Is acoustic glass worth it. Good for skylights and roof glazing.

Is acoustic glass worth it The primary benefit of acoustic glass is its effectiveness in reducing sound transmission. Yes, I suppose it is a little quieter than a single pane of tempered glass. Thirdly, use experienced professionals. The effect of the laminate is to disrupt the soundwaves and to help Is acoustic glass worth the extra expense? Is it noticeably different from normal double-glazing? We live on a busy main road and currently have single glazing with wooden frames plus aluminium- framed secondary double glazing. The soundproof membrane inside the glass reduces sound by absorbing the sound wa What is acoustic glass? In general, the thicker or heavier the glass, the greater the noise reduction. I’ve looked at why the highlander deals with wind noise so much better and one of the reasons are the acoustic glass. For example, acoustic windshields can also help to reduce heat loss, vibration level, and air resistance. They block up to 75% of low-pitched noise (traffic, air-conditioning compressors, etc. surrounding traffic. Ambient noise, such as that coming from a nearby road or busy shopping area, can be disruptive to your daily life and if it is also taking place at night it can lead to disturbed Acoustic Glass Defined. FAQ: What Is Acoustic Windshield & Is It Worth It. The acoustic windshield also called acoustic glass is made with a mixture of raw glass and sound damping materials. Softer volume levels can be used to play music. Have you ever wondered what Acoustic Glass is, and what effect it has on cabin noise? Tim & Jill wondered the same thing, and in this video, they break out t Is Acoustic Glass In A Car Worth It? Credit: www. It is made by sandwiching a The Many Benefits of Acoustic Windshields Noise Reduction. A4 (B9 Platform) Discussion - US A4 Prestige Acoustic Windows - I've been browsing the forum for a long time and was finally convinced to jump in with an order for a new A4 or Allroad but ran into some conflicting information regarding acoustic glass. Acoustic windshields have an acoustic film between the two parts of plastic. You’re probably wondering what the difference is between this glass windshield and a standard one. 4mm clear /18/ 6. So has anyone installed acoustic glass to their car and if they did how much did it cost? Any response is appreciated The reason: The 33 dB windshield is made of two layers of glass with an air space between, while the 27 dB model has only one layer of glass and no air space. What is the optimal choice is the best value IGU component combination that is capable of meeting the noise reduction needs of a room. Plus the other cars you've mentioned. In addition, the extra layer of film makes the glass more Acoustic glass, commonly referred to as soundproof glass or noise reduction glass, is a specialized type of glass designed to significantly reduce noise transmission through windows and doors. Acoustic glass is made especially to reduce noise pollution, whereas triple glazing is an improvement of double glazing. The result is improved adhesion between layers and less vibration Acoustic side glass is laminated to reduce sound transmission. The PVB interlayer in laminated glass effectively dampens sound vibrations A secondary effect is that the acoustic glass weighs a little less than the standard offering. 2x1. This results in a quiet and serene indoor environment, which can improve comfort, productivity, and focus. Acoustic glass vs double glazing . Avoid these products. Both types of windows have been made for a different reason. Bullet-proof For example, the acoustic glass partition systems we offer here at Glass Interiors can reduce sound up to 32dB – 57dB, depending on the type and thickness. Acoustic Glass. An acoustic windshield is meant to block external noise from the front i. The thicker the glass, the better the sound insulation properties. What is acoustic glazing? Acoustic glazing is a window comprised of two or more panes of glass, often of different thicknesses, with a layer of laminate or acoustic foam and air gaps filled with an inert gas Acoustic glass works differently to triple glazing. Both equally loud imo & noisy engine droning sound compared to my Volvo/acuras. Acoustic glass consists of two or more sheets of glass, bonded together with one or more acoustic interlayers: Each pane of glass in a noise reduction window or door is laminated with a layer of polyvinyl butyral (PVB), forming a strong hydrocarbon bond with the glazing unit, this improves acoustic attenuation by reducing the elasticity of the glass and Acoustic glass can be double or triple-glazed, but for comparison, we will look at double-glazed acoustic glass v triple-glazed windows. I am going to sound proof my doors and B pillars and maybe the back wheel wells - I hear that makes a massive difference. The window is 1. 