Window of Opportunity? Tony Passwater, BodyShop Business, September 1998

If you thought glass installation would be a simple, trouble-free profit center, think again. Properly replacing glass is just as complicated as properly repairing collision damage

If we think we have it bad … tough competition, controls by others outside the industry and liability exposure, just look at the glass industry and its world.

Afterward, be happy you're in the collision repair business!

Unfortunately for us, the glass industry is going through what our industry is apparently heading toward. Consolidation will ultimately affect pricing of our services, decrease our repair turn around times and increase competition of convenience.

To think … some time long, long ago, the retail list price for glass was really the retail list price for glass.

If you're thinking about doing your own glass work and you've weighed all the factors, I have two statements for you. If you answer "true" to both, then it probably is a necessary strategy for your future:

1. Your volume of glass work internally and/or externally makes this venture profitable.
2. No one in your area has the proper skills, or they don't provide you quality service.

Business Decisions
Taking on glass installation would be no different than any other business venture. You need to have a reliable and competitive wholesale source, a staff with the proper skills and certifications, up-to-date tools and materials, and the time to properly manage the business. Without all of these in place, you surely wouldn't consider entering into this arena, would you?

Keep in mind, even if you elect not to enter the glass-installation business, you still need to understand the procedures necessary for proper installations and the liability you continue to incur. Whether you actually do the work internally or sublet it to another company, in most cases, you're still liable. Unless the glass installation is direct billed to and the contract is directed by the insurer, the vehicle owner has a contract with you, not with whom you elected to do the installation. For this reason, it's important that you're very well informed - even when contracting someone to perform the glass work for you.

To do this, let's examine some areas of consideration.

The Source
Your first area of consideration is your glass source. It'll be difficult to achieve discounts on glass to a competitive level with normal, small purchase volumes. In fact, most collision repair facilities have found they can establish contracts with outside vendors to do the complete job, including the cost of the glass, for what they can buy the glass for. Their profit, then, is realized through an acceptable mark up on the glass plus the installation labor and materials.

This doesn't solve the problem if the source is unreliable or you just don't receive the service you need. In these cases, you may elect to re-examine your sources again. Send a bid letter explaining your needs to all vendors, and ask them to bid on your account. Include your last year's annual purchases in glass replacement and other glass needs, plus set a contract time frame, such as one year. This gives vendors an idea of your anticipated volume and some security in their investment for your account.

Glass Standards
The role of glass today is not just to stop bugs from getting into our eyes. Glass plays an important structural role as well, and this role is predicted to increase in the future.

To help ensure safe installations - along with safety in general - The National Highway Transportation Safety Administration (NHTSA) develops Motor Vehicle Safety Standards (MVSS) for vehicles sold in or imported to the United States. The windshield and its installation method (original manufacturing) must be able to pass two performance standards: MVSS 212 and MVSS 216. These two tests, even though they're designed for vehicle manufacturers, have also become the standard for aftermarket repairs since we are - by default - contracted to restore the vehicle to pre-accident condition.

• MVSS 212 - Commonly called the windshield retention test, MVSS 212 requires the windshield to keep the front-seat occupants from exiting through the windshield in a frontal collision. The test is performed at 30 mph into a fixed barrier. The windshield must maintain at least a 75 percent perimeter after unrestrained occupants hit the windshield.
• MVSS 216 - Commonly called the roll-over test, MVSS 216 requires the windshield and A-pillar area to withstand 1.5 times the weight of the vehicle directed downward at the front of the roof without crushing more than 5 inches during the two-minute test. Since roll-overs vary greatly, this test is performed with a crushing panel applied to the front of the roof. The vehicle must be secured so the suspension isn't a factor, and all other windows are closed, such as sunroofs and doors.
• MVSS 208 - This is another standard that indirectly affects the replacement of windshields. Although this standard is designed for passenger air-bag deployment, in the specification it acknowledges that the passenger air bags designed to rebound off the windshield for proper positioning will do so with a force of 300 pounds per square inch. Therefore, for proper placement of the passenger air bags, the windshield must be able to withstand this force without being pushed out.

The preparation, method of installation, adhesives used, temperature and humidity during installation, and the proper cure time all directly affect whether the installation will meet the above three safety standards. For these reasons, it's very important to distinguish between glass installations from the past and what's required today. Even auto manufacturers have specific requirements that differ from each other.

