Year-round comfort
ThermaCore Low-E: for summer heat and winter chill
ThermaCore Low-E is a low-emissivity film that helps cut heat gain in summer and helps retain warmth in winter. It is a film for the glass you already have, not a replacement for new low-E windows.
In stock
- Helps limit heat loss in winter
- Useful where nights get cold
- Little change to how the glass looks
- Keeps rooms feeling bright
- Applied in a vacuum chamber
- Controls radiant heat, not just light
What “low-E” means
Emissivity is how readily a surface gives off heat. A low-emissivity (low-E) layer gives off less, so it helps keep heat on the side where it started: indoor warmth stays in during winter, and outdoor heat has a harder time passing through in summer.
Newer windows often have a low-E coating built in. This film brings some of that benefit to older glass without replacing the window.
Where it fits
Hot summers
Helps reduce heat gain through glass.
Cold winters
Helps retain warmth indoors.
Older windows
Whole-home use on windows without low-E glass.
Year-round
One film that works in both seasons.
Inside the film
Not to scale. Layers differ by manufacturer.
How it is made and fitted
- Optical-grade base. Clear polyester film carries the coating.
- Low-E coating. A very thin coating gives the low-emissivity effect.
- Adhesive. A mounting adhesive bonds the film to the glass.
- Hard coat. A scratch-resistant coating protects the surface during cleaning.
Not the best fit for
- Replacing new low-E windows.
- Windows that already have a low-E coating, where it adds little.
Good to know
- It is a film for existing windows, not new low-E glass.
- Low-E coatings can use very thin metal-based layers. If cell or Wi-Fi signal matters to you, ask for the spec sheet first.
- We check your glass first and may decline a film for a window.
Exact specifications are on the spec sheet we share with your quote. The warranty length is named on your quote; see our warranty page.
What to expect
From first request to finished glass
Tell us about your windows
Send us your address, the rooms and your main goal.
We check your glass
Glass type matters. We confirm the film suits your windows before we quote.
Get a quote and spec sheet
You get a clear quote with the film’s spec sheet.
Professional install
Kexova installs it and schedules the visit with you.
How it is made
Inside a ThermaCore Low-E film
Low-E (low-emissivity) film carries an extremely thin metal or metal-oxide coating, laid down in a vacuum chamber, that reflects radiant heat back to where it came from. That helps in cold weather by keeping warmth in, and in hot weather by limiting heat gain.
Window film starts as optical-grade polyester (PET), a clear plastic made in very thin, even sheets. Coatings are added in layers: dyes or ceramic particles, thin metal or metal-oxide layers applied in vacuum chambers, and a scratch-resistant hard coat. A pressure-sensitive adhesive and a protective liner go on the other side. The layers are laminated and cured, then slit into rolls and checked for clarity, coating evenness and defects before they ship.
Specs to ask for
Numbers that matter when you compare
Visible light
VLT is the share of visible light that passes through. Higher is clearer and brighter. Ask for the emissivity or U-factor improvement, where the maker publishes it, alongside VLT.
Total solar energy rejected
TSER shows how much of the sun’s total energy the film blocks, including heat. Low-E film is usually chosen for year-round comfort rather than the darkest look.
UV rejection
The share of ultraviolet rays blocked, which affects fading of floors, furniture and art.
Solar heat gain
Lower SHGC means less solar heat enters the room. It applies to the whole window, so ask for the film-on-glass value.
Glass compatibility
Film suits some glass better than others. We check your glass type and any maker restrictions before we quote.
What is covered
Ask for the film maker’s warranty and ours, including what each covers and for how long.
Exact figures come from the maker datasheet for the film we quote. We send the datasheet with your quote. Ask us and we will explain any number.
After install
Looking after it
Soft cloth, mild soap and a little patience in the first weeks keep this film clear for years.
Questions
What does Low-E film do?
It helps reduce heat gain in summer and heat loss in winter on glass you already have.
Will you check my glass first?
Yes. Glass type matters, so we confirm the film suits your windows before we quote. If a film is not right for a window, we will say so.
Where do I find the exact specifications?
The manufacturer’s specification sheet for the exact film comes with your quote. We do not publish performance figures on this page, because they differ from roll to roll.
What does the warranty cover?
The warranty length is named on your quote. See our warranty page for the draft terms.
Is Low-E film worth it in Texas?
It can help in both seasons, but solar-heavy windows often get more from solar control film. We can compare them for your glass.
Is it visible?
Many Low-E films look very light. Your sample shows the exact look.
More ThermaCore films
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Get a free quoteWindow film, matched to your glass and installed by Kexova.
Serving the greater Austin, Dallas, Houston and San Antonio areas.
Performance depends on the film, the glass and the window orientation. Specification sheets are provided at quote.
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