1. © Awad S. Hanna, PhD, P.E.1 Estimating and Scheduling CEE 492 Lecture 8 Sources of Estimation Data

2. © Prof Awad S. Hanna2 Sources of Estimation Data   Company Database   Commercial Cost Books   Published Data   Prototype Modeling   Professional Associations   Previous Bids Ⓒ

3. © Prof Awad S. Hanna3 Ⓒ 1. Company’s Own Cost Data from Previous Projects  Advantages  It reflects quality and productivity of its own equipment and crews.  It reflects company’s management system and construction methods.  Limitations  Accurate field information should be collected and updated.

4. © Prof Awad S. Hanna4 Ⓒ 1. Company’s Own Cost Data from Previous Projects Div.Work Desc.UnitLowAvg.High 2Site worksf0.300.350.39 2Excavation cy3.564.574.93 3Formworksfca2.562.713.11 3Reinforcement lb0.350.380.42 4Masonry sf5.826.217.34 Company's Historical Data

5. Prof. Awad Hanna5  Benefits  Published and updated periodically  Contain specifications, labor rates, labor productivity, prices, photos, calculations, etc.  Most Common References:  Means Building Construction Cost Data, R.S. Means Company  Dodge Manual, McGraw-Hill Cost Information Systems  Walker Building Estimator’s Reference Book, Frank R. Walker Company 2. Commercial Cost Books

6. Prof. Awad Hanna6 Sample of R.S. Means Data

7. Prof. Awad Hanna7 Limitations of Commercial Cost Books  Represent composite data  Average of many projects  Fail to recognize technological changes  Reporting time lag

8. Prof. Awad Hanna8 3. Published Data  Benefits  These guides are valuable to estimators who do not have access to actual job records.  Vendor’s Data  Information published by the manufacturer or distributor which usually gives the unique features and specifications relating to the product.  Example: Sweet’s Catalog

9. Prof. Awad Hanna9 3. Published Data  Periodicals  Gives various construction cost indices for all cities all over North America.  Example: Engineering News Record (ENR)  http://enr.construction.com/features/conEc o/costindexes/default.asp

10. Prof. Awad Hanna10

11. © Prof Awad S. Hanna11 Ⓒ

12. © Prof Awad S. Hanna12 4. Prototype Modeling   Build a model for unique work where no published literature is available.   Examples: spalled concrete on an airfield parking ramp or mock up for building facade Ⓒ

13. © Prof Awad S. Hanna13 5. Professional Associations Ⓒ   Association for the Advancement of Cost Engineering (AACE)   National Estimating Society   Seminars, training organizations, publications

14. © Prof Awad S. Hanna14 6. Previous Bid Tabulations   Available from previous bid openings (public works)   Generally, limited to the lowest three bidders Ⓒ

15. © Prof Awad S. Hanna15 6. Previous Bid Tabulations Ⓒ

16. © Prof Awad S. Hanna16 Workshop 1: Earthwork Estimate Ⓒ Attached is a figure from R.S. Means estimating manual. The top part of the figure shows line items for a typical page from the unit price cost data book. The bottom part shows the crew and equipment used to perform the work. If the daily production for line 300 is lowered to 925 C.Y., find the man-hours per unit and bare costs for labor and equipment.

17. © Prof Awad S. Hanna17 Workshop 1 Solution Ⓒ   Step 1: Calculate new crew productivity   Crew is B-12D   From Crew Table, existing crew productivity = 16 MH/day   Existing productivity is 16MH/day x 1 day/1620 CY = 0.0098 = 0.010 MH/CY   Therefore, new crew productivity is:   16 MH/day x 1 day/925 CY = 0.017 MH/CY

18. © Prof Awad S. Hanna18 Workshop 1 Solution   Step 2: Calculate bare labor costs   Labor costs (from Crew Table):   $186.4 + $153.6 = $340/day   Existing labor costs per unit:   $340/day x 1 day/1620 CY = $0.21/CY   Therefore, new labor costs per unit:   $340/day x 1 day/925 CY = $0.37/CY Ⓒ

19. © Prof Awad S. Hanna19 Workshop 1 Solution   Step 3: Calculate bare equipment costs   Equipment costs (from Crew Table):   $2017/day   Existing equipment costs per unit:   $2017/day x 1 day/1620 CY = $1.25/CY   Therefore, new equipment costs per unit:   $2017/day x 1 day/925 CY = $2.18/CY Ⓒ

20. © Prof Awad S. Hanna20 Conclusion Ⓒ Questions about estimating sources ?