Joiner Bulkhead Construction Details

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The drawing below shows the key details for a typical joiner bulkhead intersection along with furring on a fiberglass bulkhead. There are several different materials used in this construction, each picked for a specific purpose. Not shown is the insulation which would go in the spaces between the studs. This would normally be 2” thick rigid fiberglass, or for better sound control 2 layers of 1” fiberglass with sheet lead sandwiched between. In either case fitting the material tight to the inside of each cavity is critical, gaps allow more sound to come through.

bulkhead section view

section view from above

The bulkheads will be built on a bench without the veneer panels then installed in sections on the boat. The wire chases, pull-wires, outlet and switch box cutouts should be done while being assembled as should the insulation be installed.

The materials used are as  follows:

  1. studs  & framing: Meranti
  2. sub panel (first layer) of plywood: 6mm  6566 Aquatek
  3. custom layup veneer face plywood  on 6mm  balanced 5 ply core
  4. epoxy: System3 general purpose and Gell-Magic
  5. Sikaflex  291
  6. Titebond II woodworking glue.

corner joinery detail & adhesives

The  drawing to the right shows which adhesives are used where and how the veneer faced panels come together. The bulkhead section is glued to the keys with epoxy, this gives a rock solid joint with some gap filling properties and will allow for a small amount of flex without cracking. We use Sikaflex between the sub panels and the studs as it is strong yet flexible which in this case works well to minimize vibration and sound transfer through the wood. The Paneling is glued to the sub panel with thickened epoxy, this holds extremely well and does not allow  for any significant movement. The joints, veneer panel to veneer panel are glued with Titebond II. This makes a clean, crisp glue joint, that with the epoxy behind and and construction as shown, I’ve not seen fail. This construction takes a high degree of skill and planning, but is about the only way I know that makes seamless joints for the long term.  Epoxy though strong and bonds exceptionally well with wood needs a thick glue line, therefor makes an unattractive joint.

The corners are the other structure I would like to look at here.  The drawing below shows how the corner post fits and how the panels come together. The corner post shown has about a 2 inch radius and is a fairly large soft round corner. The overall size and detail of the post can be changed to match individual tastes. Note how the rabbeted joint under the small  radius corners lips over the veneer faced panels. Any difference in the seasonal movement between the plywood and the solid wood will not be noticeable. If the solid wood and the panel were flush it is likely a small, but noticeable crack will appear within a year or two. The hidden part of the joint would be glued with Gell-Magic while the visible part  with Titebond II for a crisp joint.

section view at corner post


This is a brief overview of  bulkhead construction, there are many more details and considerations. The overall system is designed to give consistent results, solid joinery, be efficient and  is self squaring, plumbing and leveling.





  1. Really impressed with the images in there expanded view, slick transition from small to large. Also The text complimented with the drawings give you a very clear understanding of what your explaining. Nice work.

    • Thank you Robbie, It is slowly getting there. I think that the transitions are a big improvement also. I think it would be hard to explain most of what I want to cover without drawing, I’m glad you find them clear.


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