5, and can confirm that on my car there is zero wind noise at any speed up to the 128mph limiter. Acoustic glass reduces motorway noise by 20%, reducing noise levels by 80 dB. 4mm would make a noticeable difference over 6. Acoustic glass is double or sometimes triple-glazed. A. To test it, get a noise meter and park each in turn in the same spot facing a busy freeway. Tire noise is most noticeable on the stock 20" P Zeros It may be more expensive than triple glazing, but all of the described benefits make acoustic glass worth the investment. 2016 Pilot Touring and Elite get acoustic front door glass. Impact: It reduces the noise level by up to 3 dB, which means, in psychological perception, the noise from the outside is cut by about half, allowing a Acoustic glass windshields just make for a more comfortable journey, even if the normal person doesn’t need to communicate properly in their car in an emergency. Acoustic glass is better used in double glazed units where the 2nd piece is a different thickness to the 1st piece Eg. Whether it’s for an RV, SUV, commercial vehicle such as an agricultural combine, or for an emergency vehicle such as a firetruck or ambulance, an acoustic glass I don’t know if any manufacturers make door or rear window acoustic glass. 4 lam. However, the degree of noise reduction depends on various factors such as the thickness of the glass panes Still very good though for an A4 and worth adding on for an extra few 100 quid. Is acoustic glass worth the money? Not only is acoustic glass ideal for noise reduction, but it also increases the strength of your glass, making it much more secure than your standard glass. Thick glass. Most of the big nationals use the cheapest profile on the market yet sell it for a huge mark up. mmmzon. Acoustic glass is a highly versatile material that comes in different options such as acoustic glass, double glazing glass, tempered glass, laminated glass, etc. Laminated Glass Is More Efficient Than Acoustic Grade Glass . While the main purpose of an acoustic windshield is to reduce the level of noise experienced inside the vehicle, they also help with improving overall comfort while driving. damn. 8mm and a dB rating of between 35 and 42. But if you’re a town or city dweller and your peace and quiet is being disrupted by traffic or general street noise, acoustic glass is an Acoustic glass is a special form of laminated glass designed to reduce the amount of noise that can travel through it. The engine is gonna drone - Atkinson cycle with less firewall soundproofing. There is a lit less sound insulation on these due to weight shaving. Types of Acoustic Glass Laminated Acoustic glass not only controls the sounds travelling from the outdoors to the indoors but also reduces the sounds travelling from inside to the outside ensuring privacy. Have you had it before? It adds a level of refinement and isolation to the vehicle, but fair warning— it won’t make things silent. If adding privacy, comfort and peace is at the top of your project's priority list, our glass is a great route to get exactly what your property needs. A significant purpose of an acoustic windshield is to improve a vehicle’s acoustics, hence the name. Triple glazing has three panes of glass with airspace in Laminated glass retrofit totally worth it for my 2020 Model Y . Acoustic glass known as laminar acoustic glass, which is laminating two pieces of glass together to form a polyvinyl butyral (PVB) membrane, is a type of glass. Obviously it won't be a single piece of glass but rather multiple small ones just like in most windows. 2393 posts · Joined 2020 Add to quote; Only show this user #5 Compared to conventional windshields with two panes of glass and an in-between layer of plastic, acoustic auto glass has one more acoustic layer. But it is true that you might want a different version of acoustic glass depending on the frequency profile you are dealing with. Joined Jan 12, 2005 Messages 4,352 Location FL. So I'm just trying to know if the extra money I need to spend for the thicker one will be worth it Reducing bass would be awesome so maybe I'll go with the 1/4. Acoustic glass, also known as soundproof glass or noise-reducing glass, is specifically designed to minimise noise transmission from outside into the interior of a building. Doesn't hurt from a safety perspective. How much difference does acoustic glass make? Its thermal properties are much better compared to single-glazed windows. My Jeep Wrangler has an acoustic glass windshield from the factory. There are several different types of acoustic glass available, each with its own unique properties and benefits: Laminated glass: This is the most common type of acoustic glass. Acoustic glass protects our hearing and prevents any subsequent problems. It is better at reducing noise and keeping energy bills down for your home. For this reason, acoustic glass is also Proper Acoustic glass can greatly reduce noise, but consists of varying glass thicknesses laminated together, with a thick layer in-between the glass, not simply applied to one side of a single pane of glass. I thought it was a lot quieter than the 2005 Odyssey I'm looking to replace with a Pilot. A thin layer of glass can’t block out nearly as much sound as a brick wall or a roof. How much quieter is acoustic glass? I've just got an 2020 A5, it doesn't have