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Does upgrading to impact resistant windows make sense?

Trace E
last month

Just learned that our development uses Mi windows, and I'm reading not-so-great things about that company here. We're building on the coast of central florida, and while we're getting shutters as part of our new home package, we had planned to upgrade to the impact resistant windows on the entire house, at the cost of $10K.


But if the windows are made by Mi, and we have no other choices, are we unnecessarily spending 10K on crappy windows? Or are we spending 10K to get windows that are slightly-less-crappy? Our research led us to believe we'd be getting added benefits of increased safety from crime as well as an increased sound barrier. But part of that info came from family members who have impact windows made by a different manufacturer.

Comments (45)

  • Trace E

    From the spec sheets they provided:

    IMPACT

    RESISTANT

    185

    SINGLE-HUNG

    Designed specically with coastal regions in mind,

    the  aluminum window line combines precision

    and reliability for homes in storm-prone areas.

    The  single-hung has high DP ratings and is

    available with the StormArmor

    impact-resistant

    package, making it the ideal single-hung window

    for new construction projects in any location.

    PERFORMANCE FEATURES

    ■ Dual-pane insulated glass helps maintain constant

    interior temperatures year-round

    ■ Warm-edge spacer system maximizes energy eciency

    and improves seal performance of insulated glass units

    ■ Sweep lock system at meeting rail helps maintain the

    home’s security

    ■ Interlock at meeting rail helps reduce air inltration

    2" sill height

    Standard

    Optional

    Sweep

    lock

    2" frame depth

  • Denita

    For $10k I would upgrade to impact windows in a heartbeat.

    Trace E thanked Denita
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  • cpartist

    While I didn't find the MI windows great, (I saw them here in SW FL in a David Weekly build and they didn't seem as solid as my PGT windows) I think they're still better than shutters. I agree with Denita.

    Trace E thanked cpartist
  • Trace E

    Thanks for the responses. I wasn't expecting people to be in favor of them. As a newbie soon-to-be Floridian, does it matter that we're inland by several miles? Would people still spend the money on impact windows that don't get favorable reviews if their home isn't right on the water? (I think I might already know the answer to this question . . . )

  • Leslie NE. Florida coast, zone 9A

    Some of the worst wind damage we saw after hurricane Matthew was several miles inland. Get the best glass you can.


  • cpartist

    How many miles inland? Have you ever looked at the total width of a hurricane and how far out the strongest bands can be?

    I think you know your answer.

  • cpartist

    Actually take a look where Homestead FL is. During hurricane Andrew in August of 1992, (I'll never forget it as I watched it on tv after giving birth to my daughter that day), Homestead was practically leveled and it's why most of FL now follows Miami/Dade building codes for houses.

    Trace E thanked cpartist
  • Trace E

    We'll be about 10 miles inland. Again, shutters are included with the home, so we'd definitely have protection. I just wasn't sure about spending money on window upgrades if they're not impact windows from a well-regarded manufacturer.

  • Denita

    I'm further inland then you and impact windows are well worth it. You are only 10 miles inland. As cpartist mentions, research hurricane winds and patterns for the last few decades. Depending upon the type of shutters you get with the house, they can be a real PITA to put up when everyone is scrambling the week before a hurricane lands.

  • cpartist

    When a hurricane is heading your way, depending on how close, it means putting together all you need, shopping or hightailing it out. Either way, do you really want to be putting shutters up? Do you really want to be getting up on ladders?

  • David Cary

    As a non-Floridian, what type of shutters are we talking about. Are they true hurricane shutters? Like roll down and metal or just operable wood (of fiberglass) shutters?

    Is this a ranch or 2 story?

    We have impact windows on a coastal NC home. They are quiet and I do feel somewhat safer from criminals. That being said, I worker broke one fixing up the house after the hurricane. A crack - not a true violation. I paid less than $10k total for windows in that house (2 story -2100 sqft with windows as expected on an oceanfront house). That was 9 years ago. ViWinCo vinyl - crap windows for sure. But I would do it again.

    As far as the shutters - and putting them up - how long does that really take? That is a huge variable that we don't know the answer to.

  • remodeling1840

    We were on vacation when one of the hurricanes headed straight for our house. How do you close your shutters when you are 1000 miles away? Many snowbirds close the shutters when they leave—everyone who drives by their property knows no one is home....

  • ulisdone

    Research homeowner’s insurance rates. You used to get a credit for shutters and impact windows. That may have changed in the last few years as the insurance industry struggles with costs.

    Shutters have the advantage ( depending on proper coverage and type) of sealing the edges of openings from wind borne rain. Because of the relatively mild weather in Florida, construction detailing at openings is not always the best, and yet homeowners are unaware of this in day to day life. But In a hurricane rain can be blown through the edges of windows and doors. So shutters with good overlap are best.

  • Denita

    @ulisdone, you still get a discount for impact windows and shutters. You have to have a wind mitigation report done and supply it to the insurance co, but they last 5 years. In a new home, the discounts should be substantial if the proper wind mitigation improvements were installed.

  • Trace E

    We did check on insurance and both companies we contacted told us there would be no difference in savings between windows and shutters. So that doesn’t help us with our decision.

  • Denita

    Make sure to use a good insurance broker. HOI here is expensive here in Florida, especially S Fl. You won't have as large a premium because you are in Central Fl (right?) and you will have a new home.

    Trace E thanked Denita
  • Shannon_WI

    A friend of mine is selling her condo in Jupiter. The building has hurricane shutters on all the apartments’ windows, so my friend never spent the money on hurricane-resistant windows. In the past umpteen hurricanes, her apartment has not had any water infiltration or damage with the shutters on. Yet she is now finding that decision to be a huge disadvantage for selling her place. Most of the comparable condos for sale in her area have hurricane-resistant windows, and quite a few have the building’s original shutters plus hurricane-resistant windows, “belt and suspenders”. Jupiter is frequently near Ground Zero for hurricanes.

    My friend is willing to reduce the price of her condo significantly to compete against the other condos that have hurricane windows. But it’s not just about money - buyers are saying “why should I buy your condo and have to deal with the hassle and stress of replacing the windows, when there are so many other condos for sale that already have them installed?”

    My friend’s realtor told her that the hurricane-resistant windows in her 2600 s.f. apartment would cost around $50k in Jupiter.

  • Denita

    ^Yep. I see this all the time. Jupiter is one of my selling areas.

  • PRO
    Evolution Hurricane Shutters, LLC

    Let me see if I can inject some important information about ANY impact window. There is a lot of misinformation floating around and I will try to share what I know. I'm no window expert, but i do know a little about what happens in Florida. I hope that someone with more window knowledge can add to or improve or correct what I am putting in print.


