Film to Glass Recommendations
This 30-minute webinar will guide you through reasons for thermal glass failures. Key conditions for you to understand the risks associated with glass breakage. What to look for to determine which films are most appropriate for your customers.
Webinar Flat Glass Evaluation - Film to Glass Recommendations - YouTube
https://www.youtube.com/watch?v=noBsizHZ_wo
Transcript:
(00:03) hi everybody I'm Jesse Manship the technical service engineer with matakohe and I'd like to welcome you to math goes April webinar series thank you so much for attending our online training Matic OHS technical service department is here to help support our dealers their customers and our medical sales team well for support on commercial solar and safety jobs answer two questions on a variety of topics from domes to glass a warranty energy analysis and film to glass compatibility further information is available on our website we also have
(00:40) monocles technical resources available at matok oh you from Anna co.com slash medical you or by following medical comm and clicking Monica you in the upper bar technical resources are just one part of medical you technical resources and film benefits glossary of terms and film packs in addition we have product training videos this is a list of some information on matica you a glossary of our solar optical properties tools some of which I'm going to discuss today installation instructions and tips and also
(01:15) frequently asked questions so today my goal is to give you a guideline on preventing glass failure filmed a glass recommendations glass and window construction basics the causes of glass breakage and seal failure the effects of installing film on glass basic kind blinds for preventing glass failures our film the glass recommendations and where to seek extra health so these are the types of glass I'm going to go over flat glass and neon heat strengthened tempered and chemically strengthened the float glass process is the most common
(01:56) method of flat glass production in the world this process basically involves melting silicate lime and soda into a furnace and floating it on to a large bed of molten tin hence the name flow glass this mixture slowly solidifies over the molten tin as it enters the annealing oven where it travels along rollers under a controlled cooling process from this point the glass emerges as one continuous ribbon and as then cut further and processed six it the customer's needs the major component of soda lime silicate glass is silicon
(02:28) dioxide which is simply sand other ingredients such as soum soda and lime are added to lower the melting temperature and to promote optical clarity the color and solar optical properties of clear glass can be altered in two ways first the glass can be tinted by adding small amounts of metal oxides to the existing ingredients for example the addition of iron oxide produces a green glass bronze and gray are produced by the addition of selenium and nickel oxide secondly a thin metal coating can be applied to the surface of
(03:02) clear or tinted glass this is known as coated or reflective glass the raw materials are mixed and then they enter the furnace once melted the material becomes molten around 2,800 degrees Fahrenheit glass and bubbles are removed and refinement and then cooled to control the viscosity liquid glass is then floated onto the molten tin around 1800 degrees Fahrenheit forming a ribbon since the glass is highly viscous it doesn't mix with the molten tin this produces a flat contact surface the thickness is controlled by
(03:33) increasing or decreasing the speed at which the glass spreads once leaving the tin the rigid ribbon passes through an annealing chamber where the temperature of the glass is lowered from 1050 degrees Fahrenheit to 480 degrees Fahrenheit further cooling takes place and then it's cut into sheets at the desired size the tempering process consists of several steps first the glass is cut the size by washing then heating the glass the glass is heated to a plastic state around 1,200 degrees Fahrenheit and then by computer control
(04:08) the glass is moved into a quenching area this is where it's rapidly cooled by a series of high pressure air nozzles the rapid cooling induces compression stress into the glass surface while the center remains in tension though the physical characteristics are unchanged the additional stress created within the grass increases its thermal and mechanical strength this is what's important to us after that the glass continues down the rollers to cool more and then be packed and shipped so what's the difference between tempered glass
(04:40) and heat strengthened glass the heat strengthening process is very similar to that of tempered glass but it's at a lower levels of surface compression compression resulting from a lower cooling quench he strengthened glass has a mechanical strength about twice that of annealed glass and if broken breaks into large pieces from edge from the edge and does not fracture into small fragments like tempered glass the breakage characteristics allow the glass to remain in the window frame as a large piece of support each other in the
