Module Set Process. Presentation to the Quality Modular Building Task Force. October 19, 2000

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1 Results from Studies of the Module Set Process Presentation to the Quality Modular Building Task Force October 19, 2000 Dr. Michael A. Mullens, PE - UCF

2 Agenda Background & Approach Findings Conclusions

3 Motivation At 1999 Quality Modular Buildings Task Force meeting, you asked us to study the Set & Finish process.

4 Set & Finish: Definitions Set placement of modular home sections on a permanent foundation Set-Day working day when factory built modules are installed onto a permanent foundation and other critical components are assembled to comprise a weather-tight structure Finish all remaining activities required to complete the home

5 Primary Set & Finish Activities Set-Day Modules placed on foundation Structure made weathertight Finish Exterior finishing Interior electrical Plumbing HVAC Interior finishing Exterior final Appliances 4-8 hours 1-8 weeks Closing Source: MHTI

6 Primary Set & Finish Activities Set-Day Modules and other major components installed Roof components erected Ship loose shingles and flashings installed Temporary waterproofing materials at vulnerable locations on sidewalls Entry ways secured. Source: MHTI

7 Scope Focus on set-day activities Consider finish activities performed by set crew during or immediately after module set Complete siding

8 Objectives Describe how Set & Finish is being done d f bl f Identify possible opportunities for improvement

9 Approach O N D J F M A M J J A 1999 Task Force * Training Class * Firm 1 Studies 1 1 Firm 2 Studies 2 Firm 3 Studies 1 1 Analysis & Reporting

10 Set Studies 1-3 days per study 3 person research team Monitored all set activities For each activity, documented: Start & stop times Manpower used Problems encountered Best practices Video recording of key activities

11 Jose

12 Gauhar

13 Mike

14 Set Studies 1-3 days per study 3 person research team Monitored all set activities For each activity, documented: Start & stop times Manpower used Problems encountered Problems encountered Best practices Communications/feedback Video recording of key activities

15 Elemental Data Time Duration Labor Labor Activity Start End Hr:Min Qty. Hr:Min Notes Time Duration Labor Labor Activityit 3/1/00 Start End Hr:Min Qty. Hr:Min Notes 3/1/00 Set Module C: Stack carrier for Module D and position carrier for Module C 2:07 PM 2:15 PM 0:08 3 0:24 Strip plastic wrap 2:16 PM 2:18 PM 0:02 1 0:02 Drill holes in rim joist for crane cable & release tie-downs 215PM 2:15 225PM 2: : :10 Pull & secure crane cable under Module C 2:18 PM 2:33 PM 0:15 2 0:30 Set module on foundation, position & check 2:33 PM 2:45 PM 0:12 3 0:36 Remove plastic wrap 2:45 PM 2:50 PM 0:05 2 0:10 Set Module C: Strip plastic wrap 2:16 PM 2:18 PM 0:02 1 0:02 This module had been partially stripped by the builder in the staging area at the bottom of the hill. Left on due to rain.

16 Home Design Profile Modules Style 2 4 Cape 4 Ranch 1 Colonial 1

17 Cape: Elevation View

18 Cape: Elevation View

19 Cape: Perspective View

20 Ranch: Perspective View

21 Colonial: Elevation View

22 Set Crew Profile: Affiliation & Size # Cre ews # Cre ews Mfr. Bldr. Indep. Crew Affiliation Crew Size

23 Set Crew Profile: Scope of Work & Experience 6 5 # Crews completed on set day Not completed on set day Set Roofing Siding Scope of Work # Crew ws Low High Crew Experience

24 Manufacturer s Potential Role in Set & Finish Process Delivery only (Firm 2,3) Factory set crews (Firm 1) Set Selected finish activities (siding, drywall) Builder Manufacturers that provide set services are flexible: Allow builders to purchase only what they need Supplement internal set crews with independent crews when needed

