PRELIMINARY DESIGN / BID PACKAGE
Once the basic foundations have been laid down in the concept design
phase, the next stage is to generate a more detailed set of design information.
Typically, this process would include some tuning of the conceptual work,
tow tank testing if appropriate, refinement of powering and weight calculations,
structural engineering, production of materials estimates and preliminary
intention of this phase is to take the project to the stage where it can
be offered to various yards in the form of ‘preliminary design / bid package’.
The selected yards are then invited to bid for the build project. The ‘preliminary
design / bid package’ generally includes outboard and inboard profile drawings,
interior and machinery layout drawings, a detailed preliminary specification,
which is usually referred to in any subsequent build contract, a detailed
weight study, preliminary structural and system drawings and a 3D computer
model of the hull and superstructure.
The preliminary specification for the vessel describes as many features
and components of the boat as possible. This document also includes
all requirements of the yard, including the need to implement specific
quality assurance procedures, weigh schedules for the vessel and warranty
The quantity and detail of the ‘preliminary design / bid package’ has
a direct correlation on the accuracy of the yard’s costing. There is a
balancing act between providing enough information for an accurate and
fair costing and completing the package at a reasonable cost to the client
before the final decision is made to proceed. The more work that is done
during this phase will reduce the amount to be done during the ‘detail
The design can still be completely or partially reviewed before going
to the ‘detail design’ phase and there
is often interaction between the designer, builder and client. This may
need to be done to bring the predicted build costs within the available
budget or to incorporate any additional requirements or ideas.
© Content Copyright 2007 - Craig Loomes Design