    I feel that the most important thing to do when researching windows is to check the performance specifications. There are 2 categories - hurricane testing and standard window testing


    Hurricane testing

    • design pressure - although the design pressure is important, it is an approximate measure of how much wind pressure the installed window (or shutter) can withstand without failure. There is a safety factor (which I believe is 30%) that actually REDUCES the performance of the window. In other words, when a window has a design pressure of 60psf, it has been tested at an additional 30% of that figure. 60psf x 30% = 78psf.
    • large missile impact - this test involves shooting a 9lb. 2x4 at the window (or shutter) in 3 difference places to see if the 2x4 will penetrate the product. Impact windows are sacrificial products which means that they are DESIGNED to break but not allow the large missile to product a large hole to allow pressurization of the structure. Contrary to what you might think, impact windows aren't "hurricane proof" or "shatterproof" and they will NOT survive a large missile impact during a storm. They WILL break, they will allow shards of sharp glass to be hurled into the living space behind them and they will need to be replaced. Breakage is not limited to hurricanes, either. Debris from lawn equipment and vandalism can also cause breakage.
    • cyclic test - this test involves pressurizing the window (or shutter) 9200 times - 4600 with positive pressure and 4600 times with negative pressure. It starts at a low pressure and each pressure cycle is increased up to the predetermined design pressure. In the previous example, that would be 60psf.

    Window testing

    • water penetration - this test indicates the high point that the unbroken window prevents water leakage. If the value is 20 psf that means that any winds pressure above that value are at risk of leaking. Leaking means water damage of some degree is likely to occur.
    • air infiltration - this testing tells you how much air will bypass the seals around the glass and between the sashes and frame and anywhere else.

    Please note that both of these tests are performed only on a new, intact window and NOT on an impact window after it has been broken. Impact windows are NOT required to stop water or air. The impact designation only requires the window to pass the hurricane testing and not the window testing.


    Impact windows are designed to break when hit, cause flying pieces of glass to be hurled into the living space and do not offer water penetration protection at hurricane force wind levels. They are expensive to replace and because of these issues, they make a very poor 1st line of defense against hurricanes. They do quite well at protecting against quick forming storms like micro-bursts or severe wind storms, but most "affordable" products will probably fall short of providing total protection during a hurricane event.


    There's no substitute for research. Knowledge is power and an educated consumer will be a happy consumer. Good luck on your home improvement project.


  • Lisa

    I'm in central FL and replaced all the windows and sliding doors with PGT windows/doors that meet Miami-Dade standards. I also replaced all the exterior doors with impact/wind resistent doors. The house is quieter, cooler, and cleaner. This article is old but still has some good points to consider.

    https://www.houzz.com/discussions/2646179/questions-about-pgt-and-impact-glass-in-fl

  • oberon476

    I agree with There's no substitute for research. Knowledge is power and an educated consumer will be a happy consumer, so I am going to address some of the points of your post.

    - design pressure - although the design pressure is important, it is an approximate measure of how much wind pressure the installed window (or shutter) can withstand without failure.

    Design Pressure is part of the three-part air, water, structural test that determines much about a window's overall performance. Air infiltration is the first phase, water penetration is next, and structural is the third part of the test.

    Windows are tested for air infiltration simulating a 25mph wind (1.56PSF pressure loading), and is independent of DP, while water infiltration and structural are based on the window design pressure. Water infiltration is tested at 15% and structural is tested at 150% of DP rating. A window with a DP30 is tested for water infiltration at 4.5psf (or 15% of 30psf) while a window with a DP40 is tested at 6psf (or 15% of 40psf), and so on.

    - There is a safety factor (which I believe is 30%) that actually REDUCES the performance of the window. In other words, when a window has a design pressure of 60psf, it has been tested at an additional 30% of that figure. 60psf x 30% = 78psf.

    Windows are structurally tested at 150% of the design pressure - a window with a rated design pressure of 60psf (~ 154mph) is tested for structural at 90psf (190mph).

    I have no idea what you are trying to suggest by "...actually REDUCES the performance of the window." ? In what way does a safety factor reduce the performance of anything?

    Also, since design pressure in psf is the square of the ratios of the wind-speed in mph, it’s relatively easy to calculate the equivalent windspeed performance (if so inclined) if you know the design pressure rating.

    - large missile impact - this test involves shooting a 9lb. 2x4 at the window (or shutter) in 3 difference places to see if the 2x4 will penetrate the product.

    Depending on the test, and the product being tested, there could also be only one or two impacts required.

    Impact windows are sacrificial products which means that they are DESIGNED to break but not allow the large missile to product a large hole to allow pressurization of the structure.

    That entire statement is ludicrous...Windows are made of glass, impact windows are made of glass. Hit glass hard enough and it's going to break. To suggest that the glass is "designed" to break as a "sacrificial" product is simply not the case.

    Contrary to what you might think, impact windows aren't "hurricane proof" or

    "shatterproof" and they will NOT survive a large missile impact during a storm.

    I am curious if you have verified data detailing exactly how many impact windows have been struck by flying 2x4's during a hurricane, since you are saying that they won't survive a large missile impact during a storm.

    Actually, it's quite possible to fabricate a laminated glass lite that won't break when impacted by a 2x4 at 50fps (or a lot faster - re: tornado impact resistant glass), but a viable product has to meet (at least) three simple objectives: 1) is it practical, 2) is it affordable, 3) is it effective. Unfortunately, fabricating laminated glass that won't break when impacted by the 2x4 might be effective, and may or may not be practical, but affordable is not in the picture unless you are willing to spend a great deal of money for them.

    They WILL break, they will allow shards of sharp glass to be hurled into the living space behind them and they will need to be replaced.

    Have you ever witnessed the test?

    If the impact is to a monolithic laminated glass (no IG), then there will be some spall (glass dust), but NO shards of sharp glass hurled into the living space...If the impact is to a laminated IGU and the laminated glass is the inside pane, then any broken glass from the outside non-laminated lite is stopped from entering the living space by the laminated glass - broken or not, NO shards of sharp glass hurled into the living space...if the laminated lite is to the exterior and the inner lite is the non laminated then it probably will break into large (and small) shards, and they will be dangerous, but saying that they are going to be hurled into the living space is overstated . The glass may break, but the laminated lite has absorbed most of the energy of the impact and that will limit the damage from raw broken glass to the interior. As a general rule, I much prefer impact windows with the laminated lite to the interior for that reason.

    Bottom line in any case, if you are in your home during a hurricane, standing in front of your windows (and I don't care what's protecting them) is not a really good idea).