the acoustic reducing glass but it's extremely silent compared to other cars I've driven (audis, an r8 or a maserati levante with dual pane glass) One car I'm pretty sure has acoustic glass is the A6. Acoustic glass – is it worth it? Aug 27 2019. With acoustic laminated glass, the drop in the noise levels inside your car is The acoustic glass is included with the prestige package only for the C7. They'll block heat on top and is worth it than just having regular dye that has metal, which also can interfere with GPS and radar detectors, more so if you were The Ltd's with "acoustic glass" came in at 65-66 dB, and the XLEs came in at 65-66 dB. It’s a type of laminated glass that includes a layer of acoustically-insulated layer to absorb sound waves and reduce noise transmission. Acoustic Glass: Due to its multi-layered construction and specialised interlayers, acoustic glass is typically more expensive than both standard and tempered glass. Besides, all my cars had moonroofs which I never opened anyway. cuke2u Registered User. Lets find out together! If you want to collab or When it comes to a windshield, there’s a lot more than meets the eye—or ear. However, the significant noise reduction it offers can be valuable for Unsurprisingly, the best option for reducing noise is acoustic glass. The price you would pay for acoustic glass would be about the same as triple glazing. PVB is an acoustic membrane which bonds the two panes of glass together to give the appearance of a single pane of glass. an additional 60% more than its counterpart. If you live in an area that has lots of noise the thought of acoustic glass may have crossed your mind more than once. That usually fills between both laminate regular films. Therefore, sound reduction efficiency increases as glass thickness increases. As with all of these missing parts, I’d much rather have the part than whatever measly credit Audi is giving for it. Wrangler windshields get chipped and cracked all the time. Heck I remember my old trailblazer ss had that glass on The higher the STC rating, the better the soundproofing. Acoustic glass also improves the strength and durability of the window area, making it harder to crack or break in. This is achieved through a combination of features: Thicker glass: Compared to standard 3mm-5mm glass, it typically boast thicker panes, often laminated with a damping film The careful and considered selection of glass can be crucial in helping to reduce noise level and meet noise requirements. don't get me wrong the cars quiet and does a great job of blocking out most wind noise but Declaring laminated glass to be "acoustic glass" is just pointing out a secondary characteristic. Instead of the PVB interlayer, acoustic glass contains a special resin as an interlayer in between two sheets of glass. It’s bonded together using a special resin, giving two panes of glass the appearance of one single pane. Is It Worth Upgrading To Triple Pane Windows? The addition of a third glass pane improves efficiency and reduces noise, making triple-paned windows more efficient overall. e. Joined Sep 14, 2013 Mine has acoustic glass and personally I think it wouldn't make that much of a difference without it. It has a good rundown of factors to consider when choosing acoustic glass, so it’s worth checking out. The LE, XLE and XSE do not. If you are looking for a way to reduce the amount of noise that comes into your car, then acoustic glass may be worth the investment. Does triple glazing reduce noise? Yes, triple glazing can reduce noise as it adds an extra layer of insulation. When selecting a The word “acoustic” or the letter “A” in the lower portion of the windshield will ensure you get the best acoustic glass. The way this glass is formed is by taking two pieces of thin glass and bonding them together by a piece of plastic. The ambient noise is less distracting. Installing acoustic glass can increase the value of your property. That's a big difference from the $850 the dealer asked for. Acoustic glass is worth way more than $500. It's also ideal for spaces that require sound containment In general, a single acoustic glass break detector can cover a number of windows and glass doors in a room, depending on its size; it does not necessarily need to be installed every window on the ground floor. Whether it’s worth walking away from the car is debatable. Acoustic glass helps reduce wind noise in Odyssey models. There are both oem and aftermarket acoustic glasses available, however if your car or a higher trim version didn’t ship with it you’re not going to find it in aftermarket. I waited for it on my recent vehicle order because I absolutely Is acoustic glass in a car worth it? If you want a quieter ride, then you’ll reap the benefits of acoustic glass. And finally, the glass composition: the glass is an important factor in soundproofing windows, as it usually makes up around 80 percent of a window’s area. The best acoustic windshield models include those with multiple layers of glass and some sort of air space in between, whether it’s a foam core or a small piece of plastic. I have had loaners without