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