Why Using Expired Spray Foam Can Be Risky
Material shrinkage is one of the problems associated with using an expired product
Buying and applying expired spray foam can be risky. Sure, you may get a great price, but is it worth it? What you don’t know can hurt you. Some contractors get lucky and everything works out okay, but what can happen when things go wrong? The longer foam material has expired, the riskier it can get. It can be like putting after-gas in your race car. Can you afford to take this kind of risk on a project? One bad project could cost you thousands, the loss of repeat business, the potential for tarnishing your reputation and the worse-case scenario is a lawsuit. Better safe than sorry.
What Can Happen When Using Expired Spray Foam?
Catalyst Decreases Density Increase Yield Decreases
Many things can go wrong with expired spray foam. A lot depends on the formulation. This article explores a few problems, in general, that can occur with expired foam; however, there are many variables that can affect an application’s outcome. The A, or Iso side, is usually more resilient and tends to last much longer than the B side. The B, or resin side, is another matter. Over time, the catalyst become less active until it eventually loses its ability to catalyze the reaction. As a result, you can get a poor application including foam shrinkage. As the catalyst dissipates, the density of the foam increases which means there is a decrease in yield. You may think you have saved money up front, but your yield will suffer. Moreover, the surfactant (surface active agents that enable surface tension for cell formation) can become less stable over time. This is especially true for water-blown spray foam. Water by itself has no elasticity. Surfactants enable surface tension which provides elasticity and the ability to form cells and maintain cell structure. The key point to remember is that spray foam materials are chemically engineered for a fast reaction. The faster the reactivity, the better the cells can form and hold their shape. As the catalyst dissipates, everything in the reaction slows down and isotropic structures (such as cells) can no longer form or maintain their intended characteristics.
Storage temperature is crucial to maintaining chemical reactivity over time. We trust that material suppliers have maintained proper storage temperature. Testing of the material can be done to alleviate the concern of inadequate storage temperature. A way to check spray foam material you may have on hand is to mix some A and B together (by hand) and see what density you get.
What Should Smart Material Buyers Do?
If you run into an incredible deal, be sure to ask questions before plunging in. Has this foam material been taken off the market for any reason? What is its shelf-life and expiration date? Get a copy of the technical data sheet to ensure that the product is specified correctly for your application. The technical data sheet should also provide viscosity and reactivity information. Ask about the free-rise density and in-place density. Spray foam material can be specified one way in the lab and another way in the field. Just because you’re buying closed cell foam from one supplier doesn’t mean that the material will be the same when you buy it from another supplier. The formulations could have different specifications, and that could make all the difference when trying to apply spray foam in a consistent manner.
Remember: Different formulas have different shelf-lives and possibly different specifications. Be aware of the expiration date. It’s safer to deal with companies that practice good quality control and have technical data sheets on hand that they can provide to you quickly and easily. Never shy away from asking good questions. Your reputation and future business depend on it!
“Information is like compost; it does no good unless you spread it around.” ~ Eliot Coleman