keep the temperature under control.
These reflective roof coating and protection paints are also available in color options like white, black, and a few others.
But it isn’t the only way you can choose for your property.
If you think it’s a lot of hassle to pick and apply the right heat reflective paint, you can go with many other ways to cool down your roof I have mentioned above.
It all comes down to your expectations, the condition of your roof, the color, and the budget you have in mind.
Jack Luis is a semi-retired painter who loved painting his clients’ ideas on their walls.
He had worked as a painter for over a decade serving customers in areas such as Charleston, Mount Pleasant, Beaufort, and Georgetown, SC (South Carolina). Today in his free time, he likes to read and write about the newer techniques implemented in his profession. You may read more about him here or get in touch with him here.