What Is Wood Rot?
In biological terms, wood rot is the decomposition or decay of wood. In homeowners’ terms, wood rot is a problem that everyone has to worry about. Any decay in the wood holding your structure together can cause serious problems.
Roof decking, support posts, and ceiling joists are mostly made of wood, making wood prevalent building material. These materials need an extra layer of protection against fungi that cause rotting. To protect them, you need to understand everything about wood rot including its types, signs, problems, and ways to prevent it.

Types of Wood Rot
Not all wood rot is the same because each manifestation comes with a specific set of destructive enzymes and attacks differently. It can be classified into brown, soft, and white rot according to different fungi types that cause the rotting.
Brown Rot
Brown rot is also called dry rot because the rotting wood appears dry on the surface. The fungi that cause brown rot targets the wood structure cellulose. As it destroys the cellulose, the wood begins to shrink, turn brown, and break into bits, causing what is called cubical fracture.
This type of rot starts as a very tiny molecule but spreads rapidly as soon as it attacks. It can thrive at a temperature of 65 to 90 degrees.
Soft Rot
The fungi responsible for soft rot secrete enzyme cellulose that generates tiny holes in the wood. The fungi thrive in very hot, cold, or wet areas of between 0 and 110 degrees.
Once it attacks, the wood discolors and begins to crack, but this process is slower than the brown rot. It leaves the wood with a honeycomb-like appearance. This mostly attacks trees and logs, but it can also wreak havoc in homes as long as conditions allow for it.
White Rot
White rot on the wood comes with a light yellow or whitish shade with a spongy feel. This rot attacks both the structural cellulose and the lignin of the wood. This occurs when you expose your wood to temperatures of between 65 and 90 degrees.
There are many types of enzymes that cause white rot and some can be so strong that they oxidize the lignin. A good example is the honey mushroom, which attacks live trees and can cause immense damage. Some of the enzymes appear so harmless and are even edible. Take the example of the delicious Shiitake mushroom.
Signs of Wood Rot and Where to Look
The best way to prevent wood rot from causing massive destruction is to identify the signs early enough. Consider inspecting your home for signs of wood rot annually. There are a few locations that are likely to experience trouble.
Check those areas exposed to humidity, such as the crawl space and the attic. Check underneath cracked paint as it can also hide rotting wood. Here are some signs you should look for when inspecting your house for wood rot.
Swelling and Discoloration
Check the siding around your windows to see if you can notice any unusual colors and swelling. Poke your siding using a screwdriver so that you don’t miss anything behind the paint. If you notice that the screwdriver sinks into the wood, you should know that you have a rot problem.
Soft Wood
Normally, your structure needs to have hard and firm wood. But when rotting begins to creep in, the wood softens and starts to shrink. It might also feel spongy, crumbly, or brittle. Your timber will then start to rot. You can remove the rotting portion, so it does not affect a large area.
Musty Smell
If areas such as the crawlspace start to feel damp with a musty smell, you should know that there’s an active rot taking place. Start working on finding the source of the smell and solve the problem immediately.
Mushroom-Like Bodies
Mushrooms may fool you with their beauty and harmless appearance. But they’re an indication of a problem that you shouldn’t overlook. If you notice the bodies have wide pores, you should know that the rot has affected your timber.
Dust-Like Spore Patches
As the rot eats away at your wood, you’ll start noticing large patches of dust-like spores. Be careful because some of these dust-like spores may not accompany any rot, but that doesn’t mean there’s no problem. The spores often take rust red, orange, or brown colors.
Wood Rot Prevention Tips
- When doing your decks, consider using pressure-treated or decay-resistant lumber.
- Paint all sides of your wood before assembling it into your home interiors.
- Clean the gutters to clear clogs that can cause moisture buildup.
- Consider using rot-resistant wood such as redwood, mahogany, teak, cedar, and white oak.
- Use dehumidifiers in a house with high humidity.
- Sweep away standing water away from your home as soon as it stops raining.