Log Home Tips & News

Protect Your Log Home from Fungi

by | Log Home Maintenance

Each year more wood is destroyed by decay than by all fires, floods and termites combined. The secret log home destroyer and the ultimate master of disguise is fungus! Fungi are responsible for a majority of rotten logs on log homes. In favorable environmental conditions, fungi will essentially eat the wood of your home, leading to decay and rot.  Fungi use a straw-like structure called hyphae to release digestive enzymes into their environment that break down wood so that the fungi can readily absorb the nutrients from the wood, causing rotten logs.

The types of wood destroying fungi encountered by pest management professionals and homeowners fall into two basic categories: brown rot and white rot. White rot attacks the cellulose and lignin in the wood giving the wood an off-white appearance. In the later stages the wood becomes spongy to the touch. White rot typically attacks hardwoods and lacks the cubical checking appearance of brown-rotted wood.

The Perfect Conditions for Log Rot

Wood destroying fungi need three things to survive, air, water, and food. Since we can’t eliminate air and their food is the wood in our homes, the only mechanical control mechanism available to us is the elimination of water. Many people erroneously believe that water causes rotting logs, but it is actual its microorganisms that cause the destruction.

There are certain conditions that are conducive to wood rot and decay in your log home. These requirements are:

  • Warm Temperatures

Wood rot more in the warmer months because the microorganisms responsible for log rot thrive in temperatures greater than 60 degrees.

  • Water

According to the United State Department of Agriculture (USDA), fungi thrive in environments with at least 20% moisture.  This is higher than the recommended moisture content of logs in log homes.

  • Air

Fungi are aerobic organisms that require oxygen to function.  Oxygen is essential for the fungi to begin the process of log decomposition.

  • Food

The cellulose and lignin, which are carbohydrates found in logs are perfect gorging material for fungi.

Prevention of Decay Fungi

Eliminating environmental conditions suitable for fungi growth and more so some type of moisture control should be an integral part of preventing decay fungi rotting logs. Here are a few tips to start:

  • Clean gutters and downspouts, which are a breeding ground for log rot, and make them free of debris.
  • No wood should ever be in contact with the ground. Wood posts, piers, supports, etc. should always rest on concrete footers raised above the level of the surrounding soil. Logs should be at least 2 feet away from the soil.
  • Protect your logs by keeping your exterior stain and topcoat in good condition. Exterior wood should be coated with a water repellent stain.
  • Moisture can seep through cracks or areas of impaired adhesion in chinking and caulking.
  • Basements should be waterproof and equipped with a floor drain. If the relative humidity in the basement exceeds 50%, a dehumidifier should be installed.
  • Roof leaks should be fixed. Large roof overhangs can help shield the logs below from exposure to precipitation.
  • An interior pipe burst or other plumbing leaks should be repaired as soon as they are noticed.

Chemical Control Methods

Borates are used for treating wood for decay fungi including brown and white rot. Brown rot commonly attacks softwoods turning the wood dark brown. Once brown rot has extracted all of the nutrients from the wood the wood may become dry and powdery. This leaves the impression that dry wood has rotted but in reality it is an old infestation of brown rot.

  • Remove any insulation in a crawl space that may be present between the floor joists before you begin and check the entire area with a moisture meter.
  • If there are any sections of wood where the moisture content is 20% or above, a preventative treatment is recommended. An application of borate wood preservative, which controls both insects and fungi, finished with some type of exterior sealer is all that is generally needed.
  • After treatment, make sure all crawl space vents are open and, if necessary, install temporary fans to help dry the wood before replacing the insulation.
  • Within a few days after a treatment has been completed the fungi will begin to die and dry up. Occasionally the dead fungi will emit an unpleasant odor as it decomposes. This odor will only last a couple of days and may be minimized with the circulation of fresh air into the treated area.

Following these tips and regular log home maintenance will help reduce the occurrence of rotten logs.  If you notice some questionable areas of log rot or think that you have a moisture problem, get in touch with your local log home maintenance experts, before it turns catastrophic.

Our professionals at Performance Log Finishers are skilled at diagnosing log rot and fixing related problems.  Contact us today! Call us at (800) 781-2551.We would be happy to come out and inspect your home for log rot and offer viable options to remedy the situation.

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