Do You Still Need Window Treatments With Impact Windows?
Nearly every window we measure in South Florida is laminated impact glass now, and the owner asks the same thing: the glass is supposed to block everything, so what is the shade for? Here is what the glass makers publish, what is left, and what we hang behind it.
Do you still need window treatments with impact windows?
Yes, for everything except UV and storm protection. Laminated impact glass blocks about 99% of ultraviolet light (PGT, Saflex and Cardinal all publish 99% or more) and, with the low-e or tinted laminate sold in South Florida today, keeps most of the sun's heat out: PGT's WinGuard packages publish solar heat gain coefficients of 0.22 to 0.33, Ply Gem's Mira impact 0.21 to 0.28, and the 2023 Florida Energy Code caps new windows at 0.25. That is the glass doing three-quarters of the heat work before any shade is hung, and it is why we no longer sell shades on the cooling bill behind new glass.
What impact glass does not do is everything else a window treatment is for. It passes a third to three-quarters of the visible light (visible transmittance 0.39 to 0.72 on the same documents), so the 4 PM glare on a west wall is still glare. It is transparent from outside at night the moment a lamp is on. It stops the UV share of fading and nothing else: the film industry's own figure is that UV and visible light together cause about 65% of fading and heat another 25%, so with the UV gone, light and heat still fade the rug. It has no closed position for a bedroom, and a 0.25 SHGC still means a quarter of the sun's energy arriving at the glass line on the afternoon side.
- Glare and the view: a 3% or 5% solar screen, chosen by colour for the view you want to keep; the glass already did the heat, so a lighter openness is often right.
- Privacy at night: a dual roller shade, a sheer with a lined drapery, or a blackout; nothing in the glass does this.
- Sleep: a blackout roller in side channels, or lined drapery.
- Fading: the glass took the UV; the shade or the lining takes the light and the heat on the exposures that matter.
- Window film: often sold as the "treatment" for impact glass, and PGT's warranty is void if aftermarket films are applied to its windows. The comparison is on window film vs solar shades.
Written by Exotic Shades & Draperies in Fort Lauderdale, where nearly every window we measure in a post-2005 tower or house is laminated impact glass. Every figure links to the glass maker's, the code's or the mill's document. The energy arithmetic behind "the glass does three-quarters of the work" is on our heat ranking page; this page is about what is left for the shade to do.
What impact glass blocks, and what it does not #
Seven things people buy window treatments for, against the published performance of laminated impact glass.
Swipe sideways to see every column.
| Job | Does impact glass do it? | The published figures | Source |
|---|---|---|---|
| Ultraviolet (UV) | Yes, almost all of it | PGT: the laminated interlayer "generally filters 99% of the sun's harmful UV rays" (below 380 nm); Saflex PVB 99% to 380 nm; Cardinal laminated "over 99%"; Andersen SmartSun 95% | PGT UV protection |
| Solar heat | Most of it, with a low-e or tinted laminate | PGT WinGuard SH7700 SHGC 0.33 (Energy Shield), 0.23 (Energy Shield Max), 0.22 (SolarControl LowE2); Ply Gem Mira impact 0.28 and 0.21; Vitro coated laminates 0.34 to 0.45; Florida code maximum 0.25 | PGT WinGuard data sheet |
| Visible light and glare | Only partly | Visible transmittance 0.39 to 0.72 on the same documents: Ply Gem Mira VT 0.50 and 0.39; Vitro Solarban 60 clear laminate VLT 72%, Solarban 70 64%, Solargray laminate 36%, Solarcool Solargray 16%. A third to three-quarters of the visible light still comes in | Vitro laminate brochure |
| Privacy at night | No | Any glass is clear from outside once the interior lights are on; even a reflective film gives "daytime privacy" only and "after dark, when interior lights are on, visibility from outside increases" (LLumar) | LLumar reflective film |
| Fading | The UV share only | The window film industry puts UV plus visible light at about 65% of fading and solar heat at 25% (IWFA); 3M says UV "contributes up to 40% of fading" and that even UV films "do not completely stop fading". PGT: "Visible light can accelerate fading." | IWFA on fading |
| A dark bedroom | No | Impact glass has no closed position; blackout is the shade's job | Blackout shades |
| Insulation | Modestly | U-factor 0.36 (Ply Gem Mira impact IG) to 0.56 (PGT WinGuard aluminum); the Florida code allows impact-rated windows up to U 0.65 in climate zone 2 | Florida Energy Code form R402 |
How to read your own window. Every new window carries an NFRC label with three numbers. Solar heat gain coefficient, 0 to 1: "low numbers resist solar heat, high numbers allow solar heat". Visible transmittance, 0 to 1: "the higher the number, the more natural light is let in". U-factor, 0.20 to 1.20: insulation, lower is better. The 2023 Florida Energy Code's prescriptive form sets SHGC at 0.25 maximum in climate zones 1 and 2, U-factor 0.40 in zone 2 (impact-rated windows may go to 0.65), and the University of Florida's IFAS extension calls SHGC "the most important consideration in selecting windows that are exposed to direct sunlight" in Florida, adding that "dark-tinted coatings can significantly reduce visible transmittance". A 0.25 window with a VT of 0.50 is the common case: a quarter of the sun's energy and half of its light come in.