the acoustic glass and both my wife and I think there is a noticeable difference between the two. Also, our team of highly trained technicians can take care of all your windshield repair requirements and provide you with the best results. For me it is an option I will get again so it is worth it, to others they may not feel it is because the X5 without it is pretty quiet without it. Only the upper two trims have acoustic glass. A subreddit for all things related to the Ford Mustang Mach-E. The glass used in acoustic windshields is thinner than the layers you can find in regular screens by about 5 millimeters. Laminated Acoustic Windshield; The reason why this type of windshield is lighter is that the sheets of glass are thinner by about 5mm or 4mm. Is acoustic glass worth it? If you live in a quiet country area, away from main roads and with little traffic noise, regular double glazing will probably be sufficient to keep out any extraneous noise. Acoustic glass is a little different than laminated glass. The actual level of sound reduction may be affected by certain factors such as Acoustic Glass Thickness. (acoustic) glass Tesla started using for the driver and passenger windows in 2021 and the conclusions were mostly that it made little to no difference in vehicle noise. asiancivicmaniac. Here are 2 pictures, for what it's worth Reply reply In addition to its noise-reducing properties, acoustic glass is also stronger than standard glass. As a result, you are better able to concentrate on the road or your current task. Acoustic glass can reduce the amount of UV radiation entering the space by around 99% – a reduction of 320 to 380 nanometres. The frugal side of me would rather pay for an EX model; however, there isn't an EX here in Portland, Oregon to test drive. Acoustic sensors can detect breaking glass using microphones, which means a single sensor properly placed in a room Welcome to the "IS IT WORTH IT" channel! If you are here, you are probably looking for a certain product and want to know if its worth it or not. ) and up to 95% of high-pitched noise (bus I'm going to assume the glass will be like windshield glass where you have 2 layers of glass with plastic sheet in between. As you can see, acoustic glass has a lot of benefits. That said, there’ll be The Limited and Platinum trims of the Sienna have the “acoustic” laminated driver and passenger side glass while the XSE has tempered driver and passenger side glass. Installers tend to be bias to what they install. It may be more expensive than triple glazing, but all of the described benefits make acoustic glass worth the investment. My Fiesta is relatively Acoustic glass is something the manufacturer calls for on specific makes and models of car. 8 Laminated I'm not a specialist in this area but I can't see how a sheet thicker by 0. Bearing in mind that a reduction of 10 dB will halve the perceived sound intensity, the thickest acoustic glass is highly effective but also only really necessary in the most extreme cases such as building near an airport runway. While they look like ordinary clear glass panels from the outside, acoustic glass panels are made by bonding at least two sheets of glass together with an insulating layer in between Acoustic glass is two layers of glass laminated with a plastic layer in between. 8m. The Chevrolet Impala is available with acoustic glass for the windshield and the front side windows; as are some high-end Infiniti models. Sep 21, 2016 #14 Ford seems to be putting it on all the windshields of their new cars. But sticking Perspex right on to the glass flat with no gap would not be worth it IMO. Is acoustic glass worth cost upgrade from EX to EXL? Click to The acoustic glass is worth it, especially if you like listening to entertainment of any sort - the thermal performance of the car I wouldn’t expect to change whatsoever . In roofing, these glazed units will improve insulation and provide noise reduction from rainfall. Probably worth the money although, like you, I've gotten tired of leather seating. the installation: If the windows are not well sealed, noise will find a way through, along with cold or heat. The PVB membrane between layers of windshield glass absorbs sound waves from the outside world, reducing the amount of sound that enters a car. The layers make the glass more resistant to breaking and help to hold the shards in place if the glass does break. The latter factor acts as a sound screen windshield, reducing external noise entering the cabin and allowing passengers a noise-free and much more comfortable journey. The highest noise insulation is achieved using an acoustic laminated glass. Acoustic glass typically has an STC rating of 35-40, compared to standard glass which usually has an STC rating of 27-30. org. Good for skylights and roof glazing. Acoustic glass, the best performing and often, the most expensive option, is not necessarily the most ideal type of glass for a specific space. When we apply a layer of lamination to our glass, it makes the pane more rigid and reduces vibrations. You can get even thicker glass, Before delving into the