Estimating Final

Problems that can emanate from the practice of subcontractors

Unreliability of some subs
Errors in sub-trade bids
Overlap or underlap in the scope of work
Conditional bids from subs
Bid closing congestion
Compliance with the government positive action requirements regarding minorities

Two main concerns of the contractors when considering unfamiliar subtrade

Is the sub capable of meeting the quality and schedule requirements of its work?
Does the sub have the financial capability required?

An effective evaluation of subtrade companies would involve an investigation of a number of factors including:

The general reputation of the company
The financial status of the company

The general reputation of the company includes:

The quality of previous work performed by the company
The quality of the company's management
The company's disposition in terms of its general cooperativeness and the ease of dealing with company site and office personnel

Information for the investigation can be obtained from several sources:

The sub company itself may supply some details
From industry contacts that worked with the sub under consideration
From bonding companies

The sub company itself may supply some details such as:

Number of years in business
Number of employees
List of equipment owned
References!
Memberships with trade associations

What is Mortar

Mortar is made by mixing portland cement with lime or masonry cement, and sand

Measurement of brick masonry depends on:

Brick unit size
Size of joints between bricks
Wall thickness
Brick bond pattern

Bricks are available in various sizes but the "standard brick" dimensions are:

8 � 4 � 2 2/3 in

Standard dimensions are _______; ______ dimensions will be smaller depending on the thickness of mortar

nominal
Actual

Typical Mortar waste:

20%-25%

Masonry work includes construction with:

Clay bricks
Concrete bricks
Concrete blocks (CMU)
Clay tiles
Stone

ASTM Types of Mortar:

M
S
N
O

Labor-hours required to lay bricks vary with:

Quality of work
Type of bricks
Kind of mortar used
Shape of the walls
Kind of bond pattern
Weather conditions

Standard nominal size of CMU block is:

8in. x 8in. x 16in.

Subs often perform __ or more work on building projects

80%

Project Control Cycle:

Action
Plan
Monitor
Compare

4 M's in Project Control

Money
Material
Manpower
Machinery

How to tell when Project Control is needed?

Unexpected technical problems & lack of expertise (cost, schedule and performance)
Resources not enough
Quality issues raised by the clients
Change in market prices
Task sequencing not done right
Required labor/material unavailable
Longer lead times than

What are the three basic parameters used in EVA?

Budgeted Cost of Work Scheduled (BCWS) or Planned Value (PV)
Budgeted Cost of Work Performed (BCWP) or Earned Value (EV)
Actual Cost of Work Performed (ACWP) or Actual Cost (AC)

What are the two main purposes of using EVA for project control?

It is a project performance measurement methodology
Given a baseline, project managers and project controllers can determine how well the project is meeting scope, time and cost goals

What is the difference between PV (BCWS) and EV (BCWP)?

PV is the sum of the budgets of all the activities scheduled to be completed by a certain date
EV is the sum of the budgets of all the activities completed by a certain date

What are the three scenarios for calculating EAC?

Create a new estimate
AC to date + new estimate
Bring the project back on track with the remaining scope of work
AC to date + remaining budget (BAC-EV)
Continue on with the project
BAC/CPI

What are the shortcomings of EVA?

Quantifying or measuring work in progress can be difficult
Time required for data measurement, input, and manipulation can be significant
These indicators are primitive as the schedule variance cannot alone indicate if the project is behind, on or ahead o