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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Serie: RSMeans
- Sprache: Englisch
A practical, hands-on guide to real-world construction estimating
How to Estimate with RSMeans Data is the only instructional book on construction cost estimating that uses the most popular source of construction cost data, RS Means. This updated fifth edition includes new coverage on the role of Building Information Modeling (BIM) in the estimating process, and over 300 sample problems and exercises that show you how to apply cost data to your building project based on the RS Means 2015 Building Construction Cost Data. The companion website provides access to RS Means CostWorks data, allowing you to use real-world numbers in your practice estimates, and the included Instructor's Manual provides step-by-step solutions to problems in the book. Focused on the practical aspects of estimating, this book emphasizes the application of estimating techniques—which are transferable to any estimating software—through problem solving and the ground-up creation of complete construction project estimates.
Estimating skills are fundamental to the construction industry, and are applied by all parties at all levels throughout the industry. This book is a hands-on guide to the techniques and tools used to create a thorough estimate, with plenty of opportunities for practice.
- Apply cost data to all aspects of the building project
- Practice your skills on over 300 sample problems
- Construct a complete estimate using RSMeans
Besides being an essential construction skill, learning estimating helps you become familiar with reading and understanding construction blueprints and how construction assemblies are built. Mastery of these vital skills is important to your future career, and How to Estimate with RSMeans Data is your ideal guide to a solid foundation.
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Veröffentlichungsjahr: 2020
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How to Estimate with
RSMeans Data
Basic Skills for Building Construction
Fifth Edition
Saleh Mubarak
RSMeans
This book is printed on acid-free paper.
Copyright © 2020 by John Wiley & Sons, Inc. All rights reserved.
Published by John Wiley & Sons, Inc., Hoboken, New Jersey.
Published simultaneously in Canada.
No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at www.wiley.com/go/permissions.
Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with the respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor the author shall be liable for damages arising herefrom.
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Cover Design: Wiley Cover Images: 3D architecture abstract © nadla/iStockphoto; Store Building Exterior © Tony Tremblay/iStockphoto; Steel Construction © SimplyCreativePhotography/iStockphoto; Modern Office Building © Tony Tremblay/iStockphoto; Construction Workers © shotbydave/iStockphoto; Home Under Construction © bbourdages/iStockphoto
Library of Congress Cataloging-in-Publication Data
Names: Mubarak, Saleh A. (Saleh Altayeb) | R.S. Means Company.
Title: How to estimate with RSMeans data : basic skills for building construction / RSMeans, Saleh Mubarak.
Description: Fifth edition. | Hoboken, New Jersey : John Wiley & Sons Inc., [2016] | Includes indexes.
Identifiers: LCCN 2016018464| ISBN 9781118977965 (pbk. : acid-free paper) | ISBN 9781118977972 (epub)
Subjects: LCSH: Building–Estimates.
Classification: LCC TH435 .M79 2016 | DDC 692/.5–dc23 LC record available at https://lccn.loc.gov/2016018464
978-1-118-97796-5
CONTENTS
Cover
Preface
Acknowledgments
Introduction
Chapter 1: Basic Calculations
RSMeans Cost Data Format
Productivity and Activity Duration
Equipment Costs
City Cost Indexes and Location Factors
Notes
Chapter 2: Spreadsheet Types
Manual Spreadsheets
Electronic Spreadsheets