The Tools
Today, specialty tools have become commonplace for glass installations. Electric or pneumatic power cutting tools, inflatable bags and suction cups have replaced the cold knife and piano wire in many applications. These methods allow for the removal of some very difficult glass designs, but they require training and practice - otherwise, the glass and interior trim may be damaged.

Even with conventional tools, training and understanding are needed. One common mistake made when using the common cold knife is not properly sharpening the blades before using them. It's also important that the blade be positioned properly when pulling it through the urethane. The cutting blade section should rest as close and parallel to the glass surface as possible when cutting. When this isn't accomplished, the blade or glass breaks and pulls through the urethane like you're pulling against a team of horses.

Materials and Preparation
Before windshield retention standards were implemented, most windshields were installed with butyl tape or set in a rubber gasket. The primary purpose of these methods was to keep the windshield from leaking and to set it in something flexible so when the vehicle body flexed, the windshield didn't crack.

Butyl tape supplies a bonding strength of approximately 13 psi. This, of course, is far from the passenger air-bag deployment pressure placed on the windshield in the MVSS 208. However, it's possible for a butyl tape installation to pass the MVSS 212.

Since the Motor Vehicle Safety Standards don't provide a minimum strength for adhesives (except by indirect means), auto manufacturers have their own standards or OEM specifications. The OEM-approved urethane adhesives today supply more than 600 psi of tensile strength, and there hasn't been any adverse effect identified with using an adhesive that's too strong, just too weak.

Unfortunately, there are other factors that affect the installation besides the adhesive specifications. These include surface preparation, curing time, temperature, humidity and the size of the bonding surface. As it's been stated, "A chain is only as strong as its weakest link." Any one of these can easily cause the installation to fail.

Installation Method
There are two basic types of installations: full cutout and partial cutout (Figure 1-1). Note: Auto manufacturers may have specific recommendations for the type of installation they approve, and it's important to follow these recommendations as outlined.

The full-cutout method removes all or all but a very thin layer of the OEM adhesive, while the partial-cutout method leaves the majority of the OEM adhesive in place.

Generally, auto manufacturers will have guidelines regarding whether a partial-cutout method is approved for their vehicles but, in many cases, the condition of the pinchweld area will dictate a full-cutout method, even though the manufacturer allows otherwise. If the pinchweld area is damaged, it's likely the adhesive will be removed completely in the repair area. This then requires a full-cutout method.

Using the partial-cutout method (if approved) is best advised immediately after cutting out the old windshield. This ensures a very clean surface for bonding. If the windshield isn't installed immediately, it's best to cut another layer to expose a freshly cut urethane bonding area or perform a full-cutout method.

A special note should also be made in regard to repair work in these areas. All metal work areas where an adhesive will be applied should be "metal finished." In these areas, no plastic filler should be used since its adhesion characteristics are lower than urethane adhesive. Also during refinishing, pinchwelds should be primed with the appropriate epoxy or self-etching primer but generally not topcoated or cleared. Again, the paint system could be considered the weakest link.

Surface Preparation
Proper preparation before installation is critical. The glass surface where the adhesive is to be applied must be properly cleaned - or the adhesive won't be effective. This includes using a complete system designed by the adhesive manufacturer. We've finally learned not to intermix systems with our refinishing products, and it's extremely important to stay within a system when preparing glass for installation too.

The cleaning begins with a glass cleaner designed for the system, which won't leave a film or residue. Even a finger print in the adhesive area can cause the adhesive to fail during testing, so this step must not be overlooked.

Some systems will require a special primer be applied to the glass. This primer may or may not be the same primer recommended on the pinchweld area. In some applications, an additional ultraviolet (UV) protection coating may be called for if the glass doesn't already have it applied.

In the pinchweld area, special primers are designed for any bare areas before application of the adhesives. Any loose original adhesive must be removed, and the original urethane must be clean. Since urethane can be porous, it's not normally recommended to use a solvent-type cleaner. Water can be used, but the area must be dry before installation. Again, the adhesive manufacturer will have specific recommendations for these conditions.

Curing Times
You've probably heard phrases such as "ultimate curing time" and "safe drive-away time" when discussing adhesives. But be very careful when considering what these phrases actually mean; they may not be referring to what you think.