What is left for the window treatment to do behind impact glass #
With UV and most of the heat handled by the glass, the treatment is chosen for light, privacy, sleep and the view, in that order.
Swipe sideways to see every column.
| Treatment | What it adds behind impact glass | The figures | Source |
|---|---|---|---|
| Solar screen, 3% openness (Mermet E Screen, Phifer SheerWeave 2410) | Glare, UV, view, heat at the glass line | E Screen 3% blocks 97% of UV (1% blocks about 99%, 5% 95%, 10% 90%); Phifer 2410 Brite White passes 17% of visible light with SHGC 0.27 on single clear glass, Charcoal passes 4% with SHGC 0.58 | Mermet E Screen spec |
| Solar screen, 5% openness (Phifer SheerWeave 2000, 4000) | View first, glare second | SheerWeave 2000 White passes 16% of visible light, SHGC 0.30; Charcoal 7%, SHGC 0.58; 4000 Greystone 8%, SHGC 0.43 | Phifer SheerWeave 2000 card |
| Blackout roller with side channels | Sleep, television, total privacy | The one job no glass does; the side channels close the light gap | Blackout shades |
| Dual roller shade (screen plus blackout on one bracket) | Daytime view and night privacy on the same window | The condo answer when the association wants white toward the street | Dual roller shades |
| Sheer plus lined drapery | Privacy, softness, a dark room when closed | Sheer by day, lined panel at night; the lining does the blackout | Drapery lining guide |
| Honeycomb shade | Insulation and a quiet room | The only product here with an R-value; details on the heat ranking | Heat ranking |
Glare
Pick the openness for the view, not the heat
Behind clear 1990s glass we specified 1% and 3% screens to fight heat. Behind 0.25 glass the heat argument is mostly spent, so the choice is how much of the view to keep against how much of the 4 PM sun to cut: a 5% screen on a south or east balcony, 3% on the west wall, dark colours for the sharpest view and the least glare, light colours when the room should stay bright. The numbers by colour are on dark or light solar shade fabric and openness 1% to 10%.
Privacy
Glass is a window at night, whatever it is made of
A screen reverses at night: with the lamps on, the street sees in through any solar screen, and through any impact glass. The bedroom and the bathroom get a blackout or a dual shade; the living room gets a sheer with a lined panel, or a dual roller with the screen for the day and the blackout for the night, white toward the street where the association requires it.
Fading and the gap
Keep the gap, and let the lining take the light
The UV is gone; visible light and heat still fade a rug and a sofa on the west side, so the lined drapery and the screen still earn their place there. One caution from the glass makers: an interior shade reflects energy back at the glass and raises its temperature, so on an inside mount we keep a vented gap and check the glass type before specifying sealed side channels on tinted laminates. The bulletins are on the heat ranking page.
Window film on impact glass: read the window warranty first #
Film is the treatment most often sold to impact-window owners, because it is cheap per square foot and promises the UV and heat figures the glass already delivers. Two documents matter before any film goes on laminated glass. PGT's residential warranty says it "shall be null and void" if "any other 'aftermarket' products, such as window films, are applied to the PGT product". 3M's own glass checklist lists "laminated glass in single pane or double pane" among the situations where a glass check and 3M's prior approval are required, and its film warranty covers thermal-shock breakage only on "recommended types of glass", to a maximum of $500 per window. A roller shade, a drapery or a honeycomb leaves the glass and its warranty alone. The full side-by-side, with film and screen figures and costs, is on window film vs solar shades.
Behind impact glass, from Miami to Palm Beach #
The towers on our building pages are glazed with laminated impact glass, and the question on this page comes up in every one of them. The newer version of it, whether electrochromic or switchable smart glass replaces the shade altogether, is answered on smart glass vs window treatments.
Sunny Isles Beach
Blackout in side channels, Turnberry Ocean Club
Floor-to-ceiling impact glass on the ocean, and the bedroom still needed to be dark: Lutron Sivoia QS blackout shades in side channels at Turnberry Ocean Club. The glass did the heat; the channels did the night.
