What is an SRI Rating?
SRI stands for Solar Reflectance Index.
The official definition from the U.S. Green Building Council is:
“A measure of the constructed surface’s ability to stay cool in the sun by reflecting solar radiation and emitting thermal radiation. It is defined such that a standard black surface (initial solar reflectance of 0.05, initial thermal emittance 0.90) has an initial SRI of 0 and a standard white surface (initial solar reflectance 0.80, initial thermal emittance 0.90) has an initial SRI of 100. To calculate the SRI for a given material, obtain its solar reflectance and thermal emittance via the Cool Roof Rating Council Standard (CRRC-1). SRI is calculated according to ASTM E 1980. Calcuation of the aged SRI is based on the aged tested values of solar reflectance and thermal emittance.” https://www.usgbc.org/glossary/term/5590“
Easy enough, right? Let’s put this simply – different colors reflect a different amount of light and heat from the sun. The SRI rating calculates the amount of reflectivity with the amount of heat being emitted and gives it a number so that you can easily compare colors. The higher the number, the more light the color will reflect and the more heat it will emit (or not absorb), allowing the roof to stay cooler.
CMG’s Bone White has an SRI rating of 81 while CMG’s Matte Black has an SRI rating of 25. The Bone White is going to reflect off more light and heat than the Matte Black. The Matte Black is going to absorb more light and heat than the Bone White. The Bone White is going to keep your house cooler than the Matte Black.
How important is an SRI rating when I pick out the color of my roof?
It’s great to understand what an SRI rating is, but now you want to know how important it is when making your color decision. The important thing to realize is that an SRI rating is calculated in a controlled environment. Your roof is not in a controlled environment.
Your roof gets different amounts of sunlight depending on the following factors:
- The pitch of your roof
- The direction your house is facing
- The amount of trees or obstructions around your house
- The climate of where you live
All of these things will affect the amount of sun your roof will see.
If you live where the temperature is hot with lots of sunshine all year long, a higher SRI rating could make a substantial difference in your cooling bill because your roof is reflecting away more light and heat. If you live where you have cooler temperatures, than an SRI rating might be less of a factor because you will have times when you want to heat your house, not cool it off.
I like a specific color but I want it to have a higher SRI rating. Can you do that?
No, we cannot change the SRI rating of color. The color itself is a determining factor in how much light and heat it will reflect. We cannot change how much light and heat a color will reflect or absorb so we cannot change the SRI rating. The Matte Black will always absorb more light and heat than the Bone White. It is not possible to alter a dark color to have the same SRI rating as a light color.
What color roof would look good on my house?
This is a bit of a loaded question for a number of reasons. The first being, we have never seen your house. Even with a very detailed description of the house, the siding, the trim, etc., it is very difficult to imagine what all of that looks like together.
The second reason is you and the person on the phone could have VERY different tastes. You may love the look of the Copper Penny while the CMG employee could tell you that Copper Penny is not her favorite color. We would hate for you to pick a color based on our personal preference and then not love it. Remember, this is the roof you are going to have for the next 30+ years. The most important person to love the color is you.
We would love to send you a sample chip so that you can see the actual metal in person. Your contractor may have metal sample chips to show you as well.
The sample chip will give you a much better idea of how the metal will look on your house.
- Hold it next your siding.
- Hold it next to your trim.
- Look at it in the sunlight.
- Look at it in the shadows.
- Look at it in the morning.
- Look at it in the evening.
Color will look different in different lighting. You may love the Medium Bronze when you see it in the sunlight but may notice it has a bit of a green undertone when it is in the shadows. You may love the Weathered Zinc in the afternoon but not care for the metallic sparkle when it catches the morning sunlight.
We know color selection is an important decision and highly recommend seeing a sample of the color you are considering.
What color is most popular?
You would think this question would be easy to answer: Do the math, add up the colors we sell, and see which ones has the most sales. We can make it that simple if you want, but don’t depend on this solely to pick your roof.
We can’t tell you what color is most popular on a log cabin style house, or a midcentury modern ranch, or a traditional two story home. We can’t tell you what color is most popular on Nashville homes or Phoenix homes. We can’t tell you what color is most popular on white house or gray houses or red houses.
Another thing to keep in mind is that color trends change. Currently, grays and blacks seem to be very popular. Five years ago, brown and tans were more popular. Before that, greens were popular. Color trends change but your roof lasts a life time.
To look for color inspiration check out the following:
These options may help you better visualize what your house could look like with a new roof.
I’ve looked through your color chart and don’t see the color I want. Can I create my own color for my roof?
CMG can do custom colors upon request but there are a few requirements:
- There is a minimum quantity amount based on the substrate, gauge, paint type and width. This could be anywhere from 5,000lbs to 40,000lbs. Most residential jobs are substantially smaller than this, meaning you would end up with a LOT of extra material after the job is over.
- Based on the same factors of substrate, gauge, paint type and width, along with the quantity ordered, custom orders can be substantially more expensive than a standard CMG color.
- Custom orders require a long lead time. Estimated lead times on custom colors can be 8 to 12 weeks.
- You will be required to provide us with a physical sample to color match. We are unable to process custom orders based off a color name, number, or description.
How much is my metal roof going to cost?
There are number of factors that go into the cost of purchasing and installing a metal roof, so unfortunately, we do not know what a contractor would charge you.
Your contractor has more than the just the cost of the steel to factor into the price of the metal roof. If the steel is shipped to them, they have the freight costs to factor in.
Your roof may have many peaks and valley and require extra trim work which turns into extra material and extra labor for your contractor.
Your roof could be three stories high and require a lift or scaffolding which is an extra cost for your contractor.
There are simply too many factors to take into consideration when pricing out a roof for us to take a wild guess for you. Getting an estimate through a contractor is going to be the best way to get an accurate cost of purchasing and installing your metal roof.