We get a lot of calls from Orange County homeowners who tell us they have damaged wood on their homes that they would like to have repaired. When we ask them what caused the damage, many of them don’t know. In last month’s newsletter, we discussed the different types of termite damage, and how to deal with it. In this article, we will discuss dryrot and how you can get your home back into top shape.
The different types of dryrot
Dryrot is caused by wood-destroying (decay) fungi. These decay fungi are living organisms that live on dead trees and lumber products. There are three main types of dryrot that do major damage to our homes and buildings:
• Brown rot
• White rot
• Poria incrassata
What does brown rot damage look like?
Brown rot is the most common of these wood destroying fungi. Severely decayed wood is dark brown in color, and breaks up into irregular chunks resulting from shrinkage cracks, both across and in different directions of the grain. Brown rot will cause wood to lose strength and lose structural integrity before the rot is even visible. This fungus can also reactivate if the wood becomes damp again. Damage can occur rapidly.
When inspecting for brown rot, look at the damaged portion to see if the wood is breaking up into little brown chunks. If you break out one of these chunks with a knife or screwdriver, it will appear similar to a small piece of charcoal – but it is brown in color.
What Does white rot damage look like?
Wood damaged by white rot will have a “bleached out” appearance. Use your knife or screwdriver to start picking away at this type of damage and you’ll see that the wood comes off in a “stringy” form and it looks similar to moistened “Shredded Wheat” cereal. White rot damaged wood will also have a “spongy” appearance because the infected wood members will literally start shriveling up like an “old kitchen sponge”. White rot will cause wood to become light in weight, soft, and very weak. Damage can occur rapidly.
What does poria incrassata damage look like?
This is a specialized brown rot fungus and it can be very destructive to structures. One of the reasons why this fungus is so destructive is because it produces roots (Rhizomorphs) which will supply water from a source that is 30 feet (or more) away from the active infestation.
When inspecting damage, you’ll see the same “cubical checking” as you would with brown rot. Look for fruiting bodies (similar to the head of a mushroom) that are brown to orange to purple in color. Some of these may be as large as a dinner plate.
If you suspect a problem with poria, we strongly recommend that you hire an expert who can find the roots, which are feeding this fungi, and eliminate them. Poria is like brown rot on “steroids”, and it will quickly destroy a home.
8 Tips To Help Prevent Dryrot
1. In areas where the decay hazard is high, it is best to use the heartwood of a decay-resistant species. Redwood and western red cedar are good choices. You may also want to have the wood treated with a good preservative.
2. When building a new home, always make sure your site is “well-drained”. You do not want water seeping under the house. Larger roof overhangs, rain gutters and downspouts can be very effective. Also, remember that you should never place untreated wood within 18 inches of the ground.
3. On homes with a raised foundation, make sure you have adequate cross ventilation. A good rule of thumb is to provide two square feet of opening for 25 feet of wall. Keep vegetation cut back away from subarea vents so they won’t restrict air flow.
4. In areas where you have soil with a high moisture content, install a moisture barrier on the soil surface. This will cause the moisture to condense on the bottom of the plastic barrier and return to the soil, instead of condensing on the floor and structural members of your home.
5. Don’t mount wood directly on concrete unless you are using treated wood. On items like patio or porch post, it is a very good idea to use metal or plastic spacers to keep wood up and off the concrete. This will help prevent the wood from “wicking up” water from rain or lawn sprinklers.
6. Control moisture. If you have plumbing leaks, roof leaks, sprinklers spraying against the house, or any other situation where wood is getting wet, have it fixed as soon as possible.
7. Repair or replace damaged wood because all of those cavities or holes caused by termites are easy places for moisture to collect and start dry rot.
8. Seal exterior wood with caulk and paint. This will help to keep moisture out. 
How To Repair Dry Rot
When doing repairs, always try and control the moisture source, first. If you don’t, the problem will simply continue. Minor dry rot damage can often be carved out, treated with a registered fungicide, and repaired with a quality wood filler.
Wood members which are heavily damaged should be cut out and replaced. You should always cut out damage at least one foot beyond the rotted areas. Some make the mistake of placing another piece of wood right along side of a dry rotted member so they can “brace it up”. Don’t do this, because the dry rot will quickly attack the new wood. The only exception to this rule is when you are working in an area where you can completely eliminate all moisture, such as in a wall or under a house. Remember that dry rot is like cancer, and it will quickly spread unless you can completely eliminate all of it.
Have a problem with dry rot damage on your home or business and need help in repairing it? Call our office at (949) 631-7348 and we’ll be happy to schedule an appointment at your convenience.
