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Dry Rot: How It Affects Roofing Systems

There are many reasons you should keep a regular maintenance routine for your roof. One of them is to make sure that it doesn’t succumb to dry rot. In this blog, roofing contractor State Roofing discusses how dry rot develops on roofs and how you can prevent it from damaging yours.

How It Affects Roofing Systems

What Is Dry Rot?

Dry rot is a type of deterioration caused by fungi, the most known species of which is Serpula lacrymans. Other known species that cause dry rot include Coniophora puteana (cellar fungus) and Poria vaillantii (pore or mine fungus). Unlike wood rot caused by moisture alone, dry rot can occur in environments with minimal amounts of moisture, hence the term “dry rot”. As fungi “blossoms” on wood, it sends out microscopic strands, which split wood fibers and eventually turn the wood soft.

A typical roofing structure is mostly made of wood, including critical components such as support beams and rafters. The decking material is made of processed wood. Even roofing materials such as cedar shakes and “organic” asphalt shingles are made of wood or contain wood fiber. If dry rot were to occur on these components—particularly in structural components—it could lead to collapse or permanent damage.

Signs of Dry Rot

To inspect your roof for dry rot, you will need to climb into your attic. Bring a flashlight and an elongated tool such as a screwdriver. Wear gloves and do not handle fungi with your bare hands. Wood rot has visual cues you should keep an eye out on, particularly a distinct white growth on bare wood. Other visual signs include fragmenting and cracking. When you tap the wood with a screwdriver, pieces will fall off. Rotten parts of the wood can be removed with your fingers without effort.

How to Prevent Wood Rot

Fungi thrive in areas with high moisture levels and not necessarily on wet surfaces. Roof leaks need to be repaired, of course, but you should also address the attic humidity levels. If the attic feels too warm, and you don’t feel any air movement as you near the soffits, your roof isn’t getting enough ventilation. If roof ridge vents are not adequate for ventilation, consider having roof ventilation fans installed. If roof rot is already underway, consult a roofing contractor soon, as dry rot quickly spreads.

State Roofing is the area’s leading provider of roof repair and installation services. Give us a call at [company_phone] or fill out our contact form. We serve customers in Seattle, Bothell and Everett, WA.

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