The ultimate cure time is simply the time it takes the adhesive to fully cure. The safe drive-away time refers to the time it takes to reach or exceed MVSS 212. Wait a minute, what about the other two standards? Because these phrases are often used too loosely, they may imply something you don't mean. Make sure to ask specific questions.

Also, the ultimate cure time and the safe drive-away time are sometimes ignored to facilitate speedy delivery of the vehicle back to the owner. Some adhesive advertising may even loosely use these terms for a competitive advantage.

Keep in mind, if you install (or have installed) a windshield and the adhesive isn't totally cured or doesn't meet all three safety standards and you deliver the vehicle to the customer, you've exposed yourself and the company to an extreme liability situation.

If the customer (or employees, for that matter) has an accident in the vehicle and the adhesive hasn't properly cured to exceed these standards, this installation could cause personal injury or death. If this happens - whether you personally installed the windshield, had an employee do it or had another company do it - you are liable. You may be asking yourself, "What's the chance of the vehicle getting into another collision on the way home?" It's not worth the risk, believe me.

Temperature and Humidity
Different adhesives are designed for different weather conditions. Some may be single component while others may be two component. They all have a specific range of use for which they were designed, so it's important to know the specifics of all products in the system and make sure they're used accordingly. It's also recommended to allow adhesives to dry naturally unless specifically designated otherwise. Heating units normally aren't advised for most adhesives.

Not only is temperature a factor, but so is humidity. Urethanes used today cure with the assistance of moisture in the air. So even if the room temperature is above 70 degrees F, it's possible to have very low humidity, which will hinder proper curing times. For situations such as this, it may be necessary to use running water to increase the moisture content of the air.

Proper Bonding
Even after proper surface preparation, the adhesive still must have a large enough area to bond to the glass properly. The minimum bonding area is at least 1/2 inch on the bottom side of the glass (Figure 1-2). The strength of the bonding is obtained from this 1/2-inch surface, not from the edges of the glass.

Sometimes, a damming strip or tape is used as a backstop for the urethane adhesive. This damming strip is placed down on the edge of the pinchweld. Note: Using these damming strips may not be possible on very narrow pinchweld areas. Even if the automobile and adhesive manufacturer allow the use of a damming strip, it must not take from the 1/2-inch area for the adhesive (Figure 1-2).

It's also important to understand that these damming tapes or strips don't provide sufficient bonding for an immediate "drive away." They assist in holding the glass in place during curing, but this doesn't meet all safety standards.

Documentation
Having a method of documenting or receiving documentation from your vendor about these installation factors is also extremely important. The following information should always be documented when the installation takes place:

1. Date and time of installation.
2. Vehicle information (year, make, VIN number).
3. Owner information (name, address, repair order).
4. Installer information (name, company).
5. Location of installation (where, inside or outside, temperature, relative humidity).
6. Part information (name, part number/NAGS number, clips and moldings replaced).
7. Adhesive (brand, part number, batch number, primer used).
8. Installation method (full or partial, dam type used).
9. Release (date and time).
10. Additional notes.

Without this documentation, you have no proof of the method or products used if there's ever a question regarding proper installation. Many pre-made forms are available to document this, but what's important is that you do it consistently. Whether you do the glass work internally or sublet it, you need documentation for every job.

Managing the Business
The collision repair portion of your business requires proper management to perform and be successful. And, if you elect to venture into the glass business, you need to have the management skills and knowledge for this industry too. There are national, state and local associations for the glass industry to help you do this, just as there are for the collision industry. I've had the opportunity to speak with these glass-specific groups in the past, and they offer a valuable service to their membership.

The key here is to not take for granted the skills and investment required to perform this service. And don't forget the liability issues involved, which can be extreme; some of the awards given by the courts in the last several years have been in the millions of dollars.

If you thought auto glass installation was easy and that anyone could do it, think again. The knowledge and skills required today for proper glass installation equal the knowledge and skills required to properly repair collision damage on today's vehicles. And, as with collision repair, glass installation isn't for everyone. The question is: Is it for you?

Contributing editor Tony Passwater is a long-time industry educator and consultant who's been a collision repair facility owner, vocational educator and I-CAR international instructor. He's taught seminars across the United States, Korea and China and is currently an industry consultant. He can be contacted at (317) 290-0611 or Tony.Passwater@aeii.net.