Tempered glass will be the best option if you want a glass insert that is less likely to break when impacted by something like a baseball or a thrown 2x4.
But, when tempered glass breaks – and it will if given enough force - it does end up as a pile of little glass pieces all over the floor - leaving the opening - open. Tempered glass is actually very easy to break - if someone knows how to do it - but it is still very resistant to direct or blunt force impacts.
Laminated glass is usually made with two lites of annealed glass - meaning that if impacted it will likely break as easily as regular window glass - but the advantage of laminated glass is that the plastic interlayer will hold the unit together (despite being broken) and the glass will stay in the frame.
An IG unit (dual pane) with a tempered lite outboard and laminated inboard provides good security and a very good level of impact protection. The exterior tempered will stop most common impacts and the inner laminated will stop whatever gets thru the tempered - and in the event the tempered lite is broken, the laminated (broken or not) will keep the opening closed.
Another option is to get a laminated-tempered glass - meaning that the manufacturer uses tempered glass in the construction of the laminate. This type of make up can be incredibly strong and very difficult to break. It can also be incredibly expensive and the visible distortion may be unacceptable as well. All tempered glass has some visual distortion. Add two tempered lites together in a laminated glass sandwich and you have the potential of serious visual problems.
Another option is using polycarbonate for your window glazing or possibly a glass/polycarbonate hybrid. But, again, the hybrid can be hugely expensive and polycarbonate is going to scratch rather easily and will rather quickly become “visibility-impaired” – not to mention that few if any door manufacturers would even offer that option for that very reason (and a few others relating to things like coefficient of expansion and contraction for example).
Wire glass is an option in some instances (fire codes), but not in your situation since it actually breaks easier than regular “window glass”. The wire embedded in the product weakens the glass cohesive bond making the product brittle.
Dade County has the most stringent glazing impact requirements in the world. If you buy a door that meets Dade requirements, nobody is getting thru it – 2x4 or hammer or baseball bat or crowbar – they are staying outside. But, Dade impact standard does not require that the glass is unbreakable; it only requires that the glass stay in the “hole” in the event that it is broken. Dade mandated impact glazing is usually a very heavy-duty laminate.
Since codes reqire safety glazing in all doors with glass inserts, when manufacturers build a door using an impact resistant dual pane IGU, it is normally a tempered lite and laminated lite in one package. Whether the laminated is the interior or the exterior lite is at manufacturer discretion.
When Dade-approved doors are built using single pane glazing it will be a single laminated lite in place – possibly as thick as ˝”.
Again, any large door manufacturer has these options available - you just have to tell the door salesperson what you want when shopping for your door and then it is his or her job to tell you how painful to the wallet the upgrade to the type of glazing that you want will be.
Linear Mode
