While I am out visiting customers, I see quite a few who are due for their IGCC or NAMI certification tests for insulating glass (IG). Passing IG certification testing continues to be challenging for some fabricators. Quality employees are hard to keep and there is oftentimes a high degree of turnover, which leads to a need for constant re-training on the factory floor. Therefore, the quality of workmanship on the plant floor takes a hit. Meanwhile, rising costs of components recently compounded by tariffs have purchasing managers looking to reduce costs wherever they can. I totally understand the intent, but IG is not the place to take risks. Too much is at stake. A fogged IG unit (IGU) makes a window useless. Afterall, a window’s most basic function is to provide a view, and this cannot happen with a fogged IGU. Passing IG certification is crucial to success in the marketplace. So here are some basic steps to follow to help maximize your chances of success.
1. Make sure you start with the cleanest glass possible. Failure to efficiently clean your glass can spell disaster. Check the efficiency of your glass washer, water temperature, and water quality. Use a meter to measure parts per million (PPM) of water contaminants, and the pH of your water. PPM should be below 100 and pH should be closer to neutral, like 6-8. Water temperature should be at least 120F.
2. Consider edge deleting your low-E glass. IG sealants are designed to adhere to glass and not specifically to low-E coatings, of which there are many. In fact, the protective coatings applied to low-E products are specifically designed to be non-reactive (non-corrosive) which naturally makes them more challenging for a sealant chemist to design a sealant that will effectively bond to entire variety of coatings.
3. Choose the best IG components. IG sealants may all look similar, but they are not created equal. Spacers, desiccants and sealants are not all created equal. There are different levels of performance to choose from. There are various grades of performance when it comes to choosing IG sealants. Yes, they all come in 55-gallon drums, and the sealants may look the same, but it is the formulations that set them apart. Do not make the mistake of choosing such a critical component solely on the basis of price. As a former polymer chemist, I can assure you that not all IG spacers and sealants are created equal. The actual blend of polymers, adhesion promoters, and UV degradation inhibitors formulated into high-performance IG spacers and sealants will tell the tale when it comes to their ability to stand up under extreme testing and field conditions which may be encountered. These conditions are simulated and accelerated in the certification test. So, choose your IG components very carefully.
4. Train your employees to consistently employ sound workmanship practices. One can deal with field failures by simply sending a replacement unit, but when it comes to passing IG certification, a single failed IG unit can sink the whole test, causing you to fail. Then you must repeat the whole test while incurring thousands of dollars in additional expenses and paying the test lab all over again. Automated spacer applicators and sealant gunning systems can go a long way to ensuring proper and consistent application and gunning techniques and can be especially beneficial in the face of difficulties of maintaining a quality and consistent manufacturing crew. In the absence of automation, strict adherence to sound workmanship practices becomes even more critical.
5. Pay attention to Argon. The gas retention portion of the IG certification test is the most challenging portion. I oftentimes see it as the main cause for window and IG fabricators failing to pass. The IG units must average 90% fill rate at the beginning of the test and 80% after enduring a rigorous series of weather cycling procedures. It really is a tough test so there is very little room for error. Ask a physicist what happens when you have a 90% to 100% concentration of Argon in a confined space while the concentration of this gas outside of the IG unit is only 0.932%, which is the concentration of Argon in the air. They will tell you that nature’s quest to reach an equilibrium causes a very high driving force for Argon to try to escape the unit. It seems that mother nature loves everything to be in equilibrium. Therefore, due to this nearly 100 to one difference in the concentration of Argon inside the IG vs outside the unit (in the air), Argon desperately wants to escape from the internal cavity of the IGU. It will find the path of least resistance in its quest to achieve equilibrium. So, even the smallest flaw in the IGU becomes a path for Argon to escape. These same flaws also lead to moisture vapor infiltration, but your desiccant is working to offset this by adsorbing and locking up moisture vapor. However, in the case of Argon, there is no saving grace. Once the Argon escapes, it is gone forever, and you fail the test.
So, there you have it. Making sure that you have these five bases covered is crucial to fabricating high quality IGUs that will pass certification testing as well as achieve the best field performance. Make sure that you have these five bases covered to give yourself the best shot at passing. It can have far-reaching consequences when it comes to your company’s success in the marketplace.