Pompano Beach
Screens and blackouts on a new tower, Salato
At Salato, a new tower in Pompano Beach, the shades are Sonesse 50 rollers chosen for glare in the living areas and sleep in the bedrooms, wired through the building's own conduit.
Hillsboro Mile
Dual screens on an oceanfront house
At the Hillsboro Beach oceanfront home the master bedroom runs dual shades on Lutron Sivoia QS: a screen for the view by day over the water, a second layer for the night. Behind impact glass, that is the whole brief.
Impact windows and window treatments: questions
Do I still need window treatments if I have impact windows? #
Yes, for glare, privacy, sleep, the view and the light-and-heat share of fading. Laminated impact glass blocks about 99% of UV and, with today's low-e or tinted laminates (SHGC 0.21 to 0.33 on PGT and Ply Gem documents; Florida code maximum 0.25), most of the heat, but it passes a third to three-quarters of the visible light, is transparent from outside at night, and has no closed position.
Do impact windows block UV? #
Almost all of it. PGT says the interlayer in its laminated glass "generally filters 99% of the sun's harmful UV rays" below 380 nm; Eastman's Saflex PVB interlayer publishes 99% to 380 nm; Cardinal's laminated glass "over 99%"; Andersen's SmartSun glass 95%.
Do impact windows block heat? #
Most of it, if they carry a low-e or tinted laminate: PGT WinGuard SH7700 publishes SHGC 0.22 to 0.33, Ply Gem Mira impact 0.21 to 0.28, Vitro's coated laminates 0.34 to 0.45, and the 2023 Florida Energy Code caps new windows at 0.25. A clear laminate without a coating blocks far less heat; the NFRC label on the window tells you which you have.
Do impact windows stop glare? #
Only partly. The same documents show visible transmittance of 0.39 to 0.72, so between a third and three-quarters of the visible light still comes through. A 3% or 5% solar screen handles the glare; dark colours cut it most and keep the sharpest view.
Will impact glass stop my furniture and floors from fading? #
It removes the UV share only. The International Window Film Association puts UV plus visible light at about 65% of fading and solar heat at 25%; 3M says UV "contributes up to 40%" and that even UV films "do not completely stop fading". On east and west exposures a screen or a lined drapery still protects the rug.
Can people see in through impact windows at night? #
Yes. Any glass is clear from outside once the interior lights are on, and a solar screen reverses the same way at night. Night privacy needs a blackout, a dual roller shade or a lined drapery.
Which window treatment is best behind impact glass? #
Living areas: a 3% or 5% solar screen chosen for the view and the glare rather than the heat. Bedrooms: a blackout roller in side channels or a lined drapery. Rooms that need both: a dual roller shade. Insulation: a honeycomb. The heat case is weaker than behind old clear glass; the glare, privacy and sleep cases are unchanged.
Is window film a good idea on impact windows? #
Check the window warranty first. PGT's residential warranty is void if aftermarket films are applied to its windows, and 3M requires its own prior approval before film goes on laminated glass. Film also delivers the UV and heat figures the glass already has. The comparison is on window film vs solar shades.
What SHGC and VT should impact windows have in Florida? #
The 2023 Florida Energy Code's prescriptive form sets SHGC at 0.25 maximum in climate zones 1 and 2 and U-factor 0.40 in zone 2, with impact-rated windows allowed up to U 0.65. UF/IFAS recommends an SHGC of 0.25 or lower and calls it the most important number for windows in direct sun, while noting that dark tints cut visible transmittance.
Do interior shades stress impact glass? #
Glass makers say an interior shade reflects energy back at the glass and raises its temperature, and ask for a vented gap between shade and glass; none of their bulletins addresses laminated impact glass specifically. On an inside mount we keep the gap and check the glass type before specifying sealed side channels on tinted laminates; the bulletins are on the heat ranking page.
Where the numbers come from #
All documents accessed 17 October 2026. Figures are reproduced as the glass maker, the code, the mill or the trade association prints them. Makers revise their documents, and we will update the page when a figure changes.
