Understanding Tannins in Oak and how to care for Your Oak Products

What are Tannins ?

All types of wood contain tannins, Oak, Walnut, and Sweet Chestnut are especially rich in them.

Tannins are a natural compound, the same found in tea and red wine, in wood they play a vital role in protecting timber against insects, fungi, and decay.

For Oak, in particular, these tannins are part of what makes it such a strong and durable choice, tannins give oak its natural character and help it last for generations. That’s why oak is widely used for high-quality furniture, flooring, and handmade pieces like our oak doorstops.

Why tannins matter in oak care

Tannins don’t just protect the wood, they can also affect how oak behaves outdoors. When oak is left outside in heavy rain, for example, tannins can wash out of the timber. This may leave temporary brown marks or “tannin stains” on the surface beneath, especially if your oak doorstop or furniture is placed on a porous material like a natural stone.

Although initially unsightly, these tannin stains are completely natural. They ARE NOT permanent and will fade naturally over time as they are washed out by rainfall and exposed to sunlight UV.

How to remove tannin stains safely

While the tannin stains will disappear on their own, you can easily remove them quickly with the right method and solution. Please DO NOT use standard household detergents or off-the-shelf stain removers, these often don’t work and may even lock the stain in.

At The Natural Wood Company, we protect our products with several coats of natural tung oil, which helps slow tannin leaching. If you ever notice staining from one of our oak doorstops or other oak products, simply get in touch with us, we can provide you with the correct cleaner to remove the tannin stains safely.

The beauty of oak

Tannins are part of what makes oak such a unique and characterful material. With a little simple care, you can enjoy the strength, charm, and natural durability of oak furniture and handmade oak products for many years.