What is Patina?

One of the most interesting things about being a home inspector is how there is always something new to learn. As generalists, we simply aren’t experts on everything, and any home inspector who claims to know everything is one to avoid. That doesn’t mean that the desire to learn more isn’t strong!

One term I learned recently is patina. Of course, I already knew it by the more commonly used phrase copper corrosion. This is simply how copper turns from orange/brown to green and contrary to most scary articles online, is rarely a concern. In fact, I recently recommended for the first time in my years of business, an evaluation of excess patina to be investigated by a plumber. Here is the world’s most famous example of patina in action:

When one thinks of the Statue of Liberty in New York City, we all think of the iconic green color. The simple fact is that the green is NOT what the designer had in mind and the picture on the left is what it would have looked like 100 years ago when it was new: the copper has corroded on the surface giving this green color. As the statue has been monitored and maintained for over 100 and has shown no signs of structual compromise, this can be true for copper water supply lines but a 100 year old copper line should definitely be inspected by a qualified plumber!  

This is about the minimum amount of corrosion I would need to see to suggest a plumber double check the pipes.