The Impregnation (chemical Protection) Of Lumber

The natural enemies of building lumber never sleep therefore it is reasonable to use some chemical conservation materials to protect the wood from decay or ligniperdous (wood consuming) insects.

Wood protection products

The market offers lots of wood protection (impregnation) coatings. Most of them are of green or brown color (coloring of the impregnation fluids helps you identify better which areas were already protected and which areas still need to be impregnated), but you can buy also translucent protective coatings (for the interior wood).

The most of these wood impregnation products are environment friendly, they do not contain formaldehyde, heavy metals (e.g. lead) or chlorine, neither the carcinogenic or mutagenic chemicals.

How to impregnate the lumber with wood protection fluid

The lumber surface must be clened of old stain, mud, phloem and fibre.

To achieve the best protection, it is also necessary to remove all surfaces attacked by dry rot and wet trot fungi or mildew.

Wood impregnation process

The following wood impregnation processes can be used:

1.) vacuum/pressure application. The pressure impregnation is the most effective way of wood protection. It uses the water dissolvable fluid based on organo- and anorgano-metallic compounds of copper and boron (without chrome additions). Thinning ratio from 1:10 to 1:100;
2.) dipping in the protection fluid. Second most useful solution by which the lumber is dipped in the tanks with the protective coating. Thinning ratio 1:4 to 1:10;
3.) spray application. Also not bad but it requires the fluid to be more concentrated (thinning ratio 1:4, means you need much more of the protective fluid than by dipping or pressure application) and doesn´t impregnate the wood as deep as the above two methods.

All the above protection methods need the wood to be dry enough to strat the impregnation (20% humidity).
All the above impregnation processes definitely help to extend the durability of the building lumber very much. For example the soft woods like larch or spruce wood after impregnation can last more than 20 years (exposed to weather, fungi and insects). Harder woods (oak, beech, etc) will live even much longer if impregnated properly.

After this period the impregnation has to be renewed to assure the lumber properties.