Using RSMeans Online Estimating
Square Foot Estimator
Chapter 2 Exercises—Set A
Chapter 2 Exercises—Set B
Notes
Chapter 3: Cost Estimating: An Introduction
Introduction
Definitions
Types and Purposes of Estimates
Types of Contract Award Methods
Types of Contract Agreements
Chapter 3 Exercises—Set A
Chapter 3 Exercises—Set B
Notes
Chapter 4: General Requirements
Estimating General Requirements
Project Duration
Architectural and Engineering Fees
Workers’ Compensation Insurance
Builder’s Risk Insurance
Sales Tax
Chapter 4 Exercises—Set A
Chapter 4 Exercises—Set B
Notes
Chapter 5: Adjusting RSMeans Data to Job Conditions
Markups on Labor Cost
Interpolation between RSMeans Items
Substituting Known Local Labor Rates
Overtime Productivity Loss and Extra Pay
Effect of Inflation/Cost Escalation
Unit Consistency
Adding Custom Data
Adding, Changing, or Deleting Costs
Chapter 5 Exercises—Set A
Chapter 5 Exercises—Set B
Note
Chapter 6: Concrete:
Division 3
Types of Concrete
Estimating Concrete
Additional Estimating Examples
Chapter 6 Exercises—Set A
Chapter 6 Exercises—Set B
Notes
Chapter 7: Masonry:
Division 4
Types of Masonry
Estimating and Waste Allowances
Productivity Factors
Quantity Takeoff
Chapter 7 Exercises—Set A
Chapter 7 Exercises—Set B
Notes
Chapter 8: Metals:
Division 5
Estimating Structural Steel
Chapter 8 Exercises—Set A
Chapter 8 Exercises—Set B
Notes
Chapter 9: Wood and Plastics, Thermal and Moisture Protection:
Divisions 6 and 7
Wood and Wood Products
Nominal versus Real Dimensions
Thermal and Moisture Control
Estimating Wood-Framed Structures
Using Units of Quantity
Chapter 9 Exercises—Set A
Chapter 9 Exercises—Set B
Notes
Chapter 10: Doors and Windows, Interior Finish, and Equipment:
Divisions 8 to 14
Using RSMeans Costs
Division 8: Openings
Division 9: Finishes
Division 10: Specialties
Division 11: Equipment
Division 12: Furnishings
Division 13: Special Construction
Division 14: Conveying Equipment
Chapter 10 Exercises—Set A
Chapter 10 Exercises—Set B
Note
Chapter 11: Fire Suppression, Plumbing, Mechanical, and Electrical:
Divisions 21 to 28
Fire Suppression
Plumbing
Heating, Ventilating, and Air Conditioning
Electrical
Communications
Electronic Safety and Security
Chapter 11 Exercises—Set A
Note
Chapter 12: Earthwork:
Division 31
Types of Earthwork
Soil Excavation
Cost Basis
Truck Capacity
Excavate by Hand or Machine?
Optimum Number of Trucks per Loader
Equipment Rental Costs for Short or Long Periods
Renting versus Owning Equipment
Chapter 12 Exercises—Set A
Chapter 12 Exercises—Set B
Notes
Chapter 13: Equipment Analysis
Equipment Depreciation
Equipment Expenses
Equipment Rental
Chapter 13 Exercises—Set A
Chapter 13 Exercises—Set B
Notes
Chapter 14: Assemblies Estimating
Preliminary Cost Estimating
Assemblies Estimates
Combining Assemblies and Unit Costs
Chapter 14 Exercises—Set A
Chapter 14 Exercises—Set B
Chapter 15: Approximate Estimates
RSMeans Project Costs
Using Online RSMeans Square Foot Estimator
RSMeans Project Costs
Solution
Chapter 15 Exercises—Set A
Chapter 15 Exercises—Set B
Notes
Appendix A: Contractor's Cash Flow
Appendix B: CSI MasterFormat
Appendix C: Sample Estimating Forms
Appendix D: References
Index
End User License Agreement
List of Tables
Chapter 3
Table 3.1
Table 3.2
Chapter 4
Table 4.1
Table 4.2
Table 4.3
Chapter 9
Table 9.1
Chapter 10
Table 10.1
Chapter 12
Table 12.1
Appendix A
Table A.1
Table A.2
List of Illustrations
Chapter 1
Figure 1.1
Figure 1.2
Figure 1.3
Figure 1.4
Figure 1.5
Figure 1.6
Figure 1.7
Figure 1.8
Figure 1.9
Chapter 2
Figure 2.1
Figure 2.2 This Excel spreadsheet calculates the quantities and then applies units prices ...
Figure 2.3 Same result as in Figure 2.2, produced by RS Means online estimating, Advanced ...
Figure 2.4
Figure 2.5
Chapter 3
Figure 3.1 AACE International Cost Estimate Classification Matrix for Building and General...
