Urethane – The Windshield Glue

The most important thing about how your windshield is attached to the frame of your car is in the glue.

The glue, or adhesive, used for windshield installations is called urethane. It is a deep black type of glue that gets onto everything it touches.

Just a tiny dab can permanently ruin your clothes, stick to your hands and mark you for weeks, and destroy the interior of your car by sticking to your dashboard, headliner, or visible part of the framing.

But when properly applied it can save your life!

Urethane Windshield Glue

When did we start using Urethane?

As automobiles developed over time, safety issues required that cars be built tougher and safer each year (not much has changed, huh?). As far back as the 1920’s cars started using a 2-layered glass combined by a center layer of cellulose (now we use Polyvinyl Butyral) for the windshield glass. This new type of glass kept windshields from breaking into large, sharp pieces that were potentially harmful, even deadly in case of an accident.

These larger – and heavier – windshields required a steady, strong adhesive to bind them to the frame of the automobile, since the old rubber gaskets weren’t enough to safely support their weight.

Behold — Urethane!

How long until I can drive my car after a windshield is replaced?

This ultra adhesive, super sticky, get-on-everything black glue is very strong and cures (dries) in two hours or less (the most commonly used in most vehicles today cures in one hour).

On Auto Glass City’s windshield installations in the state of Florida, due to the heat and high humidity here, your car will be ready to drive in one hour after your windshield replacement.

How is urethane used on auto glass?

Urethane is only used when attaching a piece of auto glass directly onto the frame of a vehicle, as in the case of a windshield replacement.

Some auto glass pieces, such as driver door glass that rolls up and down, won’t require the use of urethane since the glass is attached to mounts inside the door of your vehicle.

Other auto glass pieces – including some windshields, like the ones for tractors and such – may be attached to the vehicle using rubber gaskets. The glass would be set onto the rubber gasket that attaches to the frame of the vehicle to hold it safely in place. This method is not typically used on heavier glass like windshields for obvious safety reasons.

Urethane has the strength and resistance needed to withstand high impacts. It is extremely important that it is applied properly by using the right primers and safe drive-away times so that it may perform well in case of an accident and avoid – even fatal – injuries.