TRUSTED BY THOUSANDS OF DIY HOMEOWNERS
TRUSTED BY THOUSANDS OF DIY HOMEOWNERS
Concord Window Film customer Craig Clifford of New Jersey used an infrared thermometer to measure the temperature difference in his space after installing ComforTech™ 25 Ceramic Window Film — and recorded a 20-degree drop. He was impressed enough he's planning a second order to treat more windows on the back of his house.
At Concord Window Film, some of our favorite reviews aren’t reviews at all — they’re customers who send us proof.
Craig Clifford, a Concord customer in New Jersey, recently emailed our support team with exactly that kind of proof: side-by-side infrared thermometer readings from his own house, along with a short note about the results. We asked if we could share it, and he agreed.
Like a lot of our customers, Craig was skeptical that a thin layer of film could make a noticeable difference in how a room feels. His photos show a sun-exposed window with blinds, next to a seating area — a common trouble spot where direct solar heat gain makes a room uncomfortable during the sunniest parts of the day.
Last fall, Craig purchased our ComforTech™ 25 Ceramic Window Film — one of our most popular shades, offering strong heat rejection while balancing light. Indeed, ComforTech is right in the middle of our lineup.
It’s the same professional-grade ceramic film used by installers, available directly to DIY homeowners in easy-to-handle 2 mil precut kits. Unlike thin, sticky consumer films, ComforTech™ uses a dry adhesive and a thicker build that make it far more forgiving to work with during a DIY install.
A medium shade film that balances stronger solar control with visible light transmission. It is a superb all-around film offering performance in all benefit areas – including added daytime privacy.
Craig didn’t just tell us the room felt cooler — he tested it by measuring the temperature difference between a filmed window and an unflimed window. And the best part is after his experiment in June of this year, he was so pleased he emailed us about it.
In the photo below that Craig sent us, the window on the left is filmed with our ComforTech 25 Ceramic Series Film in shade 25. The window on the right is unflimed.
Then Craig measured the heat coming through each window by measuring the temperature of the couch in front of the window.
It’s important not to measure a window film’s performance by measuring the temperature of the glass. This is because window film works by reflecting some of the heat and absorbing some of the heat. The absorbed heat will make the glass itself feel hotter – this is by design. A feature not a bug as they say. You can read more about that in this article: Why Is My Glass Hotter with Window Film?
So the next photo shows Craig taking the temperature of the couch in front of the unfilmed window and he gets a reading of 113 degrees!
Next Craig measured the temperature of the same couch in front of the filmed window and he got a reading of 93 degrees!
After comparing and documenting the results, Craig shared this note with our team:
"Thank you for a wonderful product. I was pretty skeptical at first but I will certainly take a 20 degree difference. Now I have to order enough more so I can do the back of my house too. Just thought you should know. Thanks again."
And later when we reached out to Craig to ask if he would mind if we shared his experience with other customers, he said:
“It is always good for real world install people like me to actually see a difference. Admittedly, I was skeptical with it at first but it really does work.”
Craig’s order history backs up how he feels about the results: he placed his first order in September 2025, then came back in January 2026 to order more film — and noted that he has plans to extend coverage to the back of his house. A repeat order, in our experience, is one of the most honest reviews a product can get.
We are so grateful to Craig’s unsolicited feedback on our product – it’s one of the best parts of our job – hearing how our film is improving people’s comfort in their homes!
A double-digit surface temperature drop lines up with what we’d expect from ComforTech™ 25. Untreated clear glass blocks almost none of the sun’s energy — just 14% total solar energy rejection (TSER), with an SHGC of 0.84. ComforTech™ 25 rejects 69% of total solar energy and brings the SHGC down to 0.31, while still allowing 23% visible light transmission (VLT) so the room doesn’t feel dark. Even for double pane clear glass with an SHGC of 0.64, the film brings it down to 0.36. That’s a meaningful cut in the solar heat reaching the room behind it — exactly the kind of result Craig measured with his thermometer.
ComforTech™ film is also dual reflective, meaning it reflects heat more strongly on the exterior-facing side while keeping the interior side less reflective — so you get strong heat rejection without a mirror-like glare bouncing back into the room. You can view the full VLT, TSER, and SHGC specifications for every ComforTech™ shade in our performance specifications chart below:
For definitions of each of the specifications above, please see our Window Film Glossary.
If a sunny window is making a room in your home uncomfortable, Craig’s results are a good example of what a quality ceramic film can do. Browse our ComforTech™ Ceramic Series to find the right shade for your windows, or reach out to our team if you’d like help picking a VLT for your space.
Order a window film sample kit and see the film in your own space before you buy. This is the best way to determine which film and shade is right for you!
Our sample kit comes with 5″ x 7″ pieces of all five shades of our ComforTech Ceramic Series window film along with our Matte White Privacy and Silver 15 Reflective films. The kit costs $5 but comes with a coupon code for $5 off your first film purchase.
