Wood Rot - a common problem
Wood rot is a common problem in boats and is often misunderstood as the name is very misleading.
Wood rot is caused by various fungus that will struggle to take hold in dry conditions. It needs two key ingredients to flourish; damp and food. Both of these are abundant in the bilges of many boats; it’s often damp and the floor bearers are made of tasty wood which fungus devours.
If you lift a carpet or lino and see the unmistakable veins of something spreading, then you already have a rotting fungus which needs treating. But if the floor suddenly goes underneath you, it’s gone a little far.
This is what happened to this boat; someone came out of the shower and the floor gave way. Key cause of the rot was a stupidly placed deck drain hose that allowed the under-floor area to fill with water and crud which, over time, built up a nice dam of crud and stopped the water from draining into the bilge, instead providing a feast for the rot fungus.
The whole rear cabin floor had to be replaced but the fungus had also made its way into the shower cubicle bulkhead which was laminated on both sides. We dug out as much of this rotten material as possible using specially modified tools and picks until we reached solid plywood again and then pumped in an epoxy resin filler mix to provide the strength again.
All the floor bearers, supports and boards were replaced, ensuring that every area of this new wood was first fully protected with a fungicide and then painted with bilge paint. We also lengthened and re-routed the deck drain to flow into the bilge to prevent a similar occurrence.