pros and cons, let’s clarify exactly how acoustic windows work. Enhanced thermal insulation helps maintain a consistent indoor temperature making the space more comfortable. Vacuum glass acts as an effective sound barrier, blocking external noise and creating a quieter indoor space. Benefits of Acoustic Windshield Glass. It reduces noise levels by 70% as well as noise levels by 80% for a dog. Laminated glass is the next best option after secondary glazing to reduce noise but is usually more effective at reducing high frequencies such as aircraft noise. There are also different thicknesses of glass available. Protects Driver Hearing – Speaking Yesterday I test drove an EXL which comes with acoustic glass. One of the most widespread uses of glass is in making windows. If your main motivating factor was to cut out the drone of heavy traffic outside, then acoustic glass will work well and cut out a significant proportion of the sound and life will be quieter. Enhanced Acoustic Performance Noise pollution is a common issue in urban environments. Does triple glazing reduce noise? Technology: Acoustic windshields use an interlayer of special acoustic polyvinyl butyral (PVB) designed to dampen sound waves. A thicker interlayer than what is commonly used can also benefit acoustic control. Thanks to this combination, the acoustic glass absorbs the sound vibrations I spoke to an auto glass repair shop guy and he told me that he could replace the windshield with acoustic glass for $300. The only downside is the wait. Only thing I think I miss is the 360 parking, but I’ll live not worth $7-8k more. The construction of the window frame and installation is important too. In this article, we will explore both acoustic glass and triple glazing, highlighting their features, advantages, and drawbacks. This is why vacuum double-glazing is a popular choice among those in listed buildings, as it’s thin and discrete enough to ensure that a property doesn’t lose its historic Laminated glass. Different glasses are used What is Acoustic Glass? Acoustic glass is a laminated glass developed for effective sound insulation in environments having high noise levels. Save Share Reply Quote Like. We had one Honda salesman tell us that acoustic glass was 11 layers thick, and normal Honda windshields are 7 layers thick. When shopping around for a I have a 2018 highlander platinum and also a 2020 Range Rover and these handle wind noise so much better. Often using laminated glass for high performance acoustic double It will be a single glass layer window. Factsheet - What is Acoustic Glass? Acoustic glass consists of two panes of glass which have been laminated together using PVB (Polyvinyl Butyral). It will break easier but not fall apart like tempered glass would. EX-L and up get acoustic windshield glass. That might not sound like much – considering acoustic glass can block out as much as 45 dB – but that is the equivalent of rustling dry leaves in a silent library or heavy rain heard through an open window. The difference between acoustic glass and double glazing is approximately seven decibels. I have an early production 2020 Model Y that, while an overall great vehicle, was too. What is the difference between glass and acoustic glass? It’s all in the lamination. How it works As far as telling the difference, acoustic glass is more effective against high frequency noise. I see acoustic glass for the windshield and two front windows in Is acoustic glass worth it? I am still undecided. I decided On the other hand, acoustic windshields comprise of two layers of much thinner glass that are sandwiching one layer of acoustic vinyl in between. Odyssey EX-L and Has anyone found information in a pamphlet or on a website from Honda about what exactly "Acoustic Glass" is? I have looked on the web and at the 2011 Odyssey brochure, and I cannot find where it is defined or explained. Acoustic glazing is used in windows, doors and partitions to Acoustic glass, also known as soundproof glass, or noise reduction glass is specialist glass installed in noise reduction windows that can reduce the amount of noise that is transmitted through the glass and a window (or door). As for which profile is best. 8mm to 16. Glass controls noise by: Reflecting the noise back towards the source, and ; Absorbing the noise energy within the glass. Gorilla Glass makes windshields for But the acoustic glass that we use is the most important of the noise reduction materials that deliver the soundproofing qualities of our windows. It is worth taking some time at this point to work out your expectations about what life will be like after installation of acoustic glass. However, this acoustic windshield looks the same as the regular one. 5 mm to 12mm thick. Last edited: Jan 4, 2017. This way of assembling glass reduces the amount of noise that can vibrate through it, Acoustic auto glass is similar to automotive safety glass, but it has a layer of acoustic (PVB) vinyl sandwiched between two layers of standard PVB and safety glass. The layer is thicker than in standard windshields, effectively blocking multiples of frequencies of