DIY Fiberglass Composite Pilothouse Construction

Building a custom fiberglass composite pilothouse allows an older sailboat or powerboat to be transformed without relying on traditional plywood construction. These projects show how I use Coosa Board, epoxy and fiberglass to design and fabricate lightweight, waterproof pilothouse structures, including bulkheads, roofs, window openings and curved surfaces. The result combines composite boat-building techniques with practical DIY fabrication to create a strong, rot-resistant pilothouse specifically fitted to the existing hull.

Make it look like it came from the factory.

A DIY fiberglass composite pilothouse can add weather protection and usable interior space to a small sailboat or powerboat without the weight and rot concerns of traditional plywood construction. This project uses Coosa Board, epoxy and fiberglass to fabricate a lightweight custom pilothouse designed to follow the existing lines and deck camber of the boat.

Construction begins with full-size patterns and mockups before the composite panels are cut and assembled. The structure is shaped on the boat, the joints are reinforced with epoxy and fiberglass tabbing, and a mounting flange allows the completed pilothouse to be secured to the existing cabin top. Window openings, roof construction, finishing and final installation complete the conversion.

The complete step-by-step process is available in the MotorCity Boat Werks Technical Library. Watch the video below for detailed project steps and solutions.

Compac 16 Pilothouse Conversion

This project transforms a 1983 Compac 16 sailboat into a pilothouse sailboat using lightweight composite construction. The pilothouse is built primarily from Coosa Board, with Coroplast patterns used to establish the shape before fabrication. The structure is assembled using epoxy, fiberglass reinforcement and composite construction techniques, then fitted with plexiglass windows and a repurposed original companionway hatch. The conversion increases usable cabin space and weather protection while keeping the pilothouse relatively lightweight.

The complete step-by-step process is available in the MotorCity Boat Werks Technical Library. Watch the video below for detailed project steps and solutions.

Don’t Go It Alone. Join the Werkers

Get access to all my tips and tricks, behind-the-scenes-content, and technical Library.

Join the Werkers on Patreon