Title: Basic Principles of Estimating
1Basic Principles of Estimating
2Estimating
- A prediction of probable cost.
- Is figuring out how to put the pieces together in
the most economical manner. - Estimating is both art and science.
3Estimating (cont.)
- Identify and quantify the pieces-takeoff.
- Identify construction methods.
- Engineering - Will it be stable during
construction? - Productivity
4Bidding is NOT the same as Estimating
- Identify RISK
- How do you get paid?
5Successful Estimating
- Contractors are not in business to win bids.
- Contractors are in business to make money.
- Estimating is the base of a companys success.
6Estimating for Profit
- Good estimating minimizes contractors risk and
facilitates project management and defines the
scope of work. - The estimate is the plan that furnishes the field
people with all the details in a controlled and
prearranged format.
7Estimating Requires
- Skills
- Effort
- Above all, an organized system that will prevent
errors and omissions.
8- Estimating is very expensive therefore, we must
use our time wisely and effectively if we are to
be successful.
9Cost of Estimating
Chart 1
55
50
A
45
40
hours
B
35
30
25
C
20
15
10
100
200
300
400
500
Size of Project in Thousands of Dollars
- A Simple project
- B Medium complexity
- C Difficult project
10Cost of Estimating (cont.)
Chart 2
170
160
A
150
140
130
B
120
hours
110
C
100
90
80
70
60
50
40
30
1.5
2.0
2.5
3.0
3.5
Size of Project in Millions of Dollars
- A Complex
- B Medium complexity
- C Simple
11Profit Should Correlate to Risk
- Job Comparison
- Compare two jobs of identical direct cost, yet
very diverse in overhead and risk factor
Job A Job B Material 200,000 100
,000 Labor 20,000 230,000 Subcontractors
100,000 10,000 General Expenses
30,000 10,000 Subtotal 350,000
350,000 Overhead _at_10 35,000
35,000 Profit _at_10 38,500
38,500 Selling Price 423,500 423,500
12Profit Should Correlate to Risk (cont.)
labor
7
7
7
6
6
5
5
5
5
5
5
4
week
1
2
3
4
5
6
7
8
9
10
11
12
12 weeks ? 65 labors
15
15
labor
10
10
3
3
3
3
2
2
2
2
week
1
2
3
4
5
6
7
8
9
10
11
12
12 weeks ? 65 labors
13Profit Should Correlate to Risk (cont.)
- Materials Low to medium risk
- Labor High risk
- Subcontractors Low risk
- General Expenses Low risk
14Accuracy is Critical for Success
- A typical project can be broken down as follows
- Material 40-45
- Labor 35-40
- Equipment Expenses 8-10
- Overhead 10
- Profit 2
15Common Estimating Mistakes
- Misread or misinterpreted specifications,
drawing, or any other contract document - Takeoff omissions or overlaps
- Missing quotes
- Estimating by unit prices
- Using the percentage method to establish the cost
of certain systems - Prorating indiscriminately
- Crumbling under pressure to procure work
16Common Estimating Mistakes (cont.)
- Cutting prices to meet or beat someone elses
quote - Underestimating the complexity of a project
- Expecting an excessive amount of favorable
changes - Overemphasizing volume purchasing
- Undertaking a project with incomplete bid
documents - Scaling drawings
17How to Improve your Estimating Procedure
- Company labor tables and current material prices
should be stored in your database. - Manual estimating is not cost effective and it is
subject to more errors and omissions. - Computerized estimating should automate and
expedite the manual estimating process. - Establish the company labor unit sand labor
factoring tables. - Maintain current material pricing.
- Establish an estimate review procedure.