    Breakage is not limited to hurricanes, either. Debris from lawn equipment and vandalism can also cause breakage.

    Debris from lawn equipment, and vandalism, and the odd baseball or golf ball can absolutely break windows...impact resistant or not. What's your point? Having laminated glass in the window may not prevent breakage, but it can help prevent injury.

    • cyclic test - this test involves pressurizing the window (or shutter) 9200 times - 4600 with positive pressure and 4600 times with negative pressure. It starts at a low pressure and each pressure cycle is increased up to the predetermined design pressure. In the previous example, that would be 60psf.

    Actually 9000 cycles divided into eight different pressure ranges, four positive and four negative

  • millworkman

    Top notch post and 100% oberon476.

  • M Miller

    Speaking of shooting a 2x4 at the window or shutter - for anyone who has 6 minutes to kill with some interesting footage from Ask This Old House show of a testing facility doing exactly that. It's also entertaining due to the homeowner's and Tawmmy Silva's deadpan New England commentary ("OK cheapskate let's see what happens").



  • unser

    I live on the east coast of Florida. Bought the house with crappy aged aluminum windows (with storm panels). We needed to replace a few windows due to corrosion which rendered them inoperable. After much thought we opted to go for impact windows. Yes, it’s quieter inside. No, we haven’t noticed a decrease in our electric bill. The biggest, advantage, for us, has been not having to exist in a dark, shuttered house when preparing for a hurricane. I’m glad we did it.

  • PRO
    Evolution Hurricane Shutters, LLC

    Oberon,


    If I understand your explanation of window testing for water penetration correctly, windows are not tested to prevent water penetration at hurricane wind speeds.....or maybe I'm not comprehending your statements correctly.


    My statement regarding impact performance was my mistake.....When i mentioned the reduction of the window performance by 30% due to a safety figure calculation, I inadvertently left out the word "specification". The performance of the window isn't reduced, but rather the stated figures were actually lower than the performance that actually occurred during the laboratory testing. My intent was to show that even though the specifications on the label read one figure, the testing was performed at a higher one, meaning that the window will perform at higher wind speeds (or wind pressure) than the ones stated. In other words, "the window performance specifications are reduced."


    "Large missile impact testing" in the State of Florida requires 3 impacts prior to the cyclic testing. If your product fails to prevent penetration or allows pressurization of the interior of the structure, it's a "fail". In the State of Florida it is illegal to "sell, offer or advertise" any product as hurricane protection if it is not registered with the State of Florida or Miami-Dade. If it doesn't pass the testing, it doesn't get registered. I don't understand your opposition to the fact that an Impact window must sacrifice itself to pass the impact test. Or maybe I am misunderstanding your statement. As I see it, if it has to break to do it's job, it's no longer useful as a window and has thus, sacrificed itself.


    Your statement that windows made of glass are going to break when impacted is absolutely correct. Unfortunately, many hurricane impact window representatives fail to stress this to buyers. In the real world, many people who have impact windows installed in their homes truly believe that their windows are "hurricane proof" and "shatterproof". I hear it every day on the phone and at every home show or hurricane expo. It is unfortunate that it is allowed to be a commonplace belief. Anyone who has witnessed a hurricane impact test or even watched a YouTube video that shows the backside of the window at the moment of impact will see for themselves how foolish and dangerous both of these terms are. I challenge anyone to shoot a 9lb. 2x4 traveling at 50fps at a 24" x 30" impact rated window and catch the debris from the backside. I guarantee that you will find more than just "dust". Your statement of standing clear of any window during a storm should be mandatory in any hurricane impact window sales presentation. I'm not a window expert like you, but to my knowledge, no commercially available hurricane impact window for residential use is even tested for shatter resistance. Please correct me if I'm wrong.


    As I stated previously, hurricane impact windows are good for certain applications, but as a first line of defense against the forces of a hurricane, they fall short. Are they better than regular windows? Of course they are. Are they going to reduce the amount of damage to your home? Of course they will. Will they prevent you from having any damage to your home or property? Most likely not. If they don't break, they still are susceptible to water leakage. If they do break you will have a mess to clean up, the expense of repurchase (even if you have insurance), the hassle and delay of replacement and the boarded up opening that you have until your replacement window gets installed.


    I hope that I have clarified my previous statements. Thanks for your time.















  • cpartist

    Evolution correct me if Im wrong but it appears your shutters are permanent meaning one can no longer open a window for fresh air? Plus they look downright ugly on the house.

    If that's the case, I'll stick with my PGT wind impact rated windows. Yes the outside glass will break, but the middle layer will protect my house from glass breaking on the inside and from water intrusion.

  • ulisdone

    If your windows break in a hurricane your roof is likely the next thing to go.

  • PRO
    Evolution Hurricane Shutters, LLC

    cpartist. If a dealer calls me and their customer wants use our product and still be able to open the windows, he/she has 2 options. They can order the shutter with the option of having the unbreakable panels made removable or they can opt for the egress version that locks from the inside and allows the shutter to be opened in case of emergency.


    Most homeowners purchase our shutters because they are virtually unbreakable, they offer an distortion-free view of the outside, they don't have to be put up and taken down with every storm, they quiet the home and they save energy. The fact that they and are the best looking window protection available is just icing on the cake. They aren't windows, but they are nearly impossible to spot from the street. For folks who want to protect their impact window investment, the product does a great job. The UV filtering characteristic will also protect the window frames and seals from deteriorating and help the windows last longer. If what I have read is true, the "lifetime warranty" of a PVC window in Florida is 7 years.


    As you have stated, your impact windows will break when struck. If they are hit hard enough (as in the large missile impact test), both the outer tempered lite and the inner laminated lite will be broken and you will be stuck with all of the cost and inconvenience of having to replace it. Hopefully you will be able to purchase a window that matches the ones that you have. If you're stuck buying something that doesn't match what you have, you'll be stuck with it.


    Check with the window manufacturer to see their guarantee on preventing water intrusion both before and after the window has broken. That way you can take them to court when your floors suffer water damage when they leak. The better way to protect against window breakage and water intrusion is to install some type of shutter over your windows. That way you won't have to worry about them breaking or leaking in the first place.


    Just some food for thought.

  • oberon476

    Evolution,

    Thanks, I always enjoy an interesting discussion in here....

    If I understand your explanation of window testing for water penetration correctly, windows are not tested to prevent water penetration at hurricane wind speeds.....

    AAMA 501.1-17, Standard Test Method for Water Penetration of Windows, Curtain walls, and Doors Using Dynamic Pressure, establishes the criteria for water penetration (title kinda gives it away).

