1/23/2012 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 1
1/23/2012 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 2
1/23/2012 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 3
1/23/2012 METHODOLOGY: • Define Key Characteristics methodology • Apply KC methodology to case study in residential projects • Conduct statistical analysis of change orders • 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 4
1/23/2012 KEY CHARACTERISTICS: *BASED ON HISTORICAL DATA: REASON FOR FAILURE. (HANA, 1999)* KEY CHARACTERISTICS: STEPS: Critical System Identify Requirements List requirements & specs. CSR Identification System KC Flow down Documentation Implementation Monitoring & Mitigation THEORETICAL FRAMEWORK 5
1/23/2012 KC -CASE STUDY GOALS : • 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: • 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 orders 6
1/23/2012 KC -CASE STUDY: 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 7
1/23/2012 KC -CASE STUDY: LEVEL 2: 8
1/23/2012 KC -CASE STUDY LEVEL 2: 7% CONTRIBUTION DEGREE PLANNING & DESIGN 6% 5% CHANGE DECISION MAKING 4% UNKNOWN SITE CONDITIONS 3% CHANGE CODES/REGULATIONS 2% 1% SAFETY 0% CD: CONTRIBUTION DEGREE INDEX MEASURES THE DEGREE OF CONTRIBUTION OF A GIVEN CAUSE IN THE PROJECT COST KC –STEPS: Identify requirements & CSR Identification specs. LEVEL 3: CDR: CRITICAL SYSTEM REQUIREMENTS 9
1/23/2012 KC –STEPS: SYSTEM KC Identification RANKING LEVEL 4: RANK 1: FREQUENCY ONLY RANK 2: FREQUENCY & MEAN COST RANK 3: STANDARD DEVIATION & MEAN COST KC –STEPS: SYSTEM KC Identification RANKING LEVEL 4: 10
1/23/2012 KC –STEPS: Identification FLOWDOWN ASSEMBLY PROCESS PART KC KC KC SYSTEM KC PART KC ASSEMBLY KC PART KC LEVEL 5: WHAT CONTRIBUTES TO SYSTEM KC VARIATION? KC –STEPS: Identification FLOWDOWN LEVEL 5: WHAT CONTRIBUTES TO SYSTEM KC VARIATION? 11
1/23/2012 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 • 12
1/23/2012 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 13
1/23/2012 SUPPORTING SLIDES: SUPPORTING SLIDES: 14
1/23/2012 SUPPORTING SLIDES: 300000 250000 200000 150000 FRAMING 100000 50000 0 0 5 10 15 20 25 30 300000 250000 200000 150000 FINISH CARPENTRY 100000 50000 0 0 1 2 3 4 5 6 7 8 9 SUPPORTING SLIDES: 15
1/23/2012 SUPPORTING SLIDES: RANK 2 COST INDEX 900 800 700 600 500 400 300 200 100 0 RANK 3 RISK INDEX 1.20 1.00 0.80 0.60 0.40 RANK 3 RISK INDEX 0.20 0.00 SUPPORTING SLIDES: EXISTING METHODS Overlooks systematic methods for Use of KC can Six Sigma identifying best improve effectiveness opportunities for of program improvement Shares philosophy, Similar philosophy of however, some achieving goals. Lean Construction improving Higher quality, lower opportunities are cost, shorter time. better than others Focused on organization Systematic and improvement. detailed quality TQM Broader goals, improvement broader definition of opportunities quality 16
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