(05:10) opening each strengthened glass also has high thermal strength like tempered glass and is resistant to thermal stress breakage associated with a high-performance tinted or reflected insulating units heat strengthened glass also provides resistance to thermal breakage caused by heat buildup in spandrel situations and the probability of nickel sulphide inclusion introducing spontaneous breakage is non-existent in he strengthened glass he strengthened glass is often used in laminated glass because it allows better
(05:42) inter layer adhesion than tempered glass due to the flatter nature of heat strengthen product the flatter finish also results in less optical distortion in the building facades has excellent breakage characteristics and prevents fallout as a result he strengthened glass is often used in curtain wall facades in both division and spandrel applications in some situations though heat strengthened glass is not suitable for example when safety glass is required for human impact safety for that you have to use tempered glass
(06:15) chemically strengthened glass is a type of glass that has increased glass strength as a result of post production chemical process when it's broken is still shatters into long pointed splendor similar to float glass for this reason it's not considered safety glass it must be laminated if its safety glass is required the chemical strengthening is by surface finishing Prophets glass is submerged in a bath containing potassium salt around 300 degrees Celsius which is about 3 572 degrees Fahrenheit this causes sodium ions in
(06:46) the glass surface to be replaced by potassium ions from the bath solution these potassium ions are larger than sodium ions and therefore a wedge into the gaps by this smaller left by the smaller sodium ions when they migrate this replacement of ions causes the surface of the glass to be in a state of compression and the core in a compensating tension chemically strengthened glass has little or no warp optical distortion or strain pattern this differs from tempered glass in which slender excuse me slender pieces
(07:20) can be significantly bowed also unlike tempered glass chemically strengthened glass can be cut after strengthening but it loses its added strength in the region about one inch from the cut similarly when chemically strengthened glass is deeply scratched this area loses its strength as well typical glass colors and coatings standard clear glass has an inherent clean green tinge which is more apparent when viewing the edge of the glass and stats this is due to the iron content in the silicon clear low iron glass contains approximately a quarter
(07:52) of the iron content of standard clear flow glass providing an extra clear glass that is crystal clear in appearance dented float is produced by adding metal oxides during the float glass production the most common colors are gray bronze green and blue apart from its function and aesthetics tinted glass is primary designed to reduce the solar heat gain UV and glare Tantive float glass achieves its performance by absorbing solar energy so sometimes it's referred to as heat absorbing glass this heat absorbing quality means the glass is
(08:23) thermally stressed so some thicker or darker products may need to be toughened to avoid thermal stress special coatings can be applied to the float glass to make it reflective the shortwave radiation that's the IR that you feel from the Sun or from long wave radiation that's the heat that's inside of a building these coatings go by a variety of terms one of the two main types are pyrolytic coating and this is a metal oxide coating applied online so during the glass production at high temperature
(08:54) this coating is fused into the glass surface make an extremely hard and durable it can be called online or hard coating a sputter coating is offline in special equipment this process deposits the medical part excusing metal particles onto the glass and a vacuum chamber almost any non-magnetic alloy can be sputtered the more common being stainless steel silver and titanium performance characteristics and Colour depend on the alloy and the coating density in general they have better solar control performance than pyrolytic
(09:32) coated glass traditional reflective glasses Amir like appearance and reflects and absorbs a major portion of the sun's correct shortwave radiation the degree of wrecked reflectivity is dependent on the type of the coating and the orientation of the glass the use of reflective glass is most popular and commercial glazings as it provides superior solar control performance to clear or tinted products low emissivity are traditionally clear and designed to reflect long wave radiation they are available in both pyro that the can
(10:05) sputter coatings in the performance varies some products have low e coatings to reflect long wave radiation as well as the sun's shortwave radiation sputtered coat and low E glass has transparent layers of silver and metal oxide sputtered onto the glass surface then metal oxides would surround the silver protect and suppress the visible reflectance of the silver pattern or obscured glass is manufactured many different thicknesses and has a variety of patterns patterns are usually not strength into a tempered due to the
(10:35) variation in the depth of the pattern etched glass has one side which had been treated with acid to use a grainy or satiny finish these are types of basic windows you can encounter in the field monolithic are typically of older homes or businesses consisting of a single pane of glass at a constant thickness the glass can be anneal heat strengthened or tempered laminated glass is bonded together multiple layers of glass typically with PV be usually laminated glass is two layers for the same thickness of glass and a single
