Improving Quality in residential projects using KEY CHARACTERISTICS - - PDF document

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Improving Quality in residential projects using

KEY CHARACTERISTICS (KCs)

Lessons learned from the Manufacturing Industry

Andrea Caicedo University of Houston Fall 2011

AGENDA:

• Problem Statement
• Background
• Goals
• Methodology
• Case Study
• Conclusions
• Q & A

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PROBLEM STATEMENT:

• Improve construction quality
• Deviations: 5-10% of total cost (Sun, 1994)
• Planning & Design: 78% (Burati, 1992)
• Nature of residential construction
• Need more efficient systematic

method for delivering quality: Prioritizeefforts & resources Integration

MOTIVATION:

• Residential Construction
• Manufacturing Industry
• Key Characteristics (KC):

Successfully applied since 1980’s

(Thornton, 1996)

Wide range of products Benefits

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BACKGROUND :

• Current Practice
• Previous studies

GOALS:

• Understand KC methodology
• Analyze applicability to residential

construction through a case study

• Facilitate quality improvement
• Provide basis for future work

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METHODOLOGY:

• Define Key Characteristics

methodology

• Apply KC methodology to case study

in residential projects

• Conduct statistical analysis of change
• rders
• Analyze results
• Identify improvement areas

KEY CHARACTERISTICS:

A Key Characteristic (KC) is:

• A feature of a building or building

component, assembly or process whose variation has an unacceptable impact on cost, performance or safety of the final product

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KEY CHARACTERISTICS:

*BASED ON HISTORICAL DATA: REASON FOR FAILURE. (HANA, 1999)*

KEY CHARACTERISTICS: STEPS:

THEORETICAL FRAMEWORK

Identification

Critical System Requirements List CSR

Identify requirements & specs.

System KC Flow down

Documentation

Implementation

Monitoring & Mitigation

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• Analyze change order data from

residential projects of similar characteristics

• Apply KC methodology :
• Prioritize Key quality improvement

areas

• Promote integration between design

and construction

KC -CASE STUDY GOALS:

• Change order: “changes that are

generated by unanticipated sources”

• Quality: “conformance to established

requirements” = Customer Satisfaction Changes are quality problems Improve quality by reducing change

• rders

KC -CASE STUDY:

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DATA COLLECTION PROCESS

KC -CASE STUDY:

• Change order data received on total of 7 projects, after

further review 4 projects were considered for this case study

KC -CASE STUDY:

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KC -CASE STUDY:

LEVEL 2:

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0% 1% 2% 3% 4% 5% 6% 7%

CONTRIBUTION DEGREE

PLANNING & DESIGN CHANGE DECISION MAKING UNKNOWN SITE CONDITIONS CHANGE CODES/REGULATIONS SAFETY CD: CONTRIBUTION DEGREE INDEX MEASURES THE DEGREE OF CONTRIBUTION OF A GIVEN CAUSE IN THE PROJECT COST

KC -CASE STUDY

LEVEL 2:

KC –STEPS:

Identification

CSR

Identify requirements & specs.

CDR: CRITICAL SYSTEM REQUIREMENTS

LEVEL 3:

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KC –STEPS:

Identification

SYSTEM KC

RANKING

RANK 1: FREQUENCY ONLY RANK 2: FREQUENCY & MEAN COST RANK 3: STANDARD DEVIATION & MEAN COST

LEVEL 4:

KC –STEPS:

Identification

SYSTEM KC

RANKING

LEVEL 4:

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KC –STEPS:

Identification

FLOWDOWN

SYSTEM KC ASSEMBLY KC PART KC PROCESS KC ASSEMBLY KC PART KC PART KC

WHAT CONTRIBUTES TO SYSTEM KC VARIATION?

LEVEL 5:

KC –STEPS:

Identification

FLOWDOWN

WHAT CONTRIBUTES TO SYSTEM KC VARIATION?

LEVEL 5:

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CONCLUSIONS KC METHODOLOGY: CONCLUSIONS:

• Systematic method
• Prioritize
• Resources allocated properly
• Time is potentially reduced
• Focus on key areas that will improve overall product
• Supports integration:
• Identifies areas that need to be discussed
• Overwhelming amounts of data can be reduced to key

elements

• Integrates Design and Construction
• Encourages dialog
• Project as a whole (big pictures)
• Results were shared with collaborating firms

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CONCLUSIONS:

• Limitations
• Data collection
• Need for more data
• Benefits of collecting data (unknown)
• Residential Construction:
• Teams are smaller
• Communication is simplified
• Future Studies
• Applied to other type of projects
• Implementation and monitoring
• Applied as support of other methods

THANK YOU

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SUPPORTING SLIDES: SUPPORTING SLIDES:

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SUPPORTING SLIDES:

50000 100000 150000 200000 250000 300000 5 10 15 20 25 30 FRAMING 50000 100000 150000 200000 250000 300000 1 2 3 4 5 6 7 8 9 FINISH CARPENTRY

SUPPORTING SLIDES:

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SUPPORTING SLIDES:

100 200 300 400 500 600 700 800 900

RANK 2 COST INDEX

0.00 0.20 0.40 0.60 0.80 1.00 1.20

RANK 3 RISK INDEX

RANK 3 RISK INDEX

SUPPORTING SLIDES:

EXISTING METHODS

Six Sigma Overlooks systematic methods for identifying best

• pportunities for

improvement Use of KC can improve effectiveness

• f program

Lean Construction Similar philosophy of achieving goals. Higher quality, lower cost, shorter time. Shares philosophy, however, some improving

• pportunities are

better than others TQM Focused on

• rganization

improvement. Broader goals, broader definition of quality Systematic and detailed quality improvement

• pportunities