Construction Documents Chapter 1 Construction Documents Construction Professionals • Working Drawings and Specifications • Prints • Drafting Methods

Construction professionals, such as architects and contractors, utilize working drawings and specifications to coordinate their efforts in building a structure. Owners, architects, engineers, building officials, contractors, subcontractors, suppliers, and tradesworkers utilize working drawings and prints to coordinate their efforts in building a structure. See Figure 1-1. Accurate working drawings, prints, and specifications ensure that the final project is completed in direct accordance with the intentions of the owner and architect and in compliance with engineering and legal standards. Various parties involved in the project communicate throughout the process to ensure that they agree on the information contained in the prints and specifications.

Plot plans show the shape and size of the building lot and location and shape of the house. Floor plans show the shapes, sizes, and relationships of rooms. A plot plan is a scaled drawing that shows the shape and size of the building lot; location, shape, and overall size of a house on the lot; and the finish floor elevation. Plot plans are drawn to smaller scales than floor plans. The use of a smaller drawing scale allows for drawings of larger areas such as building lots to be shown on a single print page. Solid contour lines on a plot plan show the finish grade of the building lot. Dashed contour lines, when included on a plot plan, show the existing grade. Other information shown on a plot plan includes a symbol designating true north and the point of beginning (POB) from which building corners and heights, location of streets, easements, and utilities are established. See Figure 1‑2.

Floor plans show the shapes, sizes, and relationships of rooms. A floor plan is a scaled view of the various floors in a house looking directly down from a horizontal cutting plane taken 5′‑0″ above each finished floor. Floor plans show the layout of rooms and give information about windows, doors, cabinets, fixtures, and other features. The shapes, sizes, and relationships of rooms are also shown on floor plans. Dimensions show sizes of rooms, hallways, wall thicknesses, opening locations, and other measurements. Symbols and abbreviations provide additional information about the various building components. See Figure 1‑3. A separate floor plan is required for each story of the house. Floor plans are generally the first drawings to be drawn from a set of plans.

Elevations show the sizes and shapes of exterior walls, interior walls, and partitions. An elevation is a scaled view looking directly at an object such as a wall. Elevations show the true shape of the exterior and interior walls without any allowances for perspective in the drawings. Dimensions include floor‑to‑floor heights and heights of windows above finished floors. The two types of elevations are exterior and interior elevations. See Figure 1‑4.

Sections show features revealed by a cutting plane. A section is a scaled view created by passing a cutting plane through a portion of a building. See Figure 1‑5. Common sections are taken through exterior walls to show information about foundation footings and walls, wall and floor framing, height of windows above floors, and eaves and roof construction.

Details show special features of plans as elevation or section views. A detail is a scaled plan, elevation, or section drawn to a larger scale to show special features. Whenever a part of a building cannot be shown clearly at the small scale of the plan, elevation, or section, it is redrawn at a larger scale so that necessary information can be shown more clearly. For example, a fireplace, framing for a stairwell, special interior or exterior trim, an entrance doorway, or a section of a foundation may be drawn as a detail. Section details show the cross‑sectional shape of features such as foundation footings and windows. The scale for the detail is determined by the complexity of the detail. See Figure 1‑6.

Title blocks include the sheet number, architect or design firm name, owner, and other pertinent information. A title block is an area on a working drawing or print that is used to provide written information about the drawing or print. See Figure 1-7. The title block is located along the right side or bottom of the sheet. Title blocks give the number of the sheet and total number of sheets in the set of plans. For example, 1 OF 7 denotes the first sheet of a set of plans containing seven sheets. In a larger set of plans, initials may precede the sheet number to indicate a particular trade area. For example, E1 OF 3 denotes the first electrical sheet of three electrical sheets. Other letters commonly used to denote specific trade area prints are P for plumbing and M for mechanical, which includes heating, ventilating, and air conditioning (HVAC).

Specifications include information such as the materials used in the construction and the responsibilities of those involved. Written information related to the residential project is included in the specifications. See Figure 1-8. This will include information such as the specific lumber grades to be used for various structural components, the loading requirements for concrete slabs and foundations, and any other information required for construction professionals or building code review officials. General notes may also be included directly on a print sheet that may take the form of specifications for a small residential project.

