Primary Causes of Wood Rot
All kinds of wood include a small amount of water when exposed to air; when the normal level of moisture in the wood increases, it is more prone to rot and further deterioration.
Moisture being one of the important criterions for fungi to survive, it starts multiplying and becomes visible eventually. Temperature in the range of 40°F to 100°F and the presence of oxygen are even more favorable for the growth of fungi on wood.
The other important reason why fungi targets wood is that wood contains carbohydrates in the form of lignin and cellulose, which is a main source of food for the organisms.
In summary, moisture level, favorable temperature range, and presence of oxygen stimulate the growth of fungi thus leading to wood rot.
Types of Wood Rot
There are three types of wood rot:
- Dry wood rot: Alternatively known as brown rot, a dry wood rot cracks the wood over the grain thus making it crumble. The advanced stages of dry wood rot can become powdery and dry.
- Soft rot: This kind of rots affects wood shingles under wet climatic conditions. It is rarely found inside houses.
- White rot: In this type, the affected wood exhibits a yellowish to grayish white appearance. In such cases, the wood becomes soft and has a spongy feel.
Wood Rot Control Measures
Incorporating some control measures are highly recommended to prevent wood rot; here are some handy suggestions:
- If the wood is to be used in a place where it is more prone to rot, then treatment of the wood with a good wood rot preservative would be helpful. You can also choose heartwood belonging to decay-resistant species.
- Use the wood on a site that is well drained. Install effective gutters, drain tiles, and downspouts. Avoid keeping untreated wood within a distance of 18 inches from floor.
- Use sufficient cross ventilation under the buildings to get rid of deceased air pockets.
- Installation of a vapor barrier on the surface of the soil will be highly effective as it condenses the soil moisture.
How to Kill Wood Rot?
Once affected, it is not very easy to get rid of wood rot completely. Though there are many commercial products available for the purpose, they are not very effective. However, there are two common inexpensive materials that can be used for the treatment of wood.
Firstly, a mixture of borax and boric acid called borate is one product that can be used to kill rot organisms in the affected wood; it can also be used as a control measure.
Secondly, you can make use of ethylene glycol for killing the wood destroying fungi and the rot spores. This is available as an automotive coolant/anti-freeze and is highly effective. Borates mixed with anti-freeze also work efficiently.
So there you have some wood rot control measures, the major wood rot causes, and suggestions to kill wood rot.
Home Inspectors Blog: Wood Decay, John M. Acaron
West Virginia University Extension Service: Wood Rots (PDF), A.R. Biggs and K.S. Yoder
How to Prevent and Cure Timber Rot, Nicholas Clifford