Waterborne finishes are coming of age

Many of us are still holding back on making waterborne finishing part of our repertoire. This is certainly understandable since waterborne finishing materials have acquired a bad reputation in past years. I resisted as strongly as anyone else when I first saw examples of waterborne finishes. But things have changed.

With the increased popularity of “going green,” conventional wood finishes have come under scrutiny. The reason for this is that conventional finishes contain solvents that are volatile (they evaporate rapidly) and are hazardous to people and the environment. However, the technology required to create safer finishing materials that have the same qualities as conventional finishes has definitely lagged behind. The most promising substitutes, waterborne finishes, are just now beginning to fulfill this need. Several products on the market today have overcome the shortcomings that we’ve seen and heard about in past years.
The challenge for woodworkers looking to get on board with waterborne finishes is two fold. First, we need to find the materials that will work best for us. Secondly, we need to learn how best to apply them. The materials themselves must meet three criteria:
  1. They must meet our standards for health, safety and environmental friendliness.
  2. They must look good.
  3. They must be durable.
Nowadays, almost every manufacturer of finishing materials sells products that they call green or sustainable. Some are certified by an outside agency, some claim potential contribution to LEED credits. We need to look beyond these standards to find out if a given product is really green, especially in regards to the health and safety of workers in our shop. The best place to start is to examine the Material Safety Data Sheet (MSDS) to see what hazardous ingredients a product may contain. Some internet investigation* can help us make a determination about whether or not we feel comfortable using a particular product. After all, if we’re going to the trouble to change over to greener finishing materials, we need to know all aspects of how green they really are.
Once we know that we have at least reasonably safe finishing materials, we need to be sure that the results look good when applied to our wood products. It’s not necessary to settle for something you’re not happy with. There are waterborne finishing materials out there that really can produce a beautiful finish.
Another concern is how the finish holds up when put to use. It will need to have adequate adhesion, adequate resistance to heat, abrasion, impact, moisture and chemicals. Other factors may need to be considered depending on the particular application. If you can obtain a certification or test results from an independent agency, that’s the easiest way to find out what to expect, and it doesn’t cost anything. Some manufacturers will provide reliable test results, as well. If test results are not readily available, you can perform most of them yourself. Specialized testing may need to be done by a testing lab.
So after we find a material that is safe and dependable, and we’ve seen a finish sample that looks good, we still have to make it work for us, on our products, appealing to our customers.
Since the finishing process contains several interdependent steps, we need to find the combination of finishing materials that creates the best results. The most straight forward approach is to switch to waterborne finishes for the whole process. Since waterborne finishes use distinctly different chemistry than conventional solvent borne finishes, this approach minimizes the potential for compatibility issues that may arise from using dissimilar materials.  
In some situations, we may decide to change only part of the process over to waterborne finishes. If this is the case, we need to consider compatibility issues very carefully. For one thing, we must be sure that the stains, sealers, glazes, topcoats, etc., will adhere to one another. That means testing the whole finishing process under conditions similar to production before we apply it to an actual job.
I realize this process may sound like a lot of work, as it is with many worthwhile endeavors. However, the time, effort and/or expense will pay for itself now and in the years to come.  The finishing process has traditionally been the aspect of woodworking that has the greatest negative impact on people’s health and the environment. Potential customers will favor a company that has taken the effort to find a cleaner alternative. This is especially true if you plan to bid on LEED jobs. Also, you gain the advantage of being ahead of the game when government regulations require companies to comply with stricter standards for worker health and pollution control.
*Some internet sources of information on hazardous ingredients:
The New Jersey Department of Health Factsheets

Ed. note:

With his background in teaching along with his extensive research in waterborne finishing, John Howell now runs a consulting business, helping companies make the transition into using waterborne finishes, amongst other things. This help includes teaching finishers how to use these products effectively as well as showing management how to take advantage of the benefits of waterborne finishes. John still restores antique furniture, as well, always researching and testing new products and application techniques.