Original drawings are produced using either conventional drafting or CAD. Working drawings are printed using a wide-format printer. With the use of computer-aided design (CAD), building information modeling (BIM), and the on-line transmission of architectural drawings, computer-controlled printers, sometimes referred to as plotters, are commonly used to create working drawings. See Figure 1‑9. LED (light-emitting diode), inkjet, laser, and electrostatic wide-format printers have replaced blueprints and diazo print processes because the prints are quickly and easily produced and their white backgrounds and dark lines make them more legible. LED inkjet, laser, and electrostatic prints are also easily enlarged or reduced. Some wide-format printers have integrated scanners to enable the scanning and printing of existing paper prints.

LED printers use light-emitting diodes to project light onto a photoreceptive drum enabling fast production of detailed working drawings. LED, electrostatic, and laser prints are produced using a process similar to the process that office copiers and printers use. See Figure 1-10. LED printers take electronic print information received from a data source (typically an external electronic file or scan) and route the information through an integrated image processor. The processed information it then sent to a stationary LED array that writes an entire page width of the image information onto an electrically charged photoreceptive drum. Some LED printers use a positively charged drum with positively charged toner, while other LED printers use a negatively charged drum with a negatively charged toner. The LED array spans the width of the page, projecting the image onto the drum as it rotates.

Conventional drafting tools include T squares, triangles, scales, and pencils. Drafting instruments, such as dividers, may also be used to create drawings. Basic tools such as T‑squares, triangles, scales, and pencils are used to produce working drawings by the conventional method. Other drafting instruments such as dividers and compasses are also used to produce working drawings. See Figure 1‑11.

The 30°-60° and 45° triangles are used to draw lines 15° apart. A triangle is a drafting tool used to draw vertical and inclined lines. The base of a triangle is held firmly against the blade of the T‑square for accuracy. Two standard triangles—30°-60° and 45°—are available in a variety of sizes. A 30° -60° triangle is used to produce vertical lines and inclined lines of 30° or 60° sloping to the left or right. A 45° triangle is used to produce vertical lines and inclined lines of 45° sloping to the left or right. The triangles may be used together to produce inclined lines every 15°. Triangles are typically made of clear plastic. See Figure 1‑12.

A compass is used to draw arcs and circles A compass is used to draw arcs and circles. Dividers are used to transfer measurements. Although a wide variety of precision drafting instruments is available, the compass and dividers are the most commonly used instruments. Compasses and dividers are available in varying sizes. See Figure 1‑13.

Three types of scales are used to produce scaled drawings Three types of scales are used to produce scaled drawings. The architect’s scale is typically used for building trades plans. A scale is a drafting tool used to measure lines and reduce or enlarge them proportionally. Three types of scales are the architect’s scale, civil engineer’s scale, and mechanical engineer’s scale. See Figure 1‑14.

Pencil leads range from extremely soft to exceptionally hard. Grades of lead range from 6B (extremely soft) to 9H (exceptionally hard). Hard leads are used to draw fine, precise lines. Medium leads are used to draw object lines. Soft leads are used primarily for sketching. The architect’s range is HB, F, H, and 2H. F and H are most commonly used for producing drawings. See Figure 1‑15.

CAD-generated plans have consistent line weights, symbols, and lettering. Computer‑aided design (CAD) is also known as computer‑aided drafting or computer‑aided drafting and design (CADD). Advantages of CAD include speed, accuracy, consistency, changeability, duplication, and storage. A major additional benefit of a CAD system is its information-management capabilities. As drawings are made or changed, information about the materials used in the drawings is stored and updated, allowing the operator to extract it for estimating or pricing purposes. Advantages of CAD include legibility and consistency of line weights, notes, and symbols. See Figure 1‑16.

A CAD system includes a keyboard, central processing unit (CPU), monitor, and input devices. Input systems are composed of a software program such as AutoCAD® and hardware such as a keyboard, computer, and monitor. See Figure 1‑17. Other input devices such as a mouse, trackball, or other pointing device are commonly used.

Wide-format LED printers are used to print working drawings Wide-format LED printers are used to print working drawings. The printers may have an integrated scanner, stacker, or folder. Output systems can display drawings on a monitor or print drawings on a printer. See Figure 1‑18. Many types of monitors are available to display CAD drawings. A larger monitor is commonly recommended for displaying architectural drawings to enable viewing of smaller details.

Building information modeling (BIM) is used to recognize and resolve any inconsistencies or conflicts between various sets of drawings prior to the beginning of construction. Building information modeling (BIM) is an integrated, electronically managed system that aligns all working drawings, structural drawings, and shop drawings into a consistent system. Electronically generated documents from a variety of sources are translated into a common set of construction drawings. One of the advantages of BIM is that any inconsistencies or conflicts between various sets of drawings can be recognized and resolved prior to discovery of these conflicts at the construction site. See Figure 1-19.