Figure 3.2 Factors Influencing Type of Estimate and Accuracy Range
Figure 3.3 Relationship between Preparation Effort and Expected Accuracy
Chapter 4
Figure 4.1 Fast-Track Projects
Chapter 5
Figure 5.1
Figure 5.2
Figure 5.3
Figure 5.4
Figure 5.5
Figure 5.6
Figure 5.7
Figure 5.8
Figure 5.9
Figure 5.10
Figure 5.11
Figure 5.12
Figure 5.13
Figure 5.14A
Figure 5.14B
Figure 5.15
Figure 5.16
Chapter 6
Figure 6.1
Figure 6.2
Figure 6.3
Figure 6.4
Figure 6.5
Figure 6.6
Figure 6.7
Chapter 7
Figure 7.1
Figure 7.2
Chapter 8
Figure 8.1
Chapter 9
Figure 9.1 Calculating Rafter Length
Figure 9.2
Figure 9.3 Floor Framing Plan
Figure 9.4 Floor Framing Cross-Section
Figure 9.6
Figure 9.7
Figure 9.8
Chapter 10
Figure 10.1
Figure 10.2
Chapter 12
Figure 12.1
Figure 12.2
Figure 12.3
Figure 12.4
Chapter 13
Figure 13.1
Figure 13.2
Figure 13.3
Chapter 14
Figure 14.1
Figure 14.2
Figure 14.3
Chapter 15
Figure 15.1
Figure 15.2
Figure 15.3
Figure 15.4
Figure 15.5
Figure 15.6
Figure 15.7
Figure 15.8 Square Foot Project Size Modifier
Figure 15.9
Appendix A
Figure A.2 Contractor's Progress Payment Monthly Cycle
Figure A.1 Typical Contractor's Spending and Reimbursement in a Project
Guide
Cover
Table of Contents
Preface
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Preface
This fifth edition is a continuation of the success of this book. Success can never come as a coincidence or by luck. It comes only through planned, hard, and intelligent work.
Professional estimators quantify the needed resources—materials, labor, and equipment—required by the scope of a project, and then price these items. This is a two-phase process that includes quantity takeoff and cost estimating. To complete the quantity takeoff, the estimator examines plans and specifications to determine total quantities of materials required, as well as labor and equipment. During the cost estimating phase, the estimator examines the direct costs of installed materials and equipment, labor rates, construction equipment and tool costs, and indirect expenses, such as overhead and profit. Inflation and market conditions are additional factors to consider. The estimator needs also to be familiar with the contract, especially the sections relevant to or impacting the cost.
Special problem-solving skills are required to obtain an accurate estimate. No matter what source is used, construction cost data are rarely available in the perfect format for a particular estimate. Data must often be adapted in some way, such as changing the number of units, the location, production rates, or the type of labor. Frequently, there is “math and more” to be done beyond what is required to produce the quantity takeoff, such as converting units of measure, adjusting for overtime, allowing for difficult access to the site, or factoring in other special considerations. Time-cost trade-off is another important consideration as owners and contractors need in some situations to accelerate the project, which has direct and perhaps complicated impact on the total cost.
This book provides information about how the costs in RSMeans Building Construction Cost Data (BCCD) are developed and presented. It also provides numerous sample problems that show how to apply this cost information. Following these guidelines will enable you to use the BCCD “to the max,” creating a detailed estimate, made more accurate by utilizing the full capabilities of the data.
There are many changes in the fifth edition. Chapter 3, “Cost Estimating: An Introduction” has been expanded, adding new sections. I found this chapter particularly important for those who want to get an idea on construction cost estimating without reading an entire book on the subject. More examples and exercises were added. The CSI MasterFormat has been updated according to the 2016 version, which is periodically being updated by the Construction Specifications Institute (CSI) since the major update in 2004 that took the number of divisions from 16 to 50. Chapter 4, “General Requirements,” was expanded and moved to the front of the book.
The book now is published by Wiley, an international leader in publishing scientific and professional books. RSMeans is still involved with the book, particularly in updating the materials related to the online estimating (construction cost estimating database and software).1
The answers and solutions to the exercises were rearranged on a companion website (www.wiley.com/go/constructionestim5e) where users of the book will be given access. The solutions to Exercises—Set B will be available online only to instructors.
Included with this workbook is access to RSMeans Online Estimating, the electronic version of RSMeans Building Construction Cost Data. Students should redeem their access codes at this URL: www.rsmeans.com/academic.aspx. Professionals can access RSMeans Online through a 30-day trial at this URL: www.rsmeans.com/free-trial.aspx. Users can practice their skills in creating a complete construction estimate using the building plans for a residential and a light commercial structure (provided online).
All numbers in the examples and exercises in this book are based on the 2017 RSMeans BCCD (Building Construction Cost Database).