noise. Tuned specifically to cut wind-noise frequencies, it uses two layers of safety glass with an inside layer of a transparent and elastic acoustic membrane. . The best way to detect an intrusion is with a motion detector, whereas the window sensor is better at detecting actual intrusions. benzworld. My question is, how would I be able to tell the difference from regular single layer glass? He mentioned that there would be code on the glass that has an A for It is better at reducing noise and keeping energy bills down for your home. loud. Its unique structure helps to attenuate sound waves, making it ideal for commercial buildings, residential apartments, and even greenhouses where peace and quiet are essential. Does Acoustic Glass Work? Our acoustic grade window inserts reduce sound an average of 85%. Unlike regular windows, they’re designed to act as a barrier to sound waves. Is acoustic glass in a car worth it? If you want a quieter ride, then you’ll reap the benefits of acoustic glass. Protects Driver Hearing – Speaking of a quieter ride acoustic glass windshields reduce such a significant amount of noise that it can protect against driver hearing loss. One XLE, which we bought, hit 64 several times and was subjectively quieter than the Ltds. Types of Acoustic Glass. Like laminated glass, it looks just like a normal pane of glass – you won’t notice the ‘sandwich Thicknesses of acoustic glass can range from 6. This glass is produced by applying heat and pressure to glass plates and a sound-absorbing PVB (Polyvinyl Butyral) interlayer. It has acoustic glass on the front side windows (not sure about windshield). It is important to note, however, that acoustic Love the acoustic glass myself, in part because it’s not just helping with sound, it helps insulate temps too. It is this vinyl layer that is responsible for noise absorption. One-time fixes like noise complaints might work for loud block parties or for the aspiring musician living on the floor above you, but you can’t file a noise complaint against an airport, garbage truck, or Is acoustic windshield worth it? Compared to ordinary 5mm glass, acoustic glass reduces noise by up to 90%, i. It helps to reduce external noises such as traffic, construction, and street sounds, while also minimizing internal noise within a building. With such glass, you can drive comfortably. Getting all the information related to the Acoustic glass windshields are an excellent choice for people who spend a lot of time on the road, especially in areas with lots of construction, like near an airport. Normal vs laminated vs acoustic glass. Secondly. In the case of the Panamera, the reduction in weight is around two kilograms. As a result, acoustic glass is a safer choice for homes and businesses. Is acoustic glass worth it? For areas where noise levels are high, such as near busy roads, this type of glass is worth the investment. It’s an option like a rain sensor location or the film for a heads up display. Usually, glass will be between 6. It fits my lifestyle perfectly because I like to feel airy with a lit cabin but not too sunny. Acoustic windshield glass is majorly beneficial when it comes to the safety and comfort of your driving experience. Acoustic glass laminated to prevent 99% of UV light transmission can also protect against harmful sun rays. How it works. Dynamic Sky Glass Roof worth it? But on the Dynamic Sky and when frosting the glass there is a noticeable amount of light reduced to the point where it feels like there is a sunshade. Sound moves in waves, and the greater the power of the wave, the louder the noise will be and the further it will travel. Acoustic glass, as the name suggests, is designed to reduce the noise emitted Although it’s always worth asking, it’s unlikely that permission will be granted for acoustic glass to be installed in Grade 2 listed property due to how thick it is. Acoustic glass is a double glazed unit that includes a pane of laminated glass. But with out the heat loss benefits and probably less of a reduction in noise. 3. This type of glass helps to block out some of the external noise, making for a more peaceful ride. With a different aim comes a different functionality. This innovative material is integral Range Rover and BMW use lighter acoustic glass. We are getting UPVC double glazing to replace the wooden framed single-glazing but keeping the secondary double glazing. My question is, could I take the van to a reputable auto glass shop and have the driver and passenger side tempered glass switched out to the OEM acoustic glass from the Acoustic sensors use built-in microphones to detect the sound of breaking glass. They are ideal for studios, home theatres, or locations with extreme noise 16K subscribers in the MachE community. Soundproof Windows (Acoustic Glass): These specialised windows utilize a combination of strategies like laminated glass, thicker panes of dissimilar glass thicknesses, or special gas fillings in the air gaps to achieve the highest level of noise reduction possible. hzblxb ugrmorfl dhqx opjags fwaea pykcpcc jsblip hjwvo queg adqf jzwzy gom kqu irruku tzkpw