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Lecture notes
Department of Architecture, Cornell University

ARCH 2614/5614 Building Technology I: Materials and Methods

Jonathan Ochshorn

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Overview of technical documents and specifications

Construction documents

Purpose of the construction documents

The construction documents include:

  1. LEGAL: contractual information, typically in a "project manual"
  2. PROCEDURAL: administrative stuff, typically in Division 01 of the specifications, as well as in Part 1 of each additional specification section
  3. CONSTRUCTION: architectural/construction information, typically included in the drawings and specifications (formerly divisions 2-16; now 2-49 in Masterformat 2004)

Note: the construction documents are NOT a set of instruction on "how to build the building." In U.S. practice, the contractor retains much responsibility to deal with construction means, methods, techniques, sequences, procedures, site safety, and so on.

Notes on process:

AIA Document A201 General Conditions of the Contract for Construction, contains typical conditions which are expanded upon in Division 1 of the Specifications:

Part 1 of other Specification sections include:

Notes on drawings and specifications:

Drawings: quantities, configurations (geometry)

Specifications: qualities, standards of craftsmanship.

Specifications are written in 3 parts:

  1. General
  2. Products
  3. Execution

Graphic summary of the various construction documents:

overview of building documentation

Outline specifications

Comparison with full specifications

Unlike outline specifications, full specifications have a three-part organization for each Masterformat section, as follows:

  1. General
  2. Products
  3. Execution

These can be extremely detailed, unlike the short summaries typical of outline specifications.

Examples of manufacturers' specifications for their products can be found here, or here, or here. More "generic" spec libraries can be purchased from organizations such the AIA.


CAD Standards: layers, sheet organization, etc.

Based on National CAD Standard v.6: access Library online version here [Cornell students only]

Drawing set organization: use discipline designators (e.g., A for architectural) and sheet types (e.g., plans, elevations, sections, large-scale views, details, schedules/diagrams, and 3D representations); use standard formats for sheets (size, layout) and schedules.

A. Set content and order:

B. Note that different drawing sets are produced during the life of the project:

C. Order of drawings according to the discipline designators (i.e, drawing "subsets")

An example of a "level 2" discipline designator is "ET" for electrical telecommunications, where the "level 1" discipline designator, "E," is just plain electrical.

D. Sheet identification:

In the following descriptive tables, A = alphabetical character and N = numerical character.


A A N N N

Discipline designator


A A N N N

Sheet type designator


A A N N N

Sheet sequence number


Notes:

E. Naming files

"Library" versus "project" files (for electronic data).

Library files are more generic and can be used in various projects.

use masterformat or uniformat system to group such files.

copy and modify, rather than modifying the original library file; rename as appropriate for each project.

Project files are specific to a project, and include such things as building or site models, details, sheets, etc.

For example, a detail file may include plans, elevations, sections, or details; they use the "dot" prior to a suffix, as follows: A-NNN-AN.AAA or A-501-B3.DWG

In this designation, A-501 is the sheet identification, B3 is the detail identification number (referring to the coordinate location on the sheet).

Text files could be such things as general notes, etc.

Database files include the formatting and information needed for schedules and other lists.

F. Sheet organization

Sheet size: determined primarily by plan size; sometimes necessary to subdivide plans, in which case a key plan is needed.

Government projects (federal only) are metric and use ANSI official sheet sizes. See chart below:

ANSIISOArchitectural 
Mark Size
mm
(inches)
Mark Size
mm
(inches)
Mark Size
mm
(inches)
Typ. applications
A 216x279
(8.5x11)
A4 210x297
(8.3x11.7)
A 229x305
(9x12)
project manual, supplementary dwgs, mock-up sheets
B 279x432
(11x17)
A3 297x420
(11.7x16.5)
B 305x457
(12x18)
"A1" originals, some reduced dwgs, supplementals and mock-ups
C 432x559
(17x22)
A2 420x554
(16.5x22.4)
C 457x610
(18x24)
small projects where sheet size is compatible with plan dimensions
D 559x864
(22x34)
A1 594x841
(23.4x33.1)
D 610x914
(24x36)
government projects; other projects consistent with plan size
E 864x1118
(33x44)
A0 841x1189
(33.1x46.8)
E 914x1219
(36x48)
large projects
        F 762x1067
(30x42)
alternate size, consistent with plan dimensions

Sheet layout:

What about BIM?

BIM is an acronym for "building information modeling," a way to represent a building digitally by creating a parametric model. For example, a "window" can be "attached" to (or "hosted" by) a wall so that when the wall moves, the window goes with it. This "window" also contains actual properties of the window embedded as data, so that things like energy analysis, cost estimating, and specifications can be automatically generated. In general, changes made to one element of the BIM model automatically generate appropriate changes throughout the whole model. Importantly, coordination becomes more systematic: various consultants using the same BIM model can avoid costly errors, e.g., showing mechanical ducts running through structural beams. See this analysis of BIM prepared by Autodesk.

BIM has its own objectives and standards. Here's what Autodesk University says about the relationship between BIM and the National CAD Standard:

"The National Building Information Modeling Standard (NBIMS) doesn't attempt to define graphical standards so the United States National CAD Standard (NCS) remains the standard for the foreseeable future. The NCS still applies because much of the output from BIM is still printed drawings and CAD exports. Which standard applies to what? Where should those transitioning from a CAD to BIM environment look within these standards for guidance? A BIM module is being developed to interconnect the National CAD Standard and the National BIM Standard to address these questions and more. This roundtable discussion gives attendees the opportunity to provide input that shapes a BIM module within the National CAD Standard to interconnect the standards. Attendees also gain knowledge on how to get involved in future development of the standards."
Connecting the National CAD and BIM Standards

Cornell students have access to Revit tutorials (scroll down to bottom).