The Strongal construction process was developed in 1975 by Michel Joubert (Sila Inua's architect) and Joseph Fricaud. The process involves the welding together of very thick marine aluminum plates, within the elasticity limit of the metal. The result is an almost frameless construction. The advantages of this construction process for Sila Inua are:
- superior hull strength, with greater resistance to impact and extended life
- high intensity welding results in excellent metal fusion and waterproofing
- minimal vibration from the engines and less stress on the metal
- greater flexibility in interior design, more space available
- minimal thermal bridging
- faster construction
Joseph Fricaud dedicated his family's boatbuilding facility in France to develop a niche market; long range sailboats for world travelers. The same construction process proved to be very suitable for small work boats. The process is now free of patent and could find other applications.
Information about the construction process is not widely available but here is a commercial link for pleasure boat applications. There is one shipyard, in eastern Canada, which has a license to the process. Here a link to them.