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Roof decking or sheathing refers to the thin boards of wood that span the trusses and support the rest of the roof. If your roof decking gets wet, it can develop wood rot and impact the performance of your whole roof. This problem can go unnoticed, as damaged roof decking hides beneath shingles and above the attic insulation. Sheathing isn’t normally visible, so it can be challenging for homeowners to find this problem before it becomes serious. However, you can easily avoid this problem if you know when to look for wood rot on your roof decking, how to identify the problem and how to fix it. This guide will tell you what you need to know to protect your roof and your home from wood rot.
Most roof decking, also called sheathing, is plywood or oriented strand board (OSB). These thin sheets of wood absorb moisture when exposed to it through excess condensation or a roof leak. When sheathing is exposed to moisture frequently, there is always a chance it will decay or develop wood rot. While a single exposure to moisture is unlikely to lead to rot, routine water exposure may.
If your decking is rotting, it may or may not have developed a fungal growth that can ruin its stability by eating away at it. Whether or not there is a fungus, or just normal decay of wood due to moisture, rotting roof decking can cause several problems for your roof and your home, including:
There are two main types of wood rot: dry rot and wet rot. There are also several subspecies of wood rot fungus. Therefore, every wood rot infestation may look different. Wet wood rot tends to look discolored or darker than the roof around it. Dry wood rot tends to look like a fungal growth, and it makes the wood cracked and dry.
Here are some more signs to help you identify wood rot in your roof:
An experienced roofer may suspect wood rot simply by stepping on the shingles above the rot and feeling it give more than normal.
Signs of dry wood rot include:
Tearing up a few shingles to look at the decking isn’t a normal home maintenance practice that you’d do on a monthly or yearly basis. You should look for wood rot either when you don’t know the condition of the deck (as in, you’re buying a new home) or when you suspect that moisture may have penetrated to the roof deck. You should ask a professional home inspector or roofer to check your decking for wood rot when:
If your roofer has reason to suspect that your roof decking may not be in good condition, they may recommend you let them look at it. They may not have to remove shingles to do so. Instead, they may be able to spot the signs of decking rot from inside the attic.
Leaks and condensation are the two most common causes of a rotting wood deck. It makes sense to look for deck rot around notorious leak points, such as skylights, roof penetrations and anchor points for roof-mounted items. In order to fix the problem, you first need a professional roofer to resolve the underlying leak.
Once your professional roofers have fixed the underlying cause of the moisture, they will need to replace all the wood affected by the dry or wet rot. Here are the tools and materials they will use and a step-by-step guide on how they will complete the job.
Tools and Materials Required
Here are the tools and materials your roofers will need:
Homeowners may be concerned if they discover that although decking is routinely replaced as part of roof repair, the decking on their roof wasn’t. This may be a cause for concern, or it may not. Not all wet decking needs to be replaced. If only a small area of the decking was exposed to water, and it wasn’t exposed long enough to damage it significantly, your roofer may choose to leave it in place. However, your roofers may have also made a mistake by leaving behind decking that did need to be replaced. To start, ask your roofer why they chose not to replace your decking. If you’re not satisfied with their answer, reach out to another roofer for a second opinion.
Are you concerned that your roof deck may have wood rot? Getting a handle on it as soon as possible is best to protect the rest of your home. Reach out to a professional today through IKO’s Contractor Locator.
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