What is the issue?
Spray hoods become slightly porous after four or five years of constant sunshine. Once this happens they loose their waterproofing capability.
Why address this?
At first small pools of water that can stand in the middle of the spray hood start to drip down into the companionway. Over time it becomes increasingly wet beneath the spray hood as a whole so nothing can be protected that is left there.
How to address this?
Spray or paint the hood with a clear water resistant silicone solution available from most hardware shops.
Silicon forms a colourless, non-staining film which protects and waterproofs the spray hood. An annual touch up of this very inexpensive spray made our spray hood serviceable for many years beyond where I would have naturally replaced it. In addition silicon is very versatile on a vessel and can also be used to renovate plastic, rubber and wooden surfaces and protect and lubricate locks, switches, latches, hinges zips etc. So it is more than convenient aboard.
It is however slippery and should not be used on decking. Paintwork should also be avoided as it tends to bond very efficiently with paint making it difficult to clean and resurface in the future.
Michael Harpur, Yacht Obsession with thanks to Mark Beasly