【内容简介】Simplify the estimating process with the latest data, materials, and practices

Electrical Estimating Methods, Fourth Edition is a comprehensive guide to estimating electrical costs, with data provided by leading construction database RS Means. The book covers the materials and processes encountered by the modern contractor, and provides all the information professionals need to make the most precise estimate. The fourth edition has been updated to reflect the changing materials, techniques, and practices in the field, and provides the most recent Means cost data available. The complexity of electrical systems can make accurate estimation difficult, but this guide contains all the necessary information in one place.

An electrical estimate represents the total cost for materials, labor, overhead and profit, but accuracy is virtually impossible without a basic knowledge of the field, and real-world experience in the type of work required. Inaccurate estimates lead to problems with customer satisfaction, which often create payment issues. A thorough, complete, and accurate estimate is in the best interest of all parties involved in the work. Electrical Estimating Methodsprovides more than just data. Detailed discussions about the work itself help highlight factors that may escape notice, and access to the latest cost data helps tie everything together. Features include:

• Discussion of current equipment, materials, and processes
• Means data for both residential and commercial projects
• Case studies that illustrate best practices
• Online access to the latest Means data for fast access on the job

The book discusses specific situations as well as general practices, and provides comprehensive guidance to the creation of a true, current, estimation of costs. For electrical contractors and estimators, Electrical Estimating Methods contains must-have content that simplifies the estimating process.

【目录】

PART 1 THE ESTIMATING PROCESS 1

CHAPTER 1 Components of an Estimate 3

CHAPTER 2 Types of Estimates 7

Order of Magnitude Estimates 8

Square Foot Estimates 9

Assemblies Estimates 10

Unit Price Estimates 11

CHAPTER 3 Before Starting the Estimate 15

Obtaining Bid Documents 15

To Bid or Not to Bid 15

Document Study 16

Estimating Team Meeting 17

CHAPTER 4 The Quantity Takeoff 19

Beginning the Quantity Takeoff 19

Rules to Follow for Accurate Takeoffs 20

Accounting for Waste 24

Other Factors that Affect Quantities 26

CHAPTER 5 Pricing the Estimate 27

Sources of Cost Data 27

Cost Categories 29

Types of Costs 29

Profit 29

CHAPTER 6 Direct Costs 31

Material 31

Labor 33

Equipment 37

Subcontractors 38

Project Overhead 40

Bonds 42

CHAPTER 7 Indirect Costs 45

Home Office Overhead 45

Profit and Contingencies 48

CHAPTER 8 The Unit Price, Project Overhead Summary, and Estimate Summary Sheets 55

Unit Price Sheet 55

Project Overhead Summary Sheet 56

The Estimate Summary Sheet 59

CHAPTER 9 Prebid Scheduling 69

Scheduling Theory 69

Critical Path Method (CPM) 70

Value of the Prebid Schedule 71

Task Types 72

Task Durations 73

Calculating Durations 74

Milestones and Constraints 76

CHAPTER 10 Bidding Strategies 77

The Business Plan 77

Competitive Bidding 78

Resource Analysis 80

Market Analysis 81

General Bidding Strategies 82

Maximizing the Profit-to-Volume Ratio 84

CHAPTER 11 Project Cost Control and Analysis 87

Cost Control 87

Productivity and Efficiency 90

Overtime Impact 91

PART 2 COMPONENTS OF ELECTRICAL SYSTEMS 93

CHAPTER 12 Raceways 95

Cable Tray 95

Conduit (to 15′ High) 99

Conduit Fittings 102

Conduit in Concrete Slab 104

Conduit in Trench 105

Cutting and Drilling 106

Wire Duct—Plastic 108

Trench Duct 109

Underfloor Duct 110

Surface Metal Raceways 113

Wireways 114

Flexible Metallic Conduit 116

CHAPTER 13 Conductors and Grounding 119

Wire 119

Armored Cable 123

Cable Terminations (to 600 Volt) 123

Shielded Power Cables 125

Cable Terminations (High Voltage) 126

Mineral Insulated Cable 127

Nonmetallic Sheathed Cable 128

Fiber-Optic Cable Systems 129

Special Wires 130

Grounding 131

Undercarpet Wiring 133

Undercarpet Telephone Systems 135

Undercarpet Data Systems 137

CHAPTER 14 Boxes and Wiring Devices 141

Pull Boxes and Cabinets 141

Outlet Boxes 142

Wiring Devices and Low-Voltage Switching 144

Fasteners 145

Hangers 147

CHAPTER 15 Starters, Boards, and Switches 149

Circuit Breakers 149

Control Stations 150

Fuses 151

Load Centers 153

Meter Centers and Sockets 154

Motor Control Center 155

Motor Control Center Components 157

Motor Connections 159

Motors 160

Motor Starters and Controls 161

Contactors 165

Relay 166

Panelboards 167

Panelboard Circuit Breakers 169

Safety Switches 170

Switchboards 172

Substations 174

Control Switches 176

CHAPTER 16 Transformers and Bus Duct 179

Transformers 179

Isolating Panels 180

Bus Duct 182

Bus DuctBusway—100A and Less 184

Uninterruptible Power Supply Systems 186

CHAPTER 17 Power Systems and Capacitors 187

Capacitors 187

Generator Set 188

Automatic and Manual Transfer Switches 190

CHAPTER 18 Lighting 193

Interior Lighting Fixtures 193

Exit and Emergency Lighting 196

Exterior Fixtures 197

Lamps 199

Track Lighting 200

Fixture Whips 201

CHAPTER 19 Electrical Utilities 205

Electric Site Work 205

CHAPTER 20 Special Systems 211

Special Systems 211

Clock Systems 211

Detection Systems 212

Doorbell Systems 214

Electric Heating 215

Lightning Protection 218

Nurses’ Call Systems 220

Closed-Circuit TV Systems 222

Residential Wiring 224

CHAPTER 21 Electrical Demolition and Temporary Facilities 229

Defining the Electrical Demolition Scope 230

Electrical Demolition 231

Temporary Facilities 232

CHAPTER 22 Contract Modifications 235

Contract Modifications 235

What Makes Change Orders Different 238

Effects of Overtime 240

CHAPTER 23 Project Closeout 243

The Closeout Process 243

Objectives of the Closeout Process 245

Contract Closeout 245

Administrative Closeout 246

Lessons Learned 246

CHAPTER 24 Computerized Estimating 249

Basic Spreadsheet Programs 250

Stand-Alone Estimating Software 252

Quantity Takeoff Software 253

APPENDIX

Symbols and Abbreviations 255

Trade Specific Symbols 255

Index 265