How to Minimise Timber Leaching and Tannin Bleed

The timber cell structure can be likened to millions of plastic straws bundled tightly together - so if a lot of water travels down the board it 'flushes' out the tannins in the wood causing the surrounding surfaces to become stained.

Have you ever noticed how discoloured river water is? This is in part due to the tannins from the surrounding trees.

The most common solution is to use a ‘tannin remover’. However, more often this only reduces the ‘natural extractives’ in the timber rather than eliminating them completely.

It may be possible to reduce tannin leaching by washing the timber with deck washes and timber cleaners, although in most cases this reduces, rather than eliminates the tannin bleed.

Tannin stain is not only unsightly, but can it can block the cell structure of the wood preventing it from absorbing timber coatings evenly, in some cases giving an overall dull and patchy look. This means that tannin rich timbers typically need a thorough cleaning prior to coating.

The most effective solution for leaching, is to use a thermally modified timber such as our Vulcan timber.

Vulcan timber has been thermally modified, with almost all of the tannin being removed during this process. This means tannin bleed is highly unlikely, allowing home owners to rest easy.