Technical Debating Tempered or Laminated for Door Glass

Hi All,

I've read other threads about the debate of tempered vs laminated glass. Most suggest to use tempered for side and doors and it does make sense why.

On my chopped shoebox the driver side rear has a vertical crack (see photos), and the passenger side door is cracked severely in multiple places. I was told the passenger side window was installed improperly. I was able to trace the issue and fix it and the window seems to stay in place properly and go up and down nice (albeit glass is all cracked)

I'm hoping to find a local glass company here in San Diego to help me out but am not sure if laminate would be ok given all the rest of the glass is laminate (from what I can tell)? I don't see any cracks in any of the glass in other places so I'm not sure if going with laminate to keep it all the same makes sense or not and I don't want to replace any of the other glass that has no cracks. Its possible the rear driver side was installed without a bit of isolation from the body metal or the garnish molding pinched it tight in some spots. I'll have to look into that further.

Any opinions? I'm pretty careful with slamming doors and if someone else will be the passenger I'm likely to tell them not to slam it. Although I just installed new seals on the doors which is making them a pain to close so I'm hoping with time I won't have to close hard. The only other concern I have is the road conditions in San Diego are terrible right now especially for an old car with bias ply and airbag suspension!

Here are some photos of what I pulled out.

 

I used new laminate glass in my doors, replacing the old factory laminate glass. Tempered glass will shatter into small pieces if broken. Laminate glass will hold it's shape and not shatter into small pieces when broken.

 

I think you'll find custom tempered glass will be considerably more expensive compared to laminated. Either type needs to be installed with as little stress applied when in place, tempered is more forgiving of poorer runner conditions.

Tempered glass has to be cut to shape before tempering, miss the sizing even a little and you'll have a paperweight. Laminated side window glass was typically used until the early '60s when curved side glass appeared. Rear windows have been tempered since the 40s for safety reasons.

 

Thanks, it seems I may be better off with laminate and babying the car. I tend to baby the car anyways. It will see low miles (200 miles a year if im lucky) and not stay outside overnight ever.

 

Make sure all the window 'fuzzies' (especially in the runner channels) are present and in good shape and the tracks are parallel. Glass to metal contact will cause problems. Loose or tight fits will also cause problems. Any fixed glass has to be gasketed a bit loose to allow slight movement with sealer applied to the gasket to prevent leaks.

 

Thanks, I may take my time and remove the passenger rear window as well and make sure it's all together correctly with some isolation material so there is no metal contact. I can see the body flex or hitting a pot hole causing more glass issues the way it's set up right now by the previous owner.

 

I like tempered. My brother had an OT car that got rear ended which put a twist in the tailgate. The glass bent but didn't break.

 

Down under now we are required to fit tempered side glass. For incase of an accident and the door wont open a bystander can break the door glass. A lot of commercial vehicles have a small sharp hammer attached near the window for such a reason.

 

Some day he will hit a bump on the road and that window will be a pile of glass chips. I've not ever seen tempered glass survive very long after being bent, you can bet it has stress cracks and its just a matter of time before it self destructs. There are reasons you hardly ever see tempered glass with cracks, its not their nature to crack.

To the OP, invest the money to buy and install all new window fuzees and window tracking before you install the new glass. Its likely the glass flopping around loose in the channels has caused the cracks you now have. Many of the old rubber window tracks were held in place with very small screws that the glass couldn't reach because the fuzees kept the glass away from them, but as time killed the fuzees, the glass can now reach those screws. Those screw heads and the flopping of the windows in the loose tracks is causing most of your cracks. Installing new glass without replacing the wore out rubber and soft material around the glass just subjects the new glass to the same problems that cracked the old glass.

 

That's a good point.. I think if something happened I'm not getting out of this chopped shoebox with the windows broken out unless I stay super thin

 

Thanks for the advice you should see the potholes in San Diego right now! Just a matter of time before I hit many of them.

As far as the door glass it came out of the track and was banging against the door metal severely so over time it must have cracked really bad. I can see why it happened and I adjusted the track so it won't come out but I need to replace glass now that I found the culprit. I'm still messing around with the rear driver side window but will make sure to add material to keep it isolated from metal. There was none in some areas.

 

I've used Hot Rod Glass in Riverside for many years on countless projects. I have always purchased tempered glass because old Fords have a tendency to crack door glass.If you send them the correct fitting pattern what they send back will fit. I make my patterns out of 1/4 inch tempered Masonite then transfer it to a plastic sheet that can be rolled for shipment. Tempered glass from them is not more expensive than laminated. Next time I will also order my windshield glass from them because for this last deuce sedan it took 2 glass shops and 5 tries to get it right.

