Construction Scheduling

• Pages: 311-342

Const ruct ion S ched uling 311

. INTRODUCTION

This chapter introduces the area of construction scheduling. Time is a resource,

and good scheduling practices can help ensure that parties to a construction

project can meet their goals relating to budget, quality, and timely perfor-

mance. This chapter complements, and should be read in conjunction with,

the material in Chapter 11 on Contract Time.1

1. For a detailed treatment of construction scheduling principles, see J. O’BRIEN & F. PLOTNICK,

CPM IN CONSTRUCTION MANAGEMENT (6th ed. 2006); T. GLAVINICH, CONSTRUCTION PLANNING AND SCHEDUL-

ING (2nd ed. 2004) [hereinafter CONSTRUCTION PLANNING AND SCHEDULING]. For a detailed treatment of

the legal aspects of construction scheduling, see J. WICKWIRE, T. DRISCOLL, S. HURLBUT & S. HILLMAN,

CONSTRUCTION SCHEDULING: PREPARATION, LIABILITY, AND CLAIMS (2nd ed. 2003); B. BRAMBLE & M. CAL-

LAHAN, CONSTRUCTION DELAY CLAIMS (3rd ed. 1999). In addition, there are two major organizations

dedicated to promoting professionalism and ethics in scheduling: the Project Management Insti-

tute’s (PMI) College of Scheduling and the Association for the Advancement of Cost Engineering

(AACE) International.

12

Construction Scheduling

MARK J. GRO FF AND JON M. W ICKWI RE

C H A P T E R

311

312 CO N S T RU C T I O N L A W

We begin with a discussion of the types of schedules generally encountered

on construction projects and the requirements usually set forth in standard

contract scheduling specications. This is followed by a discussion of the base-

line schedule and the schedule updating process. Finally, we discuss the major

methodologies used to identify controlling project delays, who bears responsi-

bility for such delays, and issues relating to expert scheduling testimony.

. TYPES OF SCHEDULES

A. Bar C harts

Bar charts are the traditional method of planning and scheduling construction

projects. They are sometimes referred to as Gantt charts, named after Henry L.

Gantt, who rst developed such charts in 1910.2

2. Contel Advanced Systems, Inc., ASBCA No. 49075, 2004-2 B.C.A. (CCH) ¶ 32,664 (2004).

Activities

NTP*

Foundations

Ext. Walls North-East

Ext. Walls South

Roof

Curtain Wall West

Interior Finishes

Submit/Approve Fixtures

Fab./Del Fixtures

MEP** Rough-In

MEP Finishes

Punch List

Contract Completion

*NTP stands for "Notice to Proceed"

**MEP stands for Mechanical/Electric/Plumbing

1716151413121110987654321 18

Months

FIGURE 1

Commercial Building Schedule

Const ruct ion S ched uling 313

A bar chart generally comprises a horizontal scale that provides the time

reference for the project, broken down into increments such as days, weeks,

months, and a vertical list of the project components or work items. Bars are

drawn to graphically represent the time necessary to accomplish each work

item (see Figure 1).3 Although the content of most bar charts is simple, it is

possible to overlay cost and manpower curves over the time grid and the bars

that are plotted for each work time (see Figures 2 and 3).

1. Advantages and Disadvantages of Bar Charts

Bar charts are easy to understand and are especially useful in providing less

sophisticated project participants with a general understanding of the project

plan. Bar charts are also often used in the eld to provide short-term planning

and coordination. These often take the form of what are known as “two-week

3. Figures 1–5 are based on gures prepared by the construction consulting rm TDF, LLC of

Herndon, Virginia.

Activities

NTP

Foundations

Ext. Walls North-East

Ext. Walls South

Roof

Curtain Wall West

Interior Finishes

Submit/Approve Fixtures

Fab./Del Fixtures

MEP Rough-In

MEP Finishes

Punch List

Contract Completion

10

9

8

7

6

5

4

3

2

1

1716151413121110987654321 18

Months

Cumulative Costs (Millions)

FIGURE 2

Commercial Building Schedule—Cost Loaded