(11:07) intimate inter layer holds broken glass together in the event of a breakage class can be annealed he shrank them too or tempered insulating glass is manufactured by enclosing a sealed gas between two or more paints of the glass the glass is separated by a spacer desiccants are added to absorb any water within the unit to prevent fogging filled with noble gases to improve insulation the glass can be annealed heat strengthened or tampered laminated glass is just like insulating except one or more of the panes is replaced with
(11:39) the laminated glass there are some benefits to having insulated units you have improved heat gain reduction and heat loss over monolithic glass they have solar and LOI coatings to lower the shading coefficient and solar heat gain coefficient space between the panes is filled with an over gas to lower the you factor some insulating units offer moderate UV blockage and they all offer an increased sound comfort over monolithic glass and using laminated a laminated pane will reduce the lowest the noise even more
(12:15) there are many types of windows and glazing systems the frames can be aluminum wood and vinyl aluminum window frames are light sean durable and easily extruded into complex shapes required for many windows use the most commonly found in the office settings non metal frames like wood vinyl and hybrid frames that use two or more materials the most common in homes wood is used because of its availability and ease of milling into complex shapes it's not the most durable because it's susceptible to rot vinyl is versatile plastic with the good
(12:46) insulation values and very low-maintenance hybrid systems like vinyl aluminum clad reduce exterior maintenance while still having the interior look and feel of wood dry glazing is the installation of glass using extruded gaskets in PVC or EPDM so one or both sides of the glass to provide a compressed weather seal no seal answer putties are used in this system and the windows are designed to be self-training and some low exposure conditions glazing tapes can also be used on the inside wet glazing is the installation using sealants and Beatle
(13:22) tapes to bed the glass and seal it to the framing silicone is the most commonly used but polyurethane and poly sulfite sealants are also used structural silicone glazing utilizes special grade silicone to adhere the glass and cladding materials to the aluminum aluminum sub frames so what happens when we apply from reflectance plus the absorption plus the transmission all equals 100% energy that's coming from the Sun so we commonly refer to this as the rat equation reflection absorption and transmittance higher the absorption with
(13:59) the less reflection and less transmission the hotter the glass will become leading to more thermal load on the glass edges and the surface this in turn will increase the thermal stress conditions so you ask yourself what causes glass to break thermal stress temperature fluctuation uneven solar absorption different temperatures throughout the glass and stress shading glass white interior shades and physicians thermal stress develops from differential expansion with an annealed glass caused by heating or cooling in a
(14:38) window the edge of the glass is shielded from the sunlight so the edge the covered edge will be cooler than the central area which is exposed to the Sun the expansion from the central area will cause the glass to stretch and yet be resisted by the cooler covered edges which will as a consequence develop tensile stress if this stretching of the edges becomes sufficiently large and the resulting tensile stress will be sufficient to break the glass we call this a thermal fracture when the tensile stress in the edge exceeds a
(15:11) critical point a crack will form the magnitude of this critical point depends on the strength of the glass edge a clean cut edge is the strongest as the cutting produces the least amount of damage a polished edge is the next strongest the actual edge strength depends on the quality of the glass edge so if there is no dam so if there is damage to the edge this will reduce the strength and increase the likelihood of a failure to your thermal fracture probability of breakage becomes significant with damaged edges
(15:48) the main thermal stress factors are glass type coating type and location heat traps which are blinds drapes or drop ceilings exterior shading heating and cooling vents and the framing system last type is one of the largest contributors to thermal stress the more the glass absorbs before the film is applied the higher the risk of a thermal fracture colored glass and high-performing glass absorbed more than clear glass of concern is low E and solar or reflective coatings just like films these coatings absorb reflect and
(16:29) transmit the energy from the Sun this is why it's important to know where the coating is located on the number-3 surface the coating is on the same pane of glass that our film is applied since the coating absorbs and the film absorbs coatings on the number-3 surface are more risk due to the higher absorption when the coating is on the second surface the risk is lower but for some of our products that are highly reflective this means we're reflecting the energy back through the outer pane that quarter that coating is absorbing
