I-04 The Design Package

live equation

set values above to see the live calculation

Mu = Governing bending demand

Vu = Governing shear demand

DCR = Final utilization for each member

explained

The design package is the deliverable — plans, details, calculations, and specifications that tell the contractor exactly what to build. Every member size, connection detail, and load assumption must be documented. The framing plan is the roadmap; the calculations are the proof.

key concepts

overviewDrawings, calculations, and design criteria

A structural design isn't done until it's documented. The design package includes: (1) structural drawings — plans showing member sizes, connection details, foundation sizes, and notes; (2) a calculation package — showing load takedowns, member designs, connection designs, and code checks for every element; (3) a design criteria — summarizing codes used, loads assumed, materials specified, and design methodology. The drawings tell the builder what to build. The calculations prove it works. The criteria tells the next engineer what you assumed.

three documents, one packageDocumentation completes the design

A structural design isn't done when the last member is sized — it's done when it's documented. The design package has three parts: (1) Structural Drawings — plans and details that tell the contractor exactly what to build, (2) Calculation Package — the engineering work that proves every member and connection is adequate, and (3) Design Criteria — a summary of the codes, loads, materials, and assumptions that underpin the entire design.

who reads whatEach audience uses a different part of the package

Different people read different parts. The contractor reads the drawings — member sizes, connection details, reinforcing schedules, dimensions. The building official (plan reviewer) reads the calculations — checking that code requirements are met. The next engineer (future renovations, forensic investigation) reads the design criteria — to understand what was assumed and why. A good design package serves all three audiences clearly.

Test Your Understanding

1. What are the three main components of a structural design package?

Plans, elevations, and sections Drawings, calculations, and design criteria Loads, members, and connections

2. The calculation package exists primarily to:

Satisfy the building department Prove that every element can resist its demands, creating a reviewable record Show the architect the structure

3. Who is the "design criteria" section written for?

The construction contractor The building inspector only Any engineer who needs to understand the assumptions behind the design

The Design Package

lay out a building. count the pieces.

I-04 The Design Package