This book focuses on solution techniques for the various types of estimating problems and on using RSMeans Online Estimating to create a spreadsheet estimate. Theoretical explanations of the various estimating techniques are beyond the scope of this publication.
As we improve in each new edition, we are striving for perfection, which humans can never reach. To me, this is good news because it means there is always room for improvement. This is what motivates us to keep improving with no limitation or ceiling. I hope all users of this book—instructors, students, professionals, and others—to communicate with me or the publisher for any idea or correction that can improve this book. The author can be reached at the email address [email protected].
Note
1
In the past four editions, RS Means provided with this book a CD containing construction cost estimating database and a software called CostWorks. Although the CD is still available for purchase separately, this fifth edition of the book uses the online estimating instead.
Acknowledgments
This fifth edition comes on the heels of the fourth edition, when this book was published by Wiley, an international leader in publishing. RSMeans, the leading company in construction cost estimating databases, in still a partner and contributor to the book, including the construction cost estimating database and software. Both organizations have been superb in support and service. My experience with RS Means goes back to 1986 when I used their Building Construction Cost Data (BCCD) book as a graduate student. I have used it again as a professor since 1990.
I would like to thank the engineering team at Gordian for their help with this edition. I would also like to thank the team at Wiley for great support. Wiley took care of my book Construction Project Scheduling and Control and did a great job. They are the world's experts in publishing and marketing scientific books, and I am glad they are publishing this book as well.
I must also recognize the contribution of Tom Bledsaw, currently with Draper, Inc. and formerly with ITT educational Services as the national chair, School of Drafting and Design, and Harold Grimes, the department chair of construction management and general education at Redstone College, as reviewers of this edition.
Finally, I owe a lot of gratitude to the numerous friends and colleagues who passed their comments on the book to me. As humans, we are far from perfection, but I take this as a motivator: there is always room for improvement.
Introduction
RSMeans data from Gordian provides accurate and up-to-date cost information to help owners, developers, architects, engineers, contractors and others carefully and precisely project and control the cost of both new building construction and renovation projects.
This book is based on the RSMeans Building Construction Costs Database, BCCD, which has been printed in books for over 80 years and is now available online. Along with the BCCD online database, RSMeans has provided a cost estimating software. We will refer to it in the book as the RSMeans Online Estimating. It offers a single line item, assemblies, and square foot estimating programs. Users of the book will be given free access to limited use as a supplement to this book.
Instructional Information
First, the user needs to register. Once registration is complete, user can long in to the site: www.rsmeansonline.com.
The user will be directed to the “Welcome to RSMeans Online!” page, where he/she needs to set own preferences (Figure 00.1).
Figure 00.1
Complete the choice of preferences and then click “Save & Continue”. This screen will appear every time the user logs in unless the “Display Cost Data Preferences at start-up” is unchecked.
On the main page, we have the main menu with these options:
Search Data: Display of the database, cost line items or assemblies
Manage Estimates: Manages the estimates you created
Square Foot Estimator: A special program for conceptual estimating with more than 100 commercial and residential models available
Life Cycle Cost: An option for improving the long-term performance of buildings and gauge installed costs versus long-term facility maintenance costs
Cost Alerts and Trends: An option to receive notifications and track cost trends for the materials, labor, and equipment
Reference Items: Supplemental information such as a list of abbreviations, city cost index, crews, labor rates, references (notes that relate to cost line items), estimating tips, dictionary (for cost-related terms), a video tutorial, and student edition materials
My Favorites: A special database for items and assemblies you choose as favorite so it will be easy to reuse later
You can always click on the green button “Guide Me” on the upper right-hand side for valuable help lessons.
More explanation on creating and managing estimates through examples in the following chapters.
A Cautionary Note: Numerical Rounding and Mathematical Judgment
Construction cost estimating is not an exact science. It depends on many uncertain factors (labor productivity, price escalation, and so forth) that make absolute accuracy impossible. It is a prediction of future expenses. Assumptions will have to be made about waste factors, contingency costs, takeoff techniques, and many other unknown or uncertain factors. Given the same set of plans and specifications, several estimators will come up with different project totals, all of which will probably differ from the final project cost. The good estimator is the one who gets his estimates consistently close to the actual cost.
