HVACR116 – Trade Skills

Construction Sequence

Introduction

• Construction industry:o Employs about 15% of working people in the U.S. and Canadao More than 60% are involved in new construction

• Classifications of construction: o Residential o Commercialo Industrialo Civil

Introduction (cont’d.)

• Residential construction:o Single family homeso Small apartment buildingso Condominiums

Figure 1–1(A). Residential construction.

Introduction (cont’d.)

• Commercial construction:o Office and apartment

buildingso Hotelso Storeso Shopping centerso Other large buildings

Figure 1–1(B). Commercial construction.

Introduction (cont’d.)

• Industrial construction:o Refinerieso Paper millso Structures other than

buildings

Figure 1–1(C). Industrial construction. Delta Energy Center, water treatment tanks and buildings in the foreground. Courtesy of Bechtel Corporation. Photographer: Terry Lowenthal. Used by

permission.

Introduction (cont’d.)

• Civil construction:o Highwayso Bridgeso Airportso Dams

Figure 1-1(D). Civil construction. At 726 feet, Hover Dam is the highest dam in the United States. Courtesy of Bechtel Corporation. Photographer: Ray Frayne. Used by permission.

The Design Process

• Owner:o Has definite ideas, but may not be an experto Contracts the architect

• Architect:o Combines construction knowledge with artistic abilityo Designs buildings for appearance

The Design Process (cont’d.)

• Architect (cont’d.):o Helps determine:

Space needed Rooms needed Building type Cost

o Makes sketches describing the building before preparing the final drawings.

The Design Process (cont’d.)

Figure 1–2. Balloon sketch of Duplex. Figure 1–3. Straight line sketch of Duplex.

The Design Process (cont’d.)

• Before details are finalized, other professionals become involvedo Building codes specify

requirements International Code Council

publishes several model codes

Figure 1-4. 2006 International Residential Code® for One- and Two-Family Dwellings

The Design Process (cont’d.)

• Local building code:o Often based on a model code.o Administered by local government building department

Reviews plans before construction Inspects throughout construction

• Zoning laws:o Divides community into zones where only certain types of

buildings are permitted

The Design Process (cont’d.)

• Building departments usually require specific procedures to be followedo Building permit

Notifies building department of planned constructiono Certificate of occupancy

Issued when complete construction is approved

Starting Construction

• Financing:o Begins after deciding on final design o Most common form for a home is through a mortgage

• After financing is obtained, a contractor is hiredo Responsible for overall project completiono Hires subcontractors to complete individual parts of the

project

HVACR116 – Trade Skills

Views of Drawings

Starting Construction (cont’d.)

Figure 1–6. Design and construction team.

Isometric Drawings

• Vertical lines are drawn vertically• Horizontal lines are drawn at an angle of 30° from

horizontal

Figure 2–1. Isometric of building.

Isometric Drawings (cont’d.)

• All lines on isometric axes are drawn in proportion to actual lengtho Tend to look out of proportion because we see objects appear

smaller as they get farther away

Figure 2–2. Single-line plumbing isometric.

Figure 2–3. Sketching an isometric brick.

Figure 2–4. Variations on the isometric brick.

Oblique Drawings

• Used when an irregular shape is to be shown• The most irregular surface is drawn in proportion

o As though it were flat against the drawing surface• Parallel lines are added to show depth

Oblique Drawings (cont’d.)

Figure 2–5. Oblique drawing.

Orthographic Projection

• Imagine the object drawn inside a glass boxo Corners and lines representing object edges are projected onto

box sideso If box is unfolded, images projected onto its sides will be on a

single plane, as on a sheet of papero Each view of an object shows only one side

Orthographic Projection (cont’d.)

Figure 2–6. Duplex inside a glass box; method of orthographic projection of roof, front side, and end.

Figure 2–7. Orthographic projection unfolded on a flat sheet of paper.

Orthographic Projection (cont’d.)

• All surfaces parallel to plane of projection are shown in proportion to actual size and shapeo Surfaces not parallel are not shown in proportion

Orthographic Projection (cont’d.)

Figure 2–8. Views of two shed roofs.

Orthographic Projection (cont’d.)

• Construction drawings views:o Plan view shows layout of object viewed from above

Buildings floor layout and foundationo Elevation drawings show height

What would be seen standing in front of a house

Orthographic Projection (cont’d.)

Figure 2–9. Plan view. Figure 2–10. Building elevation.

Orthographic Projection (cont’d.)

• Construction drawings views (cont’d.):o Section view shows what would be exposed if a cut were made

through the object Floor plan

Orthographic Projection (cont’d.)

Figure 2–12. A floor plan is actually a section view of the building. (a) An imaginary cut is made at a level that passes through all windows and doors. (b) The floor plan shows what is left when the top is removed.