(17:02) some of that reflected energy as well he traps blinds and shades are are not excuse me when the interior shade devices are not properly vented or positioned heat traps can be established giving rise to high thermal stress they reflect the heat back in towards the glass they trap hot air in between the glass and the blinds it's dependent on the type and color of the device how much ventilation they have the spacing between the device and the glass at least two inches is required six or more is preferred for spacing drop
(17:38) ceilings can trap hot air in between the glass and the ceiling as well for exterior shading I'd like to emphasize that the outdoor shading is a dynamic design it varies seasonally due to changes in the incident angle of solar radiation in addition an important consideration is that shading and reflection patterns can be altered long after construction is completed with the addition of new or adjacent structures generally shading patterns with 50% or less coverage of the glass are most unfavorable because they cause the
(18:16) highest temperature gradients this is an example of thermal stress in glass it's important to understand the glass bite as you can see here the edges of the frame keep the perimeter of the glass cool in comparison to the center resulting in the most stress on the glass large fights increase the cool area and in turn the stress on the edge of the glass some examples of shadow conditions that can affect normal stress a linear shadow swing that straight up and down an angular shadow you can see it's a right
(18:55) angle there an l-shape shadow got two sides of the window that are blocked or a corner shadow this is an example of just a linear shadow and you can see the stress extends much greater than when we had just the edges the frame in which the glass is captured affects the temperature of the edge of the glass thermal stress will be increased as the thickness of the metal increases metal framing systems that have included a thermal barrier reduced the thermal stress on the indoor glass of the insulating unit passive concrete
(19:34) or metal frames in thermal contact with the glazing rebates have a great heat capacity and will result in increased thermal stress in the glass when the concrete or metal becomes cold and does not warm up as fast as a central area of the glass unit when exposed to the Sun heating and cooling events that blow air against the glass can form hot or cool spots on the glass it's just like a shadow desk these are some risks when applying film monolithic glass that's thicker than three-eighths of an inch this is over two times more absorbing
(20:07) than 1h 1/8 inch thick glass 18% vs. 8% tinted monolithic glass can be up to 90% absorbing this would be very dark by the way a 50% VLT blue glass for example would have an absorption around 60% laminated glass maduk only recommends one film applied to laminated glass our Nova 70 we don't recommend using other films since the film can absorb too much energy and this can lead to a crack or delamination of the laminated glass insulating units have their own risks ones that are greater than 40 square feet they have tinted glass triple pane units
(20:44) and certain low e configurations the best case is if the window were the laminated glass this made from heat treated or tempered glass he treated glasses and it'll able to absorb a tremendous amount of energy without the risk of a thermal fracture conditioners that cause insulating glass failures an IG u seal can fail when the desiccant used to keep the space dry no longer absorbs moisture that migrates this can happen because of natural aging or because of unsatisfactory design that allows moisture to become trapped near
(21:16) the edges of the IGA other issues can be Skip's or voids in the sealant incompatible glazing materials with the sealant adhesion of the sealant to the glass could fail elevation changes without proper ventilation so natural aging temperature pressure humidity and UV exposure you can test for seal failure by using a frost point tester this device lowers the temperature of the glass which allows any moisture which that's within the itu to condensate on the glass you don't need a frost point tester though ice
(21:52) will do hold the ice to the surface of the glass for a couple minutes to lower the surface temperature of the glass if you notice that there's internal haziness with inside the unit then they'll see that haziness when the weather gets cooler film should not be applied to windows that have existing seal failure so when you're on the jobsite what do you want to review the glass fight how much is it thermal isolation examine the gasket and the sealants to ensure that they are resilient and will allow for thermal expansion what's the
(22:24) condition of the framing system is it old and is it damaged drapes blind shades are they ventilated do they allow the heat to escape heating and cooling events are they pointing towards the windows exterior shading look for trees homes buildings imagine the position at different times in the day will shadows form on the window and for the weak functionality look for clogs it'll cause rainwater to accumulate in the frames tools to bring a dew point frost testing device also look for failed seals don't