    Impact requirements and performance are governed by either TAS 201, 202, and 203, or ASTM E1886 and ASTM E1996.

    Testing for air, water, and structural is not specific to impact rated windows. Windows that are never intended for hurricane applications are tested to these requirements as an industry standard. Design pressure is set prior to and for this testing and not to meet the requirements of impact/cycle testing....sort of, because window companies often set a specific (higher) DP requirement for their impact products that is more ambitious that what they might need for non-impact windows, and construct product to meet that requirement. But that doesn't

    Impact and cycle requirements were created following hurricane Andrew as part of the greater effort to help avoid the sort of cataclysmic damage that Andrew did to south florida. Impact/cycle testing is based on the performance of the entire window system and not the individual components of the window.

    "Large missile impact testing" in the State of Florida requires 3 impacts prior to the cyclic testing. If your product fails to prevent penetration or allows pressurization of the interior of the structure, it's a "fail".

    Both TAS and ASTM require three specimens to be impacted and cycled, but how many impacts to each specimen is dependent on what is being impacted.

    TAS 201 large missile and ASTM E1996 level D, wind-zone 4, both require two impacts to the glass, and a third impact IF the unit (patio door or window) has a meeting rail, or astragal, or mull, etc. The third impact will be to the meeting rail, et al. If the window is fixed or doesn't have any sort of meeting rail (casement), then the unit requires only two impacts to the glass.

    If testing to ASTM wind-zone's 1 - 3, then only a single impact to the glass is required, no matter what is being tested.

    Your statement that windows made of glass are going to break when impacted is absolutely correct. Unfortunately, many hurricane impact window representatives fail to stress this to buyers. In the real world, many people who have impact windows installed in their homes truly believe that their windows are "hurricane proof" and "shatterproof".

    I have heard this as well. It's very unfortunate that uninformed (or unscrupulous) people would say this, and while it does happen. I once visited a smaller window company to consult because they were having laminated breakage issues on their production line. I watched as their line operators SLAMMED the glass down into the sash, breaking it as often as not. When I asked what they were doing, I was told that this was impact glass and it was supposed to be unbreakable. Amazing...

    Anyone who has witnessed a hurricane impact test or even watched a YouTube video that shows the backside of the window at the moment of impact will see for themselves how foolish and dangerous both of these terms are. I challenge anyone to shoot a 9lb. 2x4 traveling at 50fps at a 24" x 30" impact rated window and catch the debris from the backside. I guarantee that you will find more than just "dust".

    I have witnessed or performed the impact test well over three thousand times in the past 20 years or so in pretty much any configuration that anyone can come up with. I stand by what I said in my previous post, with the caveat that "spall" is the correct term rather than dust, but I wasn't sure who might be familiar with that term. Consider spall to be "big dust" mixed with "regular dust".

    ...but to my knowledge, no commercially available hurricane impact window for residential use is even tested for shatter resistance.

    I am not sure i know what you are asking....

    ...but as a first line of defense against the forces of a hurricane, they fall short

    Obviously, I strongly disagree, and so do the insurance companies and building codes

    Will they prevent you from having any damage to your home or property? Most likely not.

    Again, I strongly disagree. This Texas home survived hurricane Ike when no other building along this portion of the coast did. It had hurricane windows installed. None of the windows were broken by the storm.

    This is not unique, generally impact windows weather the storm without damage.


    ...the hassle and delay of replacement and the boarded up opening that you have until your replacement window gets installed.

    One of the real advantages of impact windows is that you don't have to board them up if they happen to be broken. They are fine as they are until the glass can be replaced.

  • PRO
    Evolution Hurricane Shutters, LLC

    Oberon,


    Thank you for helping me to understand more about windows and their testing. I guess that the point that I'm trying to make is that I have not yet seen a required test for impact windows to prevent water penetration at hurricane wind speeds.....or is there one and I just don't know about it?


    Regarding large missile impact testing, I guess that I should have been more specific. My experience is with shutter testing and for Category 5 impact testing our 3 clear span 4' x 8' specimens were subjected to 3 large missile impacts in 3 different locations - no breakage or even a crack.


    ..but to my knowledge, no commercially available hurricane impact window for residential use is even tested for shatter resistance.


    I'm asking if there is a test to determine the "shatter resistance" of a hurricane impact window and if not, why not? If a manufacturer is going to make a claim of such, shouldn't there be some way to determine to what degree it resists shattering? Just curious that if you would want to stand behind an approved impact window during the test if all you expect is "dust"?

    ...but as a first line of defense against the forces of a hurricane, they fall short

    Obviously, I strongly disagree, and so do the insurance companies and building codes


    I can only tell you that in Florida, there is already talk in the insurance industry that payment for wind damage claims on impact windows will be made only once. After that, the windows will need to be protected by shutters to prevent any subsequent loss. The high cost of the replacement windows is what they term as a "preventable loss" and, of course, any time that they can avoid paying out a claim they will certainly work in that direction.

    Will they prevent you from having any damage to your home or property? Most likely not.

    Again, I strongly disagree. This Texas home survived hurricane Ike when no other building along this portion of the coast did. It had hurricane windows installed. None of the windows were broken by the storm.


    Yes, none of the windows were broken, but no mention was made of water penetration. Is it possible that the floors/walls had water damage? Many times this information is not reported on nor investigated.

    ...the hassle and delay of replacement and the boarded up opening that you have until your replacement window gets installed.

    One of the real advantages of impact windows is that you don't have to board them up if they happen to be broken. They are fine as they are until the glass can be replaced.


    Once an impact window has been subjected to a large missile impact test do they leak? Is there an ASTM test method for that? Also, the sounds made when the wind blows against the broken glass has a bit eerie sounding. Most glass companies in our area board them up to avoid water leaks and the creaking sounds.


  • oberon476

    Evolution,

    My apologies for presuming, and please feel free to correct me if I am wrong, but based on what I see here, you sell hurricane shutters from one particular company. They are the basis of your knowledge and your experience.

    Hurricane shutters have one application, one purpose, and that's to protect a home or other building from flying debris during a hurricane; something some shutters are much better at than are others. Hurricane shutters are stored and forgotten except when needed. When they are needed they are removed from storage, installed, and trusted to succeed at their only purpose. After the storm they are uninstalled and returned to storage until they are needed again. Testing and performance data for shutters is based entirely on their single purpose.

    Impact windows are first of all...windows. Every day of the year they do what all windows are required to do, plus they passively protect when needed. They are in use 24/7/365 no matter the environment where they are being used. There are numerous ASTM and ANSI tests and certifications available for window performance.