25 Set Process: Cape Stage A Strip A Prep A for lift Set A Install gable panels on A Lift roof on A Prep to lift roof on A Stage B Strip B Prep B for lift Set B Install gable panels on B Lift roof on B Prep to lift roof on B Install mid gable panels Flip ridge panels Install dormers Adjust & complete roof Install collar ties Lift & stage shingles

26 Site Prior to Set

27 Staging the Module

28 Stripping the Module

29 Prep for Lift

31 Lifting Module

32 Aligning Columns During Set

33 Lifting the Roof

34 Installing Gable End Panels

35 Installed Gable End Panel

36 Setting 2 nd Module

37 Installing Attic Floor Decking

38 Installing Mid Gable End Panel

39 Flipping Ridge Panel

40 Installing Dormers

41 Installing Collar Ties

42 Adjust for Roof Racking

43 Installing Interior Walls in Attic

44 Completed Set

45 Elemental Cycle Time & Labor Productivity Set Module Strip Prep for lift Set Total 22 min. 26 min. 17 min. 63 min. 41 L-min. 54 L-min. 45 L-min. 151 L-min. Lift Roof Element 9min min. 11 min. Prep to lift roof Lift roof 14 L-min. 20 L-min. 20 min. 34 L-min. Flip Ridge Panel 5 min. Prep to Flip 12 min. Flip ridge panel 13 min. Panel 14 L-min. 27 L-min. 28 L-min. Note: Elements are not additive.

46 Cycle Time and Productivity 12:00 11:37 10:00 8:50 Cycle Time (Hr.) 8:00 6:00 4:00 2:00 0:00 4:36 6:42 man-hr ma an-hr. Crane Total Set Modules in Home

47 Opportunities for Improvement Design Potential ti Improvements Manufacturing Construction Reduced Cycle Time Reduced Site Labor Reduced Energy Use Enhanced Quality

48 Design Improvements Design product for ease of manufacturing & construction Eliminate/combine components Eliminate potential construction interferences Eliminate/redesign perimeter framing around module insets Allow knee wall to extend when roof is lifted

49 Combine Modules

50 Setting Module C

51 Setting Module D Potential Savings: Site Time.9 hr. Crane Time.9 hr. Site Labor 2.6 L-hr. Factory Labor 5 L-hr.

52 Eliminate Unnecessary Components

53 Eliminate Unnecessary Construction Interferences

54 Eliminate Unnecessary Construction Interferences Potential Savings: Site Time.7 hr. Crane Time.7 hr. Site Labor 2.0 L-hr. Factory Labor 0 L-hr.

55 Module Inset

56 Site Impacts of Design Inset Perimeter framing Remove perimeter framing Install shingles on flip Site Impacts Install siding on inset

57 Eliminate/Redesign Perimeter Framing on Module Insets Potential Savings: Site Time.8 hr. Crane Time 0 hr. Site Labor 1.3 L-hr. Factory Labor??

58 Releasing Knee Wall

59 Manufacturing Improvements Improve quality particularly roofs Move work back to the factory Shingles Siding Move some work to site

60 Improve Roof Quality

61 Lost Time Due to Roof Alignment Problems Hours Lost Cape1 Cape2 Cape3 Cape4 Ranch 2Story Home site hr. labor hr. Note: No crane time lost

62 Move Work from Site to Factory Shingles Shingle flip eaves & ridges Suggestions shift builder s cost structure Reduce set & finish cost on site Siding Add factory labor content increase module price 2 nd floor modules Should reduce total costs Add flashing & shingles around dormers on finished cape attics Insets End walls Marriage wall seal Use marriage wall gasket instead of batt insulation Install gasket in factory

63 No Shingles on Flip Eave Potential Savings: Site Time.5 hr. Crane Time 0 hr. Site Labor L-hr. Factory Labor -??

64 No Shingles on Flip Ridge Potential Savings: Site Time 1.5 hr. Crane Time 0 hr. Site Labor L-hr. Factory Labor -??

65 No Siding on 2 nd Story Potential Savings: Site Time 6.0 hr. Crane Time 0 hr. Site Labor 6.0 L-hr. Factory Labor -??

66 No Siding on Inset Potential Savings: Site Time 2.0 hr. Crane Time 0 hr. Site Labor 2.0 L-hr. Factory Labor -??

67 No Siding on End Wall

69 Marriage Wall Gasket: Factory Installed Potential Savings: Site Time.1 hr. Crane Time.1 hr. Site Labor.2 L-hr. Factory Labor -??

