Stop water finding its way in through a cracked coachroof
Coachroofs combine fibreglass, wood, and metal fittings that all expand and contract at different rates, opening hairline gaps along the joints and seams where water can track in. Captain Tolley’s Creeping Crack Cure uses capillary action to seep into these gaps and seal them from the inside, without needing to strip back or rebed the surrounding structure.
Over time this loosens the fitting and opens fine cracks around its base, often invisible until water starts appearing below.
Captain Tolley’s Creeping Crack Cure uses capillary action to seep into these hairline cracks and seal them from the inside, without needing to remove or rebed the fitting.
“Put a huge effort into scraping back, gap filling with everything from CREps to linseed oil and putty without success. A few treatments with this and so far all good. This was on varnished teak join between doghouse and coach roof.”
– Simon Cormack, Judge.me review
*For best results, apply in dry conditions above 10°C / 50°F and keep the area dry while it cures. Cold or damp weather slows curing, and moisture can dilute the sealant before it sets, so allow extra time if conditions aren’t ideal.
Yes – that’s exactly the kind of gap it’s designed for. Where fibreglass, wood, and metal fittings meet, they expand and contract at slightly different rates, and it’s this constant tiny movement that opens the crack in the first place. The sealant flexes with the joint once cured rather than needing the materials to stay perfectly still.
Coachroof seams often sit where several materials and layers overlap, so the path water is taking can run further than the visible crack suggests. If it doesn’t seal on the first try, that’s usually why – simply reapply, and most joints are fully sealed within several applications.
Let it cure fully before exposing it to water – applying it just before rain or in damp conditions can wash it out before it sets.
Deck fittings - chain plates, stanchion bases, cleats, winches, handrails, and deck fill pipes - are constantly stressed by rigging loads and movement underway, which loosens them and opens hairline cracks for water to enter the boat.
In bad weather the cockpit can suffer leaks caused by fine cracks, particularly around the entrance to the cabin.
Wooden decks, teak trim, and the joints between planks suffer the extremes of sun and rain, which opens hairline cracks along seams, caulking lines, and where the wood meets fibreglass or fittings.
Deterioration of the seal between the frame and boat structure is a very common cause of leaks from hairline cracks in boats.