    The vast majority of impact windows are going to to be dual or IG glazed, two lites separated by a spacer. One of those two lites is going to be laminated, the other lite could be annealed, heat strengthened, tempered, or in rare cases, also laminated. A much smaller number of impact windows, where allowed by code, are glazed using a single monolithic laminated lite.

    I guess that the point that I'm trying to make is that I have not yet seen a required test for impact windows to prevent water penetration at hurricane wind speeds.....or is there one and I just don't know about it?

    There is no specific requirement to test windows for water penetration resistance at hurricane force winds...Shutters exist for one reason and testing is based on that one reason - so it's easy to answer yes or no for shutters, but windows are a lot more complicated. Water penetration testing is a window requirement whether the window is intended for impact or not and the level of testing is determined by the window manufacturer to meet their requirements.

    Windows are not If all windows were fixed, non-operable, it would be easy to say that they could prevent water leakage during hurricane force winds, but most windows aren't fixed and the do open and close which does make a difference in potential wind and water penetration.

    I'm asking if there is a test to determine the "shatter resistance" of a hurricane impact window and if not, why not? If a manufacturer is going to make a claim of such, shouldn't there be some way to determine to what degree it resists shattering? Just curious that if you would want to stand behind an approved impact window during the test if all you expect is "dust"?

    Do you mean shatter as in big shards of glass flying in the room or do you mean simply the glass breaking?

    Once an impact window has been subjected to a large missile impact test do they leak? Is there an ASTM test method for that?

    Leak how? Where?

    Also, the sounds made when the wind blows against the broken glass has a bit eerie sounding.

    What sort of sound? This is a new one on me and I was involved with this for over 20 years. It's like saying "studies have shown...". Without reliable data to back up the claim has no real meaning.

    Most glass companies in our area board them up to avoid water leaks and the creaking sounds.

    How many is "most"? When and how many impact windows have you seen that were broken and then boarded up? Once again saying "studies have shown..." without reliable data to back up the claim has no real meaning.

    I can only tell you that in Florida, there is already talk in the insurance industry that payment for wind damage claims on impact windows will be made only once.

    Actually, this idea was originally introduced by shutter manufacturers, not insurance companies. No idea if it ever gained traction with the insurance guys since I retired.

    A lot of your questions are based on preconceived ideas and assumptions that I suspect you have been taught as a shutter salesman, unfortunately I can't see that you have any knowledge about impact windows and that makes it tough to reply...basically we don't speak the same language.

  • PRO
    Evolution Hurricane Shutters, LLC

    Oberon,


    Thank you for your clarifications on a few things. Your opening paragraph states{


    My apologies for presuming, and please feel free to correct me if I am wrong, but based on what I see here, you sell hurricane shutters from one particular company. They are the basis of your knowledge and your experience.

    Yes, you are presuming. Thank you for apologizing in advance.


    Hurricane shutters have one application, one purpose, and that's to protect a home or other building from flying debris during a hurricane; something some shutters are much better at than are others.

    Once again, you have presumed and it's understandable because you are more well educated on the subject of windows. That is why I appreciate your information in that arena and not shutters. Some forms of hurricane protection only have one application - others provide other benefits like shading, security, energy use and noise reduction, etc. Some types are removed and stored while others are not. Their testing for hurricane protection is mandatory in Florida and a couple other states and is meant to protect the uneducated consumer from unscrupulous entities that In some instances, prey upon ignorance to profit.


    Water penetration testing is a window requirement whether the window is intended for impact or not and the level of testing is determined by the window manufacturer to meet their requirements.

    If you were questioned regarding the water-tightness of impact windows, and as a window professional, what would you recommend that the OP look for in performance specifications in that specific area? Or better yet, what window specs would you look for if you were putting new windows in your own Florida home? Or would you opt for a combination of windows with shutters for superior protection and not rely solely on windows to provide adequate hurricane protection?


    Do you mean shatter as in big shards of glass flying in the room or do you mean simply the glass breaking?

    ".....big shards of glass flying into the room...." How big of a piece would you deem as "dangerous"? Is anything big enough to draw blood big enough?...or put out an eye? I'll let you decide that one. As I said before, witnessing a large missile impact test in person or on YouTube where you see the backside of the glass upon impact will be enough to convince anyone that the choice of the term "shatterproof" is a stretch, at best.


    Leak how? Where?

    Leak water - anywhere that would promote interior water damage. Isn't that what we have been discussing?


    What sort of sound? This is a new one on me and I was involved with this for over 20 years. It's like saying "studies have shown...". Without reliable data to back up the claim has no real meaning.

    Once again, anyone who has witnessed the cyclic pressure test of an impact window is very familiar with the sound that is generated from the pieces of broken glass grinding against each other resulting from the movement from wind.


    For this reason and the increased chances of water from subsequent rainstorms causing damage, shattered impact windows are boarded up. If you call up a window company after a storm to get an estimate on getting your shattered impact window replaced, be assured that before they leave they will recommend boarding the window up for those reasons.


    I can only tell you that in Florida, there is already talk in the insurance industry that payment for wind damage claims on impact windows will be made only once.

    Actually, this idea was originally introduced by shutter manufacturers, not insurance companies. No idea if it ever gained traction with the insurance guys since I retired.

    Which shutter manufacturers introduced this idea? Without naming specific companies, would this be an example of "....studies have shown"? As a manufacturer, this company was never, ever invited and never offered an opinion on the subject. I think that I speak for many when i say that if the insurance industry wants to find a way to lower it's liability in paying out claims, they won't need the assistance of the shutter industry to do it. They already have the data that prove that the replacement cost of just one impact window is significant.


    So we are still lacking an answer to the OP's original question of "Does upgrading to impact windows make sense?" I think the answer lies with the question of "How much total hurricane protection are you looking for?"




  • oberon476

    The following is long, somewhat detailed, and probably boring as heck for most people, but I am including it because I am trying to share details of how windows, specifically impact related work.

    There are (is?) something over 1000 window companies in North America, Window and Door magazine has an annual issue that lists the top 100 biggest companies. The very largest companies have sales in the multibillion dollar range, but by the time they reach 100, sales are less than 15 million dollars annually. An huge drop from number one to number 100, but more to the point, there are another 900+ who have sales less than 15 million dollars a year.

    All of the bigger companies offer impact windows, but not necessarily in all of their product lines or all of their product styles within certain lines. Many smaller companies also offer impact windows, but I don't have a clue how many do or don't.

    Windows are available in wood, wood clad aluminum, wood clad vinyl, vinyl, aluminum and fiberglass, and other possible options.

    Window styles include fixed, casement, single-hung, double-hung, horizontal sliders or gliders, awning, hopper, tilt-turn. And various glass door options ranging from basic sliding patio doors to massive moving walls that start at over $2000 a linear foot.

