wood useHistory has shown that, with proper design and maintenance, wood structures can deliver decades and, in fact, centuries of reliable service. The key is careful planning and understanding of environmental loads and other external factors likely to impact a building over its lifetime, which involves four main methods of control:

  • Moisture control – The design of durable structures begins with an understanding of moisture loading and how it interacts with building materials. Designers must consider sources of water, how the water is transported, and how to control and remove it. Wood construction maintained at a moisture content of 20 percent or less will not decay, and decay doesn’t generally occur until the moisture content reaches 25 percent or more. When wood is protected from water or vapor condensation, and exposed to normal atmospheric conditions, its moisture content rarely exceeds 15 percent. So controlling moisture is a simple and practical way to protect against decay.
  • Termite control – Moisture control also contributes to the prevention of subterranean termite attack, since termites thrive on water. Other methods include the use of barriers and bait systems supplemented by periodic inspection, which also protect against other insects.
  • Use of durable materials – In some cases, architectural considerations or use exposures (e.g. ground contact or certain climatic conditions) may necessitate greater protection. Under these circumstances, naturally durable wood species or pressure treated wood may be required.
  • Quality assurance – Where moisture and/or insects are an issue, quality control is especially important in constructing building assemblies to resist negative effects. Proper maintenance to keep the structure dry will also help to ensure its longevity.

The publications listed below include detailed recommendations for preventing damage from moisture and living organisms. The bottom line: wood frame structures, when designed correctly and properly maintained, can provide a long and useful service life equivalent to other common building construction materials.


More Information

General Durability

Moisture Control

Termite Control