(22:55) don't require using this method ask if they had to replace windows in the past glass thickness air space gauge this is a must for measuring the glass and air space thickness toughened glass meter another great tool for identifying key strength and glass a low ee detector perfect for identifying the location of the low e coating sit on the number two or the number three surface a tape measure a camera product reference sheets and evaluation sheets and summary sheets to record your data has three-film the glass charts to
(23:28) assist you in choosing the correct film for the glass and windows that you encounter the chart has the film's to the left and then along the top the various glass configurations a proof window films show a green check films that require a film to glass application are indicated with an orange circle in films that are not approved or shown with the red X these are available digitally and then they're also printed too so in conclusion most films may be used for most applications when using the film the glass recommendation charts
(23:57) make sure that your installation is approved when in doubt contact technical services and we're here to help you so we have some upcoming webinars that we'd like to let you know about before we finish up on April 16th we're going to talk about shop Matic Oh calm and then on April 27th we're going to go over some types of glass meters and how to use them and on April 29th we're going to be doing a clear Plex installation training and I'll wrap up the training for today you may have some
(24:29) questions I saw a bunch of flashes going on as I thought thanks Jesse it doesn't look like we have any questions right now but I don't know how zoning equals just yeah people were entering information in the chat box but I just want to give everybody just a minute if they do have questions to enter them find your chat box and enter any questions into chat we do have about four minutes left if anybody wants to ask a question we have a technical expert here that can answer them oh we do have a question outside the United
(25:10) States we see a lot of reference to heat toughened glass what does that mean so I'll go back up when we're talking about sorry if the chats in the way guys sorry I'm learned I'm new to this thing called computer here so when we're talking about temper versus heat strengthened and then so tempered it overseas is commonly referred to as toughened and it's just a a different word for the way that they call things so when we were talking about tempered it's also referred to as toughened
(25:53) overseas okay and then another question came up I ran into bullet-resistant glass at a bank can you install film on that really dependent upon what they're trying to do so if it's bullet resistant glass and it's blocking the teller and it's not going to receive any solar exposure you can install film on there but you have to be careful because you want to make sure that the surface that you're applying to is actually glass sometimes they use polycarbonate or a different surface on the outside to control
(26:34) spalling and you may not be able to apply film to it if it's not glass if it's a window that's facing the exterior of the building you need to be very careful about installing film on it because it's a thick laminated piece of glass and you have to be very specific with them on what you're trying to do I'd recommend that she contact us first before you even film anything that's bullet resistant because the last thing you want to do is accidentally cause any damage to that very expensive glass or
(27:01) the worst case would be if it's cracked and then they have to shut down that section of the bank to protect their employees they could get very upset at you Jesse another question just came in why do tempered units appear to have two different surfaces one is always more gritty than the other side so when they make glass and it's floating on on the tin where I should just make sure you're drawing here one surface of the glasses has is exposed to the air and the other surface is on the tin the side that's
(27:40) exposed to the air you can imagine gets little pieces of dust and things in it and so when it gets quenched at the end after the after they cut it one side is a little bit smoother than the other and so that's why you notice it most of the time the Glazers are supposed to install that gritty side towards the inside every once in a while they do it backwards and that's when you notice it when you run your knife over it and you're going and you go hopes and then you have to clean it with the white
(28:08) scrubby instead okay and then one last question Jesse somebody asked how can I know when a windows tempered most times it has a stamp that says it and it makes it easy to know but sometimes there's no stamp sometimes the stamp is hidden or it's up at the top there are tools and I have another class that's coming up but if you use this strength and glass detector it's very very accurate at determining if the glass is tempered or heat toughened as they referred to overseas what you're looking for with these
(28:49) detectors is the string patterns within the glass so if you've ever worn polarized glasses and you notice how like the back windows or the side witness of cars they look checkered or they have the weird pattern to them that's what this device can can see and let you see it from the inside without having to wear sunglasses and view it from the outside great thank you so much Jesse and thank you everyone for attending this will end our webinar thank you everybody
