top of page

TPYD Design Process

Updated: Nov 22, 2023

The engineering design process, also known as the engineering method, is a common series of steps that engineers use in creating functional products and processes. The process is highly iterative – parts of the process often need to be repeated many times before another can be entered – though the part(s) that get iterated and the number of such cycles in any given project may vary.

("Criteria for Accrediting Engineering Programs, 2019 – 2020". ABET. Retrieved 15 September 2019.)

In order to successfully create functional product (in our case boat design) many different activities need to be carried out (and repeated if needed) in different stages of design process, keeping the creativity active, fulfilling client wishes and complying with required standards at the same time. Sometimes many of this requirements can be very conflicting and opposite. Designer's job is to carry out design process using different design methods and tools to reconcile all mentioned demands and finally bring out functional design or product. In the whole process knowledge and skills in both yacht design and naval architecture must be combined together to result in esthetically appealing and technically functional design.

Design process is usually divided in several stages, each having it's own significance in the whole product. In general, boat design and building process can be divided in following stages:


Design process - Graphic presentation of major design phases with corresponding activities


Initial Design

First stage starts with future client contacting design studio. Although not necessarily always the case, client at this stage already have general vision of her/his future yacht/boat. In most cases, vision is complication of different design features and solutions client have seen on different similar project. In case there is unique solution or detail, some sketches are usually what client already have prepared on their own. In communication with client designer usually tries to put all the features and solutions together in one "picture" in a way that all work together. All of these activities result in a document called "Design Brief". It is usually document consisting of one to five pages, giving rough guidelines and notes on how to proceed with the project.

Many times similar projects are further investigated and new features are discovered in more details and implemented in new design, pushing the design to grow and develop. Similar project are translated into numbers and mathematic expressions and serve the designer as a basis for technical foundations of new project. At the same time, based on the previously agreed Design Brief, designer runs his own "theoretical" calculation of main technical properties of the vessel.

As an end result of this stage, document called "Design Specification" is generated and confirmed by both client and designer. This document usually consists of five to fifteen pages containing more detailed descriptions, features and equipment lists. Sometimes some rough layouts and profile designs are included.

Basic Design

This is the most creative but also the most responsible and most demanding stage of design. During this stage, going through several circles on design spiral, and implementing designers experience on previous projects, most design and technical properties of new design are defined. First 3D models are generated and spaces and ergonomics defined. At every turn of design spiral, technical aspects (like stability, visibility etc.) are investigated and evaluated. Experienced naval architects and designer already implement earlier gained experience and knowledge of class requirements. All big changes MUST take place in this stage because coming back to this stage from later stages of design process would require repeating all the steps in between.

Final result of this stage is rough 3D model (including hull, deck, superstructure and interior flooring surfaces) with most big systems included (engines, tanks, generators, gyro stabilizers, etc.). At final circle on design spiral, load case is defined using concept 3D model. Resulting mass and center of gravity (CG) position are used in rough stability, hydrodynamics and scantlings analysis.


Influence-Cost Curve - Presents influence, cost and possibilities of potential decisions in different stages of design process


Preliminary Design

Preliminary design stage involves future developments of concepts defined in Basic Design stage. All outer surfaces get more styling details, hull is upgraded with appendages design, scantlings get confirmed by calculations, systems are designed and calculated in further details, interior gets colours and materials, functional design is further developed and ergonomics are analyzed in finer details.

At this stage boat is designed with all functional and esthetical properties. All the calculations are carried out in details to confirm the compliance with basic calculations. Most of this calculations will be part documentation supplied to client and the end of next stage - Contract Stage.

Contract Design

Contract design stage should result in set of documents defining the new design in such a level of details that classification society or certification body can evaluate compliance of the design with rules or standards. Such documentation is usually sufficient for experienced boat builder to build the boat without any other inputs from designer or detailed engineering office.

As mentioned earlier, this set of documents include calculations and reports required by standards and rules. This documentations usually includes: Detailed general arrangement, scantlings calculations and drawings, stability calculations, cockpit drainage calculations, man-over board prevention plans, fire fighting and escape plans, mooring and anchoring equipment calculations and plans, systems calculations and plans, electric systems schematics etc.


Design spiral - method most commonly used in naval architecture to cope with iterative nature of design variables


Detailed Design

This is final stage of design where all the finest details are defined, and today most often modeled in 3D. All surfaces becomes A class, mold surfaces are generated, cutting plans are defined, laminate plans get all the metal bracings for equipment installation, systems is modeled with all the piping and electrical systems are further on extended with wiring plans and boundless. All the parts of boat are engineered to be ready for preparation of workshop documentation that is provided in next design stage. Bill of materials list (BoM list) is defined.

Production Support

In this stage all the workshop documents are generated including detailed laminate plans with technology instructions, CNC cutting files etc. Production tooling are engineered (like mold structures and assembly tools) and production process is designed in order to optimize production process and minimize production time. In serial production methods and systems like Just in time or Kaizen are implemented.


From everything presented above it is to conclude that, because of complexity of boat design project, systematic and organized design process is required. In order to make it more organized and to be able to foresee the outcome, we apply basic engineering principle to divide the project into smaller design stages and problems, solve them separately, and then put them all together to analyze their mutual impact and influence on final result.

Although it is not the only design method used it yacht and boat design, in practice it is proven to be very efficient if applied correctly and with understanding.

If you have any additional questions regarding our design process, this article or you would like us to help you implement mentioned design process into your next project, please do not hesitate to write us at


Commenting has been turned off.
bottom of page