    Basic monolithic glass for windows is available in 2mm, 2.2mm, 2.5mm 2.7mm, 3mm, 3.1mm, 3.2mm, 3.9mm, 4mm, 4.7mm, 4.9mm, 5mm, 5.7mm, 5.9mm, 6mm, 8mm, 10mm, 12mm, 15mm. and as well as other thicknesses. The specific thicknesses that I listed are ones that I have personally seen used in windows/doors, or other glass applications.

    Glass is also available in standard float (called plate by some folks, but that isn't actually correct), heat strengthened, tempered, and laminated.

    There are three primary laminated glass interlayer (plastics) available for use in standard windows - polyvinyl butyral (PVB), Sentry-Glas (SG or SGP), and poured liquid resins (several different versions). PVB is available in .015" (.38mm), .030" (.76mm), .045", .060", .090", and larger in .015" increments, since PVB is stackable in the interlayer sandwich. There are also a couple laminated glass products on the market that use a layer of PET film between two layers of PVB for added strength. SG or SGP is available in .030", .035", .060", .095" and .100", it is also stackable.

    ANY of the glass thicknesses that I listed can potentially be used in a laminated glass sandwich with ANY of the interlayers that I also listed, depending on application and whether or not the glass has been heat strengthened or tempered prior to lamination.

    Impact windows are manufactured using laminated glass. To pass TAS 201 large missile and/or ASTM E1996 missile D requirements (ASTM has 5 missile levels, A-E, Miami Dade TAS 201 has two, small missile and large missile), the interlayer has to be .090" or thicker. Glass can be as thin as 2.2mm (single strength), or as thick as specified by the application. Laminated glass intended for impact can be annealed, heat-strengthened, or tempered, depending on application. Since even single strength laminated glass will pass the 2x4 impact, choice of glass used in the lamination is based on ASTM E1300 pressure loading requirements. Use of thicker, heat strengthened, tempered glass is based on wind-load requirements - higher DP.

    PVB is soft and pliable, but also incredibly tough for it's thickness (as an aside, PVB laminated glass is required by ANSI Z26.1 (automotive glass requirements) to be used in ALL motor vehicle windshield applications)). When broken by an impact, PVB laminated glass will stretch to absorb the the force of the impact - be it a windshield or an impact window. The stretching characteristic of the laminated glass limits the force that goes to the sash/frame of the window caused by the the impact of the 2x4 hitting the window .

    This same characteristic is also why PVB is used extensively in blast-related safety glazing applications. The PVB will stretch and absorb the force of the blast wave, and since the broken glass adheres to the PVB interlayer, despite being broken and despite the force of the blast, anyone in the vicinity of the window will not be shredded by flying shards of razor sharp glass, which is the leading cause of death and injury in a building explosion.

    SG or SGP, much like polycarbonate or acrylic, is very rigid (5x tear strength and `100X the rigidity of PVB), and is used in larger windows or in applications requiring higher DP rating.

    Because of its rigidity when impacted, SG will transfer the force to the sash/frame components of the window system. This means that the sash/frame may have to be additionally strengthened or reinforced when using SG in the laminated glass window.

  • Lisa

    to the OP: Just get the windows already. Even if shutters provide comparable protection, most people do NOT want to start sorting through their garage or basement to find the shutters when a potential storm is predicted. Oh, that was a false alarm. Let's remove the shutters and put them back in the garage. Wait - the storm turned. Get the shutters! As we say, fuhgettaboutit!


    The impact windows will protect 24/7 even if you are not home. They provide UV protection, sound insulation, temperature control, and some burglary protection (mostly kids who would break your window).

  • oberon476

    More specific this time.....

    Laminated glass does not "shatter" in the sense of shards of glass flying around. I had previously mentioned that in my first post, that's why i wasn't sure what you were asking when you referred to it later.

    When broken, the glass adheres to the interlayer, although it does spall (as previously mentioned. I called spall "glass dust" in my earlier post, because that's what we have always called it when testing. Dust was the wrong word to use in that context here because it gives the wrong impression to people not familiar with spall....there is dust of course, but "sand" particles or tiny chips might be a better way to describe spall.

    In my previous post I talked a lot about multiple options for impact windows. Some impact windows are a single sheet of laminated glass glazed in the frame. This was very common years ago, whereas today dual pane is much more common with one lite laminated and one lite monolithic.

    The monolithic lite is often referred to as the sacrificial lite because it doesn't do anything to protect the building in the event the window is actually impacted. I am wondering if this is where your earlier comment on "sacrificial" windows may have come from?

    I much prefer the non-laminated lite to be the exterior in an IG window because I do want the glass outside if the window is broken, so i would look at that option if I was buying an impact window, but my primary concern if the non-laminated glass was inside would be clean up, not glass flying in the room if it was broken.

    I have never seen a DP rating of an impact window below 45psf, I have seen DP ratings over 100. Lower DP rating could be related to limit on water infiltration or it could be a lock limitation, or it could be the materials used in the window construction.....or it could be that this windows wasn't intended to be used in a HV wind-zone, something that is a consideration with windows.

    This is one of the things I was referring to in an earlier post when I compared shutter application to windows, but i wasn't clear on that. Impact windows do have different standards depending on where they are installed...and while very few companies have different standards based on potential location (no way that would be efficient, although some tried it early on), there are plenty of smaller companies who look to the market outside of the HV zones and they don't need to meet the higher wind-load requirements.

    A window with DP65 was tested to stop ALL water at roughly 62mph. This does not mean that at 63mph the window will leak like a sieve, it means that is the parameter that they were required to meet. The window could be watertight at much higher velocities than the protocol requires, but that won't be reflected in the window performance package.

    Another example, a window with DP85 would be tested to stop all water at a wind-speed of about 71.5mph...same conditions apply. They are allowed to test at a higher velocity, but they can't claim it. And while water penetration is tested at approximately 72mph, a DP85 is equivalent to about 185mph.

    A window with a DP100 is going to be fixed, not going to be an operator very often (in my experience). DP100 is equivalent to 200mph wind-speed. A window with DP100 was tested for water penetration at approx 77.5mph, and assuming no manufacturing flaws it is entirely possible that it will be unlikely to leak with increased velocity.

    And you might have already noticed that the increase in mph is not consistent with the increase in the design pressure? DP to mph comparison is not linear. As I mentioned earlier, the design pressure in psf calculates to the square of the ratios of the wind-speed in mph. Basically the mph isn't increasing equal to the DP , or as an example, in order to meet test parameters for rain driven by 150mph winds, the window would have to have a DP370 using the current parameters. While some window companies DO test for water penetration much higher than the protocol requires, that won't be reflected in the window design pressure.

