Oil-based polyurethane, water-based polyurethane or natural oil?
Q. We are building a new home, and our builder is insisting that our hardwood flooring should be finished with oil-based polyurethane. He says it is the best, but we want a low-VOC finish, either with a water-based or natural oil finish. Is there some reason our builder would try to steer us away from what we believe is a healthier option?
A. Typically, when a builder says you can only have a good finished product with a specific finishing method, it tends to be based on their own comfort level with whatever is being discussed, and it is completely subjective. Part of it is sometimes a lack of education regarding the varied finishing methods. Some builders and remodelers still have a residual feeling and opinion of water-based polyurethane from their initial introduction to the products years ago; possibly not realizing the performance of the products has improved drastically.
It never hurts to introduce new modes of thinking and new finishing methods to your builder and/or contractor with the reason why you are interested in it. Another point to keep in mind is that some of the oil-based products your builder might like are no longer available due to state laws regulating the levels of VOC’s (Volatile Organic Compounds) a product can contain. While the national standard is 450 grams per liter, California has set a limit of 275 grams per liter, and Ohio has set a limit of 350 grams per liter.
Natural paste waxes and penetrating oil finishes also offer advantages for people who want to reduce chemical emissions in their indoor-air environment. They also enhance the natural look and grain of the wood as well as develop a patina over time. Another benefit with these is their high success rate with spot repairs and the ability to minimize small scratches with reapplication of product. The compromise, however, is the need for cyclical maintenance or reapplication, every 12 to 18 months, depending on traffic in the home. Polyurethane-finished floors, by contrast, tend to benefit from a new coat of polyurethane or a re-sanding every 5 to 8 years.
Roy Young is Quality Control Manager for Schumacher & Co. Custom Hardwood Floors in Milford, OH.