Mathematical Intuition
Scholars differ and argue on the definition of mathematical intuition and what factors play in measuring or increasing it. In the context of construction cost estimating, we can simply state that a cost estimator must possess a minimum level of mathematical intuition to enable him or her to make good common sense judgments on numbers and to judge whether a number is too high or too low. Such intuition is essential to avoid major mistakes that may lead to financial losses and other negative consequences. Cost estimators with good mathematical intuition also can provide, in most cases, a ballpark figure for the cost of a proposed project without sophisticated methods and tools.
Although scholars may argue, again, on how much of this mathematical intuition is inherited and how much is acquired, there is no question that any human being can enhance it by learning a few simple techniques and continuous practice. It is just like any other mental and physical power that humans possess; it increases—or at least is maintained—by practice, and decreases by neglect and lack of practice. This point is becoming increasingly important as we have entered the digital age and accumulated plenty of electronic gadgets. Technological advancements and inventions continue day after day with no end (or even a slowdown) in sight.
Our increasing dependence on such gadgets is leaving a negative effect on many talents such as the mathematical intuition. For example, there is no question that the quality of the average human's handwriting has declined because of the overwhelming use of computer and other electronic devices’ keyboards. People now depend more on their cell phones rather their own memory to store telephone numbers and other information. New technologies have also automated many processes such as structural analysis and design, medical diagnosis, and automotive mechanical and electrical diagnosis. As wonderful as it seems to many people, this should trigger an alarm: many people are losing their professional intuition and analytical capability. They are becoming too dependent on technologies to the point they cannot function or perform simple tasks without their electronic devices. Computers and other electronic gadgets are wonderful tools that can and do help tremendously, but they should never be a replacement for the human intelligence, thinking, and creativity.
To the cost estimator, there are simple exercises that can help build or at least maintain this intuition, such as calculating the value of the groceries or other commodities purchased from a store, including any percent discount and sales tax, and then comparing this approximate total to the cashier's total. One can calculate or estimate the monthly payment on a purchased car and compare it with the amount provided by the salesperson. Practice estimating the height of a high-rise building (in feet or meters, or number of floors), the number of bricks in a pallet or group of pallets of bricks, or the number of openings (doors and windows) in a building. It is always a good idea to do quick and approximate mental math and then compare the answer to the one produced by the computer, calculator, or other devices. When the two answers are significantly different, you might discover that the other answer (the supposedly accurate one) is wrong, either through human input error or a software flaw.
Some Helpful Suggestions
Rounding numbers must be done systematically and with care to avoid the introduction of significant errors. It is recommended when performing calculations that you enter dimensions without rounding, especially those to be multiplied by a large quantity. The amount of error in rounding depends on the number(s) the rounded number is multiplied by.
For example, assume an elevated concrete slab is 211′-11″ long, 120′-0″ wide, and 7.5″ thick. The volume is 588.66 CY. If we rounded the length to 212′, the volume would be 588.89 CY, an error of 0.23 CY. However, if we rounded the thickness to 8″ instead of 7.5″, the volume would be 627.90 CY, a whopping 39.24 CY error.
The explanation is easy: the first error represents a 1″ × 120′ × 7.5″ strip (two small and one large dimensions). The second error represents a 211′-11″ × 120′ × 0.5″ strip (one small and two large dimensions). It is important to be careful with such practices, and avoid rounding in early stages of the estimate.
The estimator should have a sense of the size of the error introduced by rounding to ensure that it will not significantly affect the total estimate. Mathematical intuition and good common sense judgment are a must for a good estimator. As one estimator said, “While the price of one item may be too high or too low, the overall estimate should be pretty accurate.”
Be careful when using manual or electronic tools for measuring dimensions. The results produced by rolling pens, digitizing boards, and other tools vary by device and user. Again, the estimator must use common sense judgment to make sure no unmanageable error is introduced into the estimate.
If using a handheld calculator, use one with ordinary fractions capability (b/c), so you can enter 8″ as 8/12 ft, rather than the decimal fraction 0.67. This eliminates the introduction of a rounding error. Follow the same concept when using Excel.