    At one time test protocols did allow a different DP for structural and water penetration, unfortunately some companies took advantage of this loophole and only listed the higher of the two DP numbers for their windows in their literature. Since structural DP was usually higher than water penetration DP, the windows would potentially leak at even relatively low wind-driven rain velocity, possibly well below the listed DP. The requirement was changed some years back to eliminate the loophole so that the same DP was used for both structural and water penetration.

    Depending on window style, if the interlayer is intact after the impact (no tears or penetrations to a fixed or non-sliding (vertical or horizontal)window, then the window won't leak anymore than it did (or didn't) prior to the impact. The impact does not affect the window's ability to stop water penetration.

    Since patio doors, double and single hungs, and sliders are required to be impacted as well (some protocols, not all), then there is a risk of water penetration depending on damage to the meeting rail. Both TAS201 and ASTM require that the window/door operate normally (open/close, lock/unlock, etc) following impact so if there is significant damage to the meeting rail the unit is not likely to pass the test so potential for water penetration becomes a non-issue at that point.

  • PRO
    Evolution Hurricane Shutters, LLC

    Oberon,


    This is all very good information but from what you have stated:

    1. Impact windows that are touted as "shatter-resistant" or "shatter-proof" have no testing to determine the effectiveness of the claim - only a theory on how they are supposed to perform. I've seen the hurricane impact window laboratory test as well as many others in online videos. The theory is sound, but the reality differs.
    2. After all of the technical descriptions, DP figures and ratings and construction options, NONE of these water penetration tests are conducted AFTER the window has been impacted and only reflect the standards of a new, unbroken window.
    3. Water penetration resistance at 62mph winds is adequate for windows in many parts of the country but when hurricane winds are twice that speed, would you expect them to function at the same level if it was your house?
  • PRO
    Evolution Hurricane Shutters, LLC

    Lisa,


    Do the OP a favor and give him some facts. You are confusing storm shutters with storm panels. Hurricane storm panels require removal and storage - hurricane shutters do not.


    Accordion shutters, roll-down shutters and Bahama shutters are just 3 examples of the type that do not require removal, storage and re-installation. They do a great job of protecting any window - impact or non-impact. They also provide additional shade from the harsh Florida sun.


    Some research on your part would be a valuable asset in helping the OP or any other homeowner interested in protecting their windows instead of limiting their scope of options.

  • David Cary

    Anyone with a username with "hurricane shutters" in the name obviously has a financial interest in talking down the effect of impact windows. So you can post all you want but I personally would consider you to be a salesman talking about a competing product - in other words - I wouldn't believe a word you are saying.

    I would be more likely to believe someone names "Lisa" or "Oberon" so you might want to work on your marketing techniques.

    I think everyone understands what shutters are and how they differ from windows. How many folks are doing roll down exterior shutters to provide shade from sun?

    I would not get into a pissing contest with Oberon.

  • PRO
    Evolution Hurricane Shutters, LLC

    Unlike many who post one here, I have NEVER promoted any specific product or company on this site and never will. I didn't register with a name that would portray me as a "lurker" who hides behind a name but has an "agenda" to promote. THAT is the person who I wouldn't be interested in dealing with.


    If you think that Lisa "understands what shutters are and how they differ from windows", I don't how much more obviously blatant example I can point to.


    My intent is neither to sell a product nor get into a pissing contest with anyone. My only purpose is to offer options as they pertain to the subject - in other words, education. No one makes an intelligent decision without having the facts. Spewing a bunch of garbage information and making personal attacks do nothing to achieve that.


    Oberon is highly educated in the window industry and is a long time veteran. He and I both know that impact windows are good for many applications but also know that they have their shortcomings and that is the focus of my information. Unfortunately, the window industry in Florida is full of disingenuous folks who will deliberately mislead, misinform and fail to disclose aspects of their products that, I believe, can expose the general pubic to harm. If I didn't know for a fact that this was going on, I wouldn't waste my time discussing impact windows at all. I wish that Oberon was in Florida as a spokesperson to help combat the claims of those who aim to take advantage of the uneducated, scared and many times desperate homeowners who want to protect their homes, families and properties. I hear it on the phone daily and in person at EVERY event that I attend. Oberon knows this goes on and he doesn't enjoy it, either. That is one thing that we share.


    Whether you believe me or not, David, isn't going to prevent me from telling the truth to those who are looking for answers and options. If you have some knowledge to share, I encourage you to do so. I'm pretty sure that is what the OP is looking for - more knowledge to make an informed decision. Feel free to contribute. I'm always interested in learning something new, too.

  • oberon476

    Evolution,

    For what it's worth, I happen to really like your product concept which leads to a quick story....

    About 15 years ago (give or take a couple), a guy i was working with on a project asked me to help him out with an idea that he had about hurricane protection shutters.

    His thinking was that the major downside of shutters and plywood (pretty much 100% at the time) was that they covered the window making it impossible to see in or out. He had the idea of building shutters out of polycarbonate that wouldn't ever have to be removed from fixed windows, and when installed over any window wouldn't block the light or the view.

    My thinking was that he had a heck of a good idea and I offered encouragement and helped him with a few simple calculations and some minor proof of concept ideas.

    We lost contact not long after and I THINK he was contemplating moving to florida, but don't recall for certain.

    Anyway my point was that I had to wonder when I was looking at your website. Have to admit it made me wonder...

    To questions/comments....

    1) Nothing involving storm protection (or bullets, or bombs, etc) is proof. Resistant, yes, proof, no.

    Laminated glass is shatter-resistant, that's what it's for and there are required tests that exist to confirm.

    A dual pane impact window is with very few exceptions manufactured with one laminated lite and one non-laminated lite. As I mentioned previously, it's possible for the laminated lite to be mounted as interior or exterior, often depending on how the glass was glazed into the sash.

    If the laminated lite is inside and the window is broken by an impact then the loose (non laminated) broken glass WILL remain outside the building blocked by the laminated lite that isn't going to shatter. This is the make-up that I personally prefer and would generally recommend, and i have never been shy about telling people that here or real time.

    If the laminated lite is outside and it takes an impact that is powerful enough to break both windows, then breaking the inner non-laminated lite will result in broken glass inside the home.

    You have seen the hurricane impact on you tube, so have I, but I haven't seen a video of an impact that shows the glass shattering and flying into a room. In all seriousness I can't find one even though I looked for it. Can you drop a link, I am very curious to see it.

    I have personally performed, participated in, and/or witnessed impacts over 3000 times.

