Last month, our shed burned down, taking with it at least one of our large stately cedar trees. The cause? A chemical ingredient (penofin) in the stain being used on our house.

It turns out that penofin self-combusts in the presence of air, so when our contractor placed one small brush, one empty can and a small rag just outside the shed, eight hours later the fire began. If one reads the very small print about this ingredient (found in several wood stains), the manufacturer details that all tools and containers used to apply the stain are to be placed in a tub of water for a week to avoid combustion.

When I talked with the fire inspector, he informed me that four recent fires he had written investigation reports on had penofin as the cause. When I asked why on earth would such a product be available, he replied that because it is an epoxy (rather than a resin), it does a better job of protecting structures from the elements. Once the product is applied and dry, self-combustion will not happen. We were evidently about 20 minutes away from losing our house and starting a major forest fire on the north end.

The purpose of this communication is to warn residents about the perils of using products with this ingredient and to urge users to follow the instructions carefully. The other fact I have discovered is that not all manufacturers state that penofin is an ingredient in their product, rather placing it under the category “proprietary ingredients.”

— Karen Gardner