Designs for boat cockpit enclosures are even more varied than boats. It seems every boat owner uses their cockpit in a different way, and has different priorities. We recently replaced out canvas with a stock dodger from the boat's manufacturer, added a few tweaks of our own, and ended up with something we are very happy with.
Our design brief for Harmonie's dodger calls for reasonable protection from sun and rain, while also being fully, easily, and quickly foldable. We fold down the dodger when we are in close quarters and docking to give unobstructed 360 degree view to the person at the helm. The dodger is folded down when we are anchoring to allow easy communication between the helm and the foredeck. We also fold it down when sailing offshore at night in benign conditions just to enjoy the stars. We only use the side panels in rough weather or if we expect rain. The panel across the cockpit is only used in cold weather, or if we are sailing downwind in rain.
Building a complex piece of canvas work like a dodger is expensive. It is very labor intensive, especially the design and fitting. Several trips from the workshop to the boat are usually required to get everything "just right." We decided to work around this by going to the source. Chantier Amel the French manufacturer of our boat quoted us a very reasonable price for a new dodger. Not totally surprising since they have the exact plans to build what will fit, and all of the design work is already paid for. Knowing that we'd surely have a few tweaks we'd have to make ourselves, we placed the order.
Like many things from Amel, the dodger was first class. It was made of heavy duty vinyl, not a woven fabric. Almost all of the seams were welded, not sewn. 100% waterproof. Our old dodger dripped, right on the head of the person sitting at the helm from the needle holes in a stitched seam. The new dodger fit in such a was that it gave an extra few centimeters of head room underneath. It fit perfectly. It wasn't, however, (yet) completely perfect.
The fabric tubes that accepted the metal arch tubes had no zippers. This meant the arch tubes needed to be removed from the boat and VERY CAREFULLY guided through the fabric tubes. After doing this twice, we decided that adding zippers was an excellent idea.
The various side and back panels from our old unit were in good shape, and we kept them. The zippers between the new and the old didn't all line up exactly, so we needed to shift them a bit. We ended up with a better fitting system all together.
We also added forward facing, opening windows to add to ventilation and visibility. It came from Amel with a window installed over the helm station to see the sails. This window has a sun cover that velcos in place. This is very helpful. We made no changes here, but we do wish the window was a bit bigger, and that the sun cover was on the INSIDE. The velco used to attach it I expect to have very short lifespan in the sun. But it is easily replaced.