    I have also witnessed testing for impacts based on tornado level wind-speeds, but have never performed that test myself. The tornado test is a 12', 15#, 2x4 at 150fps.

    Interesting thing about the tornado testing was that over half of the impacts that I witnessed (and that was typical), the 2x4 shattered into kindling when it hit the glass and the glass was undamaged.

    I mentioned earlier that it is entirely possible to manufacture laminated glass that won't break when tested to TAS201 large missile and/or ASTM 1996, any level. I can think of three ways to do it as I type, and while I KNOW for a fact they all work because either I have personally been involved with manufacture and testing it or else coordinated with people who were, they aren't generally available outside of specialized applications.

    2} There is no requirement for testing a window for water penetration after impact, primarily because they are two different test requirements from two different agencies.

    The impact test is all about the product's resistance to penetration by the 2x4. The glass can break, but penetration of the glass isn't allowed.

    If the interlayer isn't torn then water can't penetrate it, broken glass or not.

    3) The requirement for water resistance testing is not related to or is part of the impact test protocol.

    As mentioned previously, windows are required to be tested for water penetration based on the DP level, and it makes zero difference whether the window is impact resistant or not, other than impact windows often have higher DP than non-impact windows.

    Although the requirement is based on the DP, this doesn't mean that's the maximum window performance. While I do know specific companies that do test higher than the DP requirement for their impact windows, I have no idea how many actually do so.

  • oberon476

    David,

    I hope that I didn't give the impression that this is a contest between us, that certainly wasn't my intent. I really do see this as a healthy exchange of ideas and information.

    And while it might seem surprising considering some of my earlier comments, I do believe that there are appropriate applications for both impact windows and shutters. I have even recommended shutters in the past where I thought they would be appropriate; but clearly I don't agree that people need shutters to protect their impact rated windows.

  • PRO
    Evolution Hurricane Shutters, LLC

    When I was introduced to this product, I had a palm-slap to the forehead moment. At the time I had been using, selling, machining and fabricating plastic sheet, rod and tube for over 20 years. The "Why didn't I think of that?" question haunted me for quite a while. Before moving to Florida, I was very familiar with exterior storm windows for saving energy in the winter. I often wondered why they weren't used to keep the summer heat out in Florida homes. I should have pursued it more intently.....just another coulda', woulda', shoulda'.


    I agree.....nothing is "-proof" - "resistant" is the universally accepted advertising term. I am not familiar with the testing for laminated glass. Can you give me the test method so that I can do some research in my spare time? I'm assuming that these tests were established long before the idea of using laminated glass for impact windows and an air cannon isn't involved.


    Back in the day I was employed by a glass company to perform tests on tempered and heat strengthened glass for glazing compliance. I wasn't involved in a laminated product. It's been so long ago that I forgot the ASTM designation of the test, but it's purpose was to assure that the size of the broken chunks were to the accepted size.


    All of the impact windows that I have seen are as you describe - tempered outboard, laminated inboard. The other way around makes very little sense to me. The laminated with PVB interlayer is the norm down here and thickness varies depending upon the approval rating desired. I've dabbled in some blast-resistant ideas, but the expense of testing and approvals vs. the ROI is prohibitive without having an "in" for government anti-terrorism or other opportunities.


    The water penetration test on totally intact windows makes sense for non-rated windows but what is the point if the windows are targeted for the hurricane resistant market?? If you want to stop ONLY wind damage, just say so and don't imply or infer that "your hurricane troubles are over"....if you simply install impact windows. All of the hurricane cyclic testing that I have witnessed is done so with a membrane because it is taken for granted that the window is going to leak air after it has been broken. I'm not a genius, but the gaps that I observed during the cyclic test were guaranteed to allow wind-driven rain to easily enter the structure. Sure, your roof doesn't blow off and the walls are still standing, but you could come home to water damages in the thousands of dollars. So many folks are under the impression that installing impact windows will be the "end-all" of their storm damage worries and returning home after the storm will just be a matter of picking up limbs out of the yard and the interior of their home will be untouched.


    Am I understanding you correctly that the water penetration resistance of a window is related to it's DP?


    So, water testing isn't part of the impact testing - but shouldn't it be?? Especially if you're asking the homeowner to flop down some big bucks??...And omitting the fact there still a very good chance that there will still be a chance of water damage if the winds are Category 2 or higher even without being impacted? It just seems a bit unfair to the homeowner, to me.



  • PRO
    Evolution Hurricane Shutters, LLC

    Oberon,


    Here's one video


  • K R

    Too much stuff here from pros. From my experience as a home owner, and having lived in Florida my whole life and through many hurricanes, absolutely 100% I would upgrade to impact windows. Shutters are a royal pain in the butt, whether they’re panels you put up, to ugly accordions you have to secure (still a pain and still have to get on a ladder to close some of them if they’re on the second floor) to roll downs on large windows. I have a combo of all 3, as my house was built in 2003 before they were doing impact glass as a standard upgrade. I recently replaced the sliders to impact, super duper expensive to do after the fact, to have to retrofit, and a pain with time and permits and inspections and all that. Next house I buy will have impact windows on all windows or I will not be buying it, end of story. Also with shutters you sit in the dark for days on end with an impending hurricane, also not fun!

  • PRO
    Evolution Hurricane Shutters, LLC

    K R,


    I agree. Storm panels are an absolute pain, but that is all that many can afford. Some folks still use plywood. The deployment, removal and storage of storm panels and plywood is definitely a hassle. The deployment is strenuous and can be dangerous in windy conditions - the panels are sharp and the plywood is heavy. Both can be caught by a gust of wind and turn into a sail.


    The introduction of the clear type corrugated panel has reduced the "dungeon affect" that the metal panels create. Some homeowners "mix and match" metal panels with plastic ones and some use 100% plastic.


    There are companies that also make a fabric and mesh type materials. Some are a translucent fabric and only let in light while others are more of a screen or mesh that you can see through. They are lightweight, easy to store and deploy. Some people use it to protect large lanais which creates a protected area to store your lawn furniture, ornaments and portable plants. It will even allow you to go outside during the storm. It's very popular for cigar smokers because it allows them an area to smoke outside of the house. This can also negate the need to upgrade sliders and windows that open to that area.


    Some accordion shutters and roll-down shutters now come with clear inserts, as well. Most new accordion shutters can be closed and secured from the inside if they are installed over operable windows.


    Yes, impact sliders are pricey and heavy. If the slider system isn't well engineered, there can be a lot of maintenance issues, too. Replacement is also expensive.


    There are lots of options available to protect both regular and impact windows from storm damage. It just takes some research to find out what works best for each homeowner.

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