Essential tips for boat owners
For those unfamiliar with marine timber, wood rot can be a challenging topic. It has several causes and can be time-consuming and expensive to repair. If not repaired correctly, it can return, causing additional issues. Understanding and addressing this problem is crucial for maintaining your vessel.
How to identify wood rot
You can identify wood rot through a visual inspection. Look for dark discolouration on the timber. Probing with tools like a fingernail or a sharp tool can also help. Using a marine moisture meter on suspect areas is effective. Surveyors often use a small hammer in the ‘percussion method‘ to detect deteriorating or delaminated areas. Decaying wood may be hard, dry, spongy, watery, mushy, or slimy. Recognising these signs is the first step in managing the issue.
Wood rot causes
Rot develops when non-coated timber is in constant contact with moisture. Wood does not rot just because it is wet; it rots because ‘rot fungi’ thrive in these conditions. Fungi require moisture, oxygen, a stable temperature, and nourishment from wood fibres. Fungus spores are everywhere, carried by wind and rain. Once moisture is present, they begin to grow. Boats are particularly susceptible due to their damp environments. Understanding the causes helps in preventing its occurrence.
Wet vs. Dry Wood Rot
Wet rot occurs when unprotected timber is constantly wet. Dry rot happens when timber is repeatedly wetted and dried. Both types require attention to prevent damage.
Rot or mould?
Wood rot fungi penetrate and grow within the wood grains. Mould, a surface effect, does not penetrate the wood structure. Both live on plant matter and can become airborne. It is common to find both fungi in the same areas. Recognising the difference between these two issues is essential for proper treatment.
Wood rot prevention
Prevention involves ventilation, cleanliness, coatings, and regular maintenance. Keep your vessel well-ventilated with fans, dehumidifiers, and natural airflow. Avoid shrink wrapping your vessel; use tarps instead. Keep your vessel clean, dry up moisture, and use mould cleaners to prevent build-up. Ensure all timber is coated or treated with paint, varnish, oil, or preventatives. Prevention is easier than dealing with its consequences.
Addressing wood rot on your vessel
If you find rot on your vessel, the only cure is to cut it out and replace it with new timber. Treat surrounding areas with a fungicide before replacing the timber. Your shipwright or yacht carpenter should replace sections to marine standards, maintaining the strength of the damaged area. Properly addressing the issue is crucial for the integrity of your vessel.
Debated or controversial repair methods
Some products claim to restore rotten timber, but wood fibres cannot be rejuvenated. Filling voids with polyester, epoxy resins, glass, or bog is not a solution. These chemicals need a sound base to adhere to. Incomplete removal of fungi will result in recurrence. Always remove and replace rotten wood to ensure a lasting repair. We always advise our clients to avoid quick fixes; they can lead to more significant problems.
Hire an experienced shipwright
When faced with rot, hire an experienced shipwright. Proper repairs are inconvenient and expensive but necessary. Doing it right the first time saves time and money in the long run.
Safety considerations
Working with fungicides and other chemicals involves risks. Protect yourself by using appropriate masks and ensuring ventilation. Awareness of the dangers of inhaling wood rot or mould fungi spores is crucial.