 

Thanks! I will look into them as an option.

 

Anyone know if regular clear tempered glass from a shop that makes bath mirror, etc glass would even be a suitable option? I found a local company that can do it but only if it was clear tempered. My guess is I should be looking into something auto grade and I'm also somewhat leaning towards laminate to be consistent with what's already in there but not opposed to tempered although I would like the tint to match the green from what I already have.

 

The glass shop cuts the glass and sends it out to be tempered. Doesn't matter if it is clear or tinted. Any glass shop should do it.

 

Your glass shop may not want to invest in a sheet of tinted plate. Freight may also be an issue as they buy their clear sheets in bulk?

 

One glass shop that responded said they can do it with a standard tinted green but if I needed it matched better it would be additional cost. One thing I don't understand is the difference between laminate glass from any shop vs laminate glass that is auto grade. If it's tempered glass it won't matter if it's auto grade is what I'm gathering from the previous responses.

 

Two different animals entirely.

Tempered glass is doing it's job before an event, when the pane is intact. It will resist breakage from an impact, and is generally 4 to 5 times better at this (stronger) than a laminated pane. It has the bonus of breaking in a 'cubed' fashion, which will limit the possibility of injury when a breakage does occur.

Laminated glass will not resist impact anywhere near as well, and will fail when exposed to much less of an impact event. It is designed to come into it's own after the pane has failed. The PVB interlayer will essentially hold the glass to itself, which works much better at limiting injury.

Front windscreens use laminated glass for the added safety of intrusion resistance. They have a quite thick interlayer between the two glass sheets to try and stop things entering the interior space at speed. They are also curved outwards, which greatly increases their ability to withstand and deflect objects head-on.

My advice? Tempered or toughened glass is a better choice for side/rear vehicle windows, especially if the pane is flat. Having no curvature will lessen impact strength too much for laminated to hold up as well. Tempered will live much longer in the application.It is pretty strong stuff...........

 

If you are meaning that when you look at the edge of the glass it is green, that is just normal 'clear'.
You can get a 'super clear' that has no colour at all, but the industry standard clear has the green tinge.

 

I mean looking at the glass in the photos in general not the edge itself..

 

Cool video thanks. I see why tempered would be better for the side/door glass.

 

Sorry if I asked this before but I want to make sure I don't mess it up. If I go with a glass shop that doesn't specialize in auto, for laminate I would need to ask and make sure they are using an auto grade? If they are going to temper it won't matter if its auto grade or not? I'm aware laminate glass for autos is a different grade from what a general glass shop may offer from what I've read in other threads.

 

Automotive grade laminated glass has a thicker interlayer between the two laminated glass sheets.

Tempered glass will be monolithic (one single sheet), and will need to be cut, shaped, ane edged before the heat treatment. Once tempered, it can not be worked in any way.

 

Thanks! So for the tempered there isn't a specific grade for auto? In other words any shop can make tempered and it would hold up for auto use? I do see how the automotive grade laminated would be specific for auto use.

 

The bad thing with laminated glass is the individuals who think that they have to slam the doors on your old car with laminated glass. Normally that is how the crack that SDrocker showed in post 20 happen. Someone rides with you and gets in or out and slams the door. My wife is the absolute worse at it as she is heavy handed on anything she handles.
Being as I am stretchin my doors 9-1/4 inches I am having tempered glass made and that means hauling the truck down to Crazy Steve's hood to have (Vancouver) to have it done. I'll probably use up a 4 x 8 sheet of 1/4 inch masonite making patterns that fit first though.

 

In this particular case the window fell out of the track (according to the previous owner) The track wasn't installed properly when I analyzed it further but I was able to adjust and make it fit and work well. I can see the window getting cracked from slamming the door. I plan to baby the car if I do go with laminate even if I end up with a significant other that goes on the car ride with me.

 

If the fuzzies in the window channels are good, the glass isn't 'loose' in the channels and everything is adjusted correctly, slamming a door won't break the glass. It's after the glass gets loose or slightly 'bound' from wear/maladjustment that the problem appears.

I'll agree that tempered glass is more tolerant of those conditions, but I've never had a window break unless the glass wasn't fitting properly anymore.

 

One more thing I'll note. I have noticed that the current laminated glass some shops use isn't quite as thick as the original OEM glass, allowing a bit sloppier fit which doesn't help. I don't know if this is another artifact of 'metrification' of some supplies or a choice on the part of the shop.

 

Hmm that is quite interesting! The glass I took out (and showed in the photos) does measure right at the 1/4" mark.

 

...... assuming the window is wound all the way up when the door is slammed.

This is probably laminated glass with a thinner interlayer.