- PGT Windows, UV protection: the laminated interlayer generally filters 99% of UV rays below 380 nm; visible light can accelerate fading. pgtwindows.com
- Eastman, Saflex UV bulletin: conventional Saflex PVB interlayers have a 99% UV screening capability up to 380 nm. saflex-vanceva.eastman.com
- Cardinal Glass, Technical Glass Guide: laminated glass blocks over 99% of UV; visible spectrum 380 to 780 nm. www.cardinalcorp.com
- Andersen Windows, coastal windows: SmartSun glass filters out 95% of UV. andersenwindows.com
- PGT, WinGuard SH7700 aluminum single-hung data sheet: SHGC 0.33, 0.23 and 0.22 by glass package; U-factor 0.56 and 0.57. d286k0zpa9aa1c.cloudfront.net
- Vitro Architectural Glass, monolithic laminate brochure: Solarban 60 clear laminate VLT 72%, SHGC 0.45; Solarban 70 VLT 64%, SHGC 0.35; Solargray laminate VLT 36%, SHGC 0.41; Solarcool Solargray VLT 16%, SHGC 0.34. www.vitroglazings.com
- Ply Gem, Mira impact double-hung specification sheet (NFRC): U 0.36, SHGC 0.28, VT 0.50; HPSC glass U 0.36, SHGC 0.21, VT 0.39. www.plygem.com
- Florida Building Code, Energy Conservation, 8th edition (2023), Form R402: SHGC 0.25 maximum in climate zones 1 and 2; U-factor 0.40 in zone 2; impact-rated windows up to U 0.65 in zone 2. www.seminolecountyfl.gov
- NFRC, the energy performance label: definitions of SHGC, visible transmittance and U-factor. www.nfrc.org
- University of Florida IFAS Extension, FY1045: SHGC is the most important consideration for Florida windows in direct sun; 0.25 or lower; dark tints reduce visible transmittance; outside treatments keep out more heat than indoor treatments. ask.ifas.ufl.edu
- LLumar, reflective window film: daytime privacy; after dark, with interior lights on, visibility from outside increases. llumar.com
- International Window Film Association, What to do about fading furniture and decor (2015): UV and visible light about 65% of fading, solar heat another 25%. iwfa.com
- 3M, UV protection and fading technical bulletin (2019): UV contributes up to 40% of fading; films do not completely stop fading. multimedia.3m.com
- U.S. Department of Energy, Energy Saver, energy-efficient window attachments, as quoted by Consumer Reports: highly reflective blinds can reduce heat gain by around 45%; medium-coloured draperies with white plastic backings by 33%. www.consumerreports.org
- Mermet USA, E Screen grouped specification sheets (April 2025): UV blockage approximately 99% (1%), 97% (3%), 95% (5%), 90% (10%). mermetusa.com
- Phifer, SheerWeave 2410 swatch card: Brite White Tv 17, SHGC 0.27 single and 0.21 insulating; Charcoal/Grey Tv 4, SHGC 0.58 and 0.36. www.draperinc.com
- Phifer, SheerWeave 2000 sample card: White Tv 16, SHGC 0.30; Charcoal/Gray Tv 7, SHGC 0.58; UV approximately 95%. www.trivantage.com
- PGT, all residential products limited warranty (2020): null and void if aftermarket products such as window films are applied. www.pgtwindows.com
Discerning homeowners, designers, and developers across South Florida trust Exotic with their most important spaces.
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Exotic Shades & Draperies, Fort Lauderdale and Miami Beach
Exotic Shades & Draperies is a South Florida window-treatment company that designs, sews and installs its own work: Lutron and Somfy motorized shades, custom draperies sewn in our Fort Lauderdale workroom by five in-house seamstresses, plantation shutters and blinds. Established in South Florida in 2024, backed by more than 20 years of window-treatment manufacturing and installation experience. Lutron certified dealer, Somfy Expert, Crestron and Control4 integration. The same in-house team measures, installs and programs every project; when shading has to integrate with another control system, we bring in our smart-home partner Adom Smart Home.
Fort Lauderdale workroom and showroom
4539 Powerline Rd, Fort Lauderdale, FL 33309 · 954-881-9331
Miami Beach showroom
500 South Pointe Dr #150, Miami Beach, FL 33139 · 954-872-9007
Where we install
Miami-Dade, Broward and Palm Beach counties: Miami Beach, Sunny Isles and Aventura through Hollywood, Fort Lauderdale and Pompano Beach to Boca Raton, Delray Beach and West Palm Beach, with projects in the Caribbean and New York.
How a project runs
Free in-home measurement, a written quote from the same engine as our published prices, fabrication in our own workroom, installation and programming by our own team, and service on the systems we install.
Window treatments behind impact glass, from Miami to Palm Beach
Screens chosen for the view and the glare, blackouts and dual shades for the night, lined drapery where the light still fades, a vented gap kept at the glass. The same in-house team measures, builds, installs and programs from Miami Beach to West Palm Beach.
New impact windows and no idea what to put on them?
One free hour with our team routinely saves owners thousands in avoidable mistakes. Book a private, complimentary consultation - we read the NFRC label on your glass, tell you what it already does, and quote only what is left to do.