Avoid false accuracy. As cost estimating is a prediction of future expenses, final answers should be rounded to a reasonable degree. As a rule of thumb, a figure with four significant digits is an acceptable accuracy. It would be ridiculous to estimate the total cost of a construction project as $2,148,387.23. This is false accuracy because it gives the reader a feeling that this number is very accurate, while in fact it is not. If it refers to actual expenses, the previous number may be true and accurate. The following are some examples:
Estimate
Estimate Rounded
$122,778.34
$122,800 or 123,000
$367,289.45
$367,000
$2,446,983
$2,447,000
$53,674,294.55
$53,670,000
$453,681,302.88
$453,700,000
In any mathematical operation, the highest level of accuracy for the answer is the same as the accuracy of the least accurate number of that operation. For example, consider:
where B, C, D, E, and F are all real numbers.
The highest accuracy for A is the same as the least accuracy for B, C, D, E, or F. Note that when exact numbers are used, they have a perfect accuracy (or infinite number of significant digits). For example, if we are calculating the volume, in cubic yards, of a concrete footing that measures 3′-4″ by 3′-4″ by l′-4″, the answer would be:
The answer can be rounded to any number of significant digits we desire, such as 0.55, 0.549, 0.5487, and so on.
Suppose volume is written as:
The answer cannot have more than three significant digits because the least accurate number used in the operation had only three significant digits.
RSMeans uses the following rounding standards:
Prices From
To
Rounded to nearest
Use educated common sense judgment. Human errors and equipment malfunctions are always possible. For example, when entering a number in a calculator or a computer keyboard, you may intend to press the 8 key, but the key got stuck and multiple of 8s were displayed instead, or nothing at all. To minimize such errors, follow these three rules:
Always keep an eye on the computer screen or calculator display to make sure it matches the entered number.
Apply common sense judgment to the answer. For example, if you are calculating the cost of erecting wood joists for one floor in a 2,000 SF house, and the answer was too high (e.g., $459,000) or too low (e.g., $570), you know there is something wrong. This judgment depends on the estimator's experience and construction common sense judgment.
Be well-organized and maintain a calculation audit trail. In case of a review or a suspected error, it should be easy for you or anyone else to follow your work, step by step.
Chapter 2Spreadsheet Types
A spreadsheet is simply a sheet containing rows and columns where the user can enter data and perform mathematical calculations. Estimators use spreadsheets when performing takeoffs, pricing estimates, and creating estimate summaries to add markups to bare costs. Spreadsheets may be manual (paper and pencil) or electronic. They may be commercially purchased or custom-designed for internal use within a company. When used efficiently, they can be powerful tools to assist the estimator in managing large quantities of information.
Manual Spreadsheets
Estimators benefit from organizing their work in a format that is easy to read and review. Due to the variety of construction items, there is no single “best form.” The user may develop his or her own form or use a third-party/commercial one. Examples of manual forms specifically for use with some of the examples in this book can be found in Appendix D.
In most formats (see Figure 2.1), the first column contains the description of the item being considered. Columns follow for quantity (how many); dimensions (with subcolumns for length, width, etc.); units; and notes. Other columns are possible for unit price (with possible subcolumns for labor, materials, equipment); extension (Unit price × Quantity); and/or other types of data.
Each estimate form must contain, at the top of the form, a header with identifying information, such as:
Name and address of the company
Name of estimator and supervisor (Estimated By and Checked By)
Name and location of project
Date and perhaps time
Page number and total number of pages (Page ___ of ___)
Source of the information
Any other identifying information, such as Revised Estimate No., Waste Factor, Material Discount, and Labor Rate
Figure 2.1
A complete Estimate Summary form is shown in Appendix D.
Many companies have developed their own forms with the name and logo of the company at the top of each page. The advantage to this is consistency and ease of tracking. The disadvantage is being limited to a specific form.
Electronic Spreadsheets
There are a variety of electronic spreadsheet programs available for personal computers, such as Microsoft Excel, and Quattro-Pro. Specialized cost estimating programs are also available.1 Consumers can choose from a wide variety of construction cost-estimating software programs based on several criteria: high-end or low-end, Excel-based, type of construction (home builders, commercial, industrial), CAD or BIM compatible, general or specialized subcontractor, and other. All of these programs have a built-in spreadsheet and a database. Some can link to accounting, scheduling, contract management, or other software.
When using an electronic spreadsheet program, it is important to be familiar with the software’s specific mathematical functions, including adding and multiplying, as well as more complex mathematical, statistical, logical, and other functions. Excel has become friendlier, and many of its functions appear when the user starts typing the desired function, such as average, median, sum, square root (sqrt), power, sine (sin), log, and so on. The next example shows mathematical operations in Microsoft Excel.
Example 1