70 Marriage Wall Sealed After Set Potential Savings: Site Time.3 hr. Crane Time 0 hr. Site Labor.5 L-hr. Factory Labor??

71 Move Some Factory Work to Site Some cleaning Drywall finishing?

72 Construction Site Improvements Module staging locations Provide 2 module staging locations next to crane Provide pre-staging locations for modules near site Confirm staging locations with crane operator Provide good access Provide a bulldozer on site to move modules Utilize driver to strip module

73 Typical Staging for 1 Module

74 Process Flow with 1 Module Staging Location Stage Module A Stage Module B Strip Module A Strip Module B Prep Module A For Lift Prep Module B For Lift Set Module A Set Module B

75 Provide Staging g for 2 Modules Adjacent to Crane Stage Module A Stage Module B Potential Savings: Strip Module A Prep Module A For Lift Strip Module B Prep Module B For Lift Site Time hr. Crane Time.4-.8 hr. Site Labor L-hr. Factory Labor 0 Set Module A Set Module B

76 Have Crane Operator Verify Module Staging before Set-Day Two home sets (33%) were delayed because crane operator vetoed initial module staging locations Delay 1: Site time 1.9 hr. Crane time 1.9 hr. Labor 5.8 labor hours Delay 2: Site time.4-.8 hr. Crane time.4-.8 hr. Labor 1927laborhr hr.

77 Stuck! Provide Proper Access Potential Savings: Site Time.8 hr. Crane Time.8 hr. Site Labor 4.5 L-hr. Factory Labor 0 hr.

78 Stuck! Provide Bulldozer Potential Savings: Site Time.4-.8 hr. Crane time.4-.8 hr. Site Labor L-hr. Factory Labor 0 hr.

79 Use Driver to Help Strip Module Potential savings Site time Crane time Labor.7 hours.7 hours 1.5 labor hours

80 Improvement Summary Savings Potential (hr.) Site Time Crane Time Labor Hr. 0 Cape1 Cape2 Cape3 Cape4 Ranch 2Story Home

81 Improvement Summary Savings Potential ($) Cape1 Cape2 Cape3 Cape4 Ranch 2Story Home

82 Improving Fit & Energy Efficiency Accuracy of foundations Accuracy of set Accuracy of modules Gasket placement Gasket attachment to module Gasket crushing Poorly fitting gable end panels Insulation under floor pulled away

83 Accuracy of Foundation, Set & Module

84 Accuracy of Foundation, Set, & Module

85 Result of Inaccuracy

86 Result of Inaccuracy

87 Gasket Placement

88 Gasket Crushed

89 Gasket Crushed

90 Air Infiltration Through Studs

91 Gap at Joint of Gable Panels

92 Gap at Joint of Gable Panel

93 Insulation Gap in Floor Cavity

94 Best practices Radio to communicate with crane operator Factory installed lifting straps made of nylon webbing on roof panels (folds and flips), shiploose dormers, etc. OSB attic decking partially installed

95 Drywall Cracks

96 Drywall Cracks Cracks Observed Cape1 Cape2 Cape3 Before Set After Set Home

97 Any Questions

A.ENVELOPE AIR SEALING

A.ENVELOPE AIR SEALING (Page 1 of 4) Note: The Energy Efficiency Standards Section 110.7 requires that all joints, penetrations and other openings in the building envelope that are potential sources of air leakage shall be caulked,