Hull Deck Seam

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I was asked to share my experience in re-doing the hull-deck seam


We recently took on the project of re-sealing the deck to the hull and varnishing the toe rail. The bedding compound had become nothing more than a sieve for the sea water that came into the boat. There is much information on this site that I used and it helped me extremely! I will try and document my steps that may fill in some gaps to this information. I will use bullet points, hopefully in order, so that I can come back and add new points as I remember them.

I would say that this is a 3 out of 5 on the difficult level and most people should be able to make this repair in 2-3 weeks with daily work. But do not ignore when the wine or beer light comes on in the afternoon.


  • First, take pictures of everything. When you think you have enough, take some more. We are no longer in the world of film, so taking a hundred pictures, it costs nothing, but a single picture may become invaluable a month or year into the project.
  • Get a big screw driver, 18-24” long. Make sure the shank is square so you can put a large wrench on it for those hard to get out screws.
  • Remove all the hardware that is mounted on the toe rail. The jib sail track has lots of screws. (I buy expresso coffee by the case and have lots of cans. I label each can for the screws and where they came from). This is a two-person job since these are held down with nuts.
  • My teak toe rail came up easy, again there was not much bedding left and 5200 had not been used. You can label these, but when you put them back together, it is obvious what goes where. We did have to do some repairs and had to build up areas with epoxy.
  • Then there are the screws holding the deck to the hull. This is another two-person job. There is no rhyme or reason whether there are wood screws or nuts and bolts used in fastening the deck to the hull. This is where the large screw driver comes in handy. Remove the screws from one side of the boat only. Removing both sides may deform the hull.
  • You may find some of the screws are bent. When I found these, it really pissed me off why someone would put in a bent screw. But I later realized that with all the screws coming down for the seam, the toe rail and the jib track, some were right next to each other. The only way to tighten the nut next to a screw was to take the box end of a wrench and bend the screw, to give you enough room to get a wrench on a nut and tighten it.
  • While the toe rail was off, I removed the stanchions for the lifelines and re-bedded them with butyl. I also sanded the deck and the lip that goes up to and under the toe rail in preparation for painting, later plus having a clean surface for the toe rail to attach.
  • Now comes the fun part, separating the deck from the hull and removing the old bedding compound. I divided the boat into four quadrants and started on the side that I had removed the screws. (I did all this work while the boat was still in the slip.) At the midship, there are scuppers on each side. These are the only points where the deck and hull are attached by fiberglass. Mine were cracked and I repaired them during this process.
  • In trying to come up with a way to clean all the old bedding, I discovered a new tool, to me. An Oscillating Multi-Tool. I chose a Dewalt 20 volt cordless one and it turned out to be the best thing since sliced bread! Someone said to me, whoever invented it, shouldn’t have to work another day for the rest of their life. It has a cutting tool that cuts the old bedding out. It comes with a sanding pad to reach in and sand the surface. I don’t know how I would have cleaned these surfaces without this tool. I also purchased composite shims from Home Depot and shoved them in every foot or so, using a catspaw to slowly raise up the deck, as I worked down the seam. At the end, I folded sandpaper over a shim to reach difficult locations and then wrapped a cloth, soaked in acetone over the shim to clean the inside surfaces.
  • When one quadrant was completely cleaned, it was ready to assemble. The hull part was offset about a half an inch from the deck overhang. I ran blue 3M tape to cover that half an inch so the calking would be easy to clean up afterwards. I used 5200 slow cure to join the joint. I know there is some debate on this but I did not want to do the repair again. I shot the calking into the gap, but did not fill it completely. As I moved down, I pulled the shims out, until one quadrant was done. I then came back and replaced all the screws. The calking oozed out and I ran my finger along the edge and made sure the calking had spread evenly. The following day I did a final tightening of the screws. After completing the two quadrants on the starboard side, I turned to boat around in the slip and did the port side and the transom.
  • After the toe rail was varnished, I bedded it with 4200 and finished off the inside and outside edge with my finger.
  • Finally, I bedded the Jib track with butyl tape.
  • After going through this process, I realized I had compromised the bedding for the chain plates. I had new ones made and replaced them.

I hope this will help those who take on this task next. It is not the end all but only one person’s experience. Everyone will come up with different issues and new solutions. Because, as we all know, there is no one single project on a boat but the beginning of a new rabbit hole that takes us on a new journey.

I am happy to say that we did the Baja Ha-Ha and the Baja bash after this repair and had no leaks! We did have some leaks from the windows…thus this summer’s project.

Here are some videos.


Best Regards,


Dennis Franklin Patterson

SV/ Wind Horse