1. Chapter 23: Structural Drafting
Structural engineering is generally associated with commercial steel and concrete buildings, and in some situations, it is also used for the structural design of residential buildings

2. Structural Drawings
Structural drafting techniques are generally the same as mechanical drafting; usually they are a combination of mechanical and architectural methods used
Structural drawings are usually independent of architectural drawings and other drawings

3. Line work Lines used in structural drafting are generally the same as those used in mechanical drafting
Lines may heavier or thinner than normal depending on the emphasis & size of the drawing
Dimension lines may be drawn with a space for the numeral or the numeral may be placed above the dimension line
Dimension lines may be capped with arrowheads, slashes, or dots

4. Lettering
Structural lettering is generally slanted gothic style and freer in style than mechanical lettering
Lettering heights:
All lettering, except titles: 1/8” to 5/32” (3-4mm)
Titles: 3/16” to ¼” (5-6 mm)

5. Coordination of Working Drawings
The structural drawings are a portion of a complete set of working drawings
A page numbering system is used in order to organization each type of drawing on a commercial project (AIA Handbook of Professional Practices)
The structural drawings can have a series of sheets that are numbered such as: S1.1, S1.2 – S2.1, S2.2, S2.3 – S3.1,S3.2, S3.3 etc.

6. Example of How Drawing Elements Are Coordinated Between Pages

7. Laying out Details and Sections
Details & sections may be placed with the drawing where they relate or placed on a separate sheet.
All Details should be grouped together and organized from left to right,and laid out in sequential order on the drawing sheet.
Sections are laid out in the same manner with labels in alphabetical order.

8. Concrete Construction Concrete is a mixture of Portland cement, sand, gravel, and water.
Concrete is the fundamental material for foundations
Concrete is used in commercial sites for wall and floor systems
Concrete can be poured or pre-formed into structural shapes

9. Steel Reinforcing of Concrete Concrete alone has excellent compression qualities but add steel and the tension properties improve to make it stronger
Reinforced Concrete: Concrete poured around steel bars placed in the forms
Rebar: The steel bars
The most common steel reinforcing is plane and deformed, in round or square bars

10. Examples of Standard Structural Callouts for Concrete Reinforcing
Specifying Anchor Bolts
(12)-3/4”ØX12”STD AB 24” OC W/3”PROJ
Specifying Rebar
HORIZ. AND 16” O.C.
VERT
WAY (or EW)

11. Types of Concrete Construction
Poured-in-place concrete
Pre-cast Concrete
Tilt-up Pre-cast Concrete
Concrete Block Construction

12. Concrete Structural Drawings
Concrete material symbols are used where appropriate
Rebar is shown as a very thick line or a thick dashed line in the longitudinal view and a round dot where the rebar appears cut
When drawing concrete block structures details of the steel reinforcing patterns are shown

13. Wood Construction Used in both residential and commercial applications
Commercial applications include:
Partition Framing
Upper-level Floor Framing
Roof Framing

14. Types of Wood Construction
Heavy Timber Construction
Laminated Beam Construction
Note: The drafter’s major responsibility is the drawing of the connection details for Heavy Timber Construction and Laminated Beams

15. Engineered Wood Products
I-Joists
Laminated Veneer Lumber
Rim Board
Plywood Lumber Beams
Stressed Skin Panels

16. Standard Wood Structural Callouts
Give the nominal (rough, before planning) cross-sectional dimensions for sawn lumber & timbers
4x12,6x14
Net dimensions of a glu-lam is followed by and abbreviation
6 1/8x 14GLB f2400
If lengths (LG) is required for wood members, they are given in feet & inches
6 ¾ x 18GLB x 24’-0” LG
Glu-lam beams with manufacturing numbers
6 ¾ x 18 22FV4

17. Steel Construction Three Categories: Steel Studs
Prefabricated Steel Structures
Steel-framed Structures

18. Structural Systems The structural system is made up of the frame that support the walls and roof.
Wall System – Horizontal Girts attached to the vertical structure and metal wall sheets attached to the girts.
Roof System – Horizontal Purlins attached to the structure and metal sheets attached to the Purlins.

19. Common Structural Steel Materials
Plates – Flat pieces of steel of various thickness used at the intersection of different members.
Bars – Used as supports or braces for other steel parts or connectors
Structural Shapes – Available in several different manufactured shapes

20. Structural Steel Callouts Structural steel materials are specified by shape designation, flange width, and weight in pounds per linear foot
For Example: W 24 x 120

21. Structural Steel Shapes
ST – structural tees cut from S shapes
MT – structural tees cut from M shapes
T – structural tees
Z – zee shapes
HP – steel H piling
W –wide flange shapes
S – American Std. Beam
M – Misc. beam & column shape
C – American Std. Channels
MC – Misc. channel shapes
WT – Structural tees cut from W shapes

22. Shop Drawings
Shop drawings are used to break each individual component of a structural engineering drawing down into fabrication parts
Also referred to as “Fabrication Drawings”

23. Common Connection Methods
Bolting
Nails
Welding

24. Components in a Set of Structural Drawings
Floor Plan
Foundation Plan and Details
Concrete Slab Plan and Details
Roof Framing Plan and Details
Roof Drainage Plan
Building Sections
Exterior Elevations,Panel Plan, and Wall Details
Drawing Revisions

25. Demonstrate Laying out a Set of Architectural/Structural Drawings