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1
Mock-Ups: Setting the Standard
Steven P. Bentz, P.E.
Mark K. Howell
October 15, 2007
Outline (Who, What, When, Where, Why, and How)
• Presenter Background – The “Who?”
• What is a mock-up? – The “What?”
• When to do a mock-up? – The “When?’
• Where to do a mock-up? – The “Where?”
• Why have mock-ups? – The “Why?”
• How does it work? – The “How?”
• The Challenges
• The Future
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Presenters Info
• Steve Bentz– Nationally Recognized
Engineering Firm
– Project Manager
– PE, RRC, Building Envelope Consultant
– SWRI Associate Member
• Mark Howell– Nationally Recognized
Contracting Company
– Project Manager
– Historic Restoration Specialist
– SWRI Contractor Member
The “Who?”• Who’s involved in the mock-up process?
– No real surprises here….• Consultant/Designer• Owner/Owner’s Representative• Contractor
– Responsibilities….• Owner = Approval/Rejection• Consultant = Design or re-design (if it doesn’t work)• Contractor = Install, remove, re-install, match
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The ‘What?”• Mock-ups are detailed samples of work
product that are used in construction to:– Verify the Contractor’s ability to install a given
product in accordance with the specifications
– Provide the Owner or Consultant with a means of comparison by which to judge the acceptability of the installed work.
– Help the Consultant or Owner decide if the design works.
The ‘What?”• Mock-ups can take on many forms:
– Site installed samples
– Cleaning samples
– Scaled-down representations when conditions warrant
– Off-site constructed, but site-stored, comparison samples
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The “What?”
Mock-up of different limestone cleaning types
The “When?”• Ideal –
– In the design stage, prior to bidding
– Consultant needs to sell the Owner on the validity of paying for a mock-up in this stage
• Actual-– In the construction stage, as a submittal item
– Contractor is typically under pressure to get it right the first time
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The ‘When?”• Consider the following assignment:
Contractor shall provide 3-foot by 3-foot samples of exposed aggregate concrete sidewalk to match existing to Owner’s satisfaction prior to start of work.
The ‘When?”• The Consultant has specified several methods of
obtaining the finish, but the exact method is left to the Contractor– (no attempts were made during design to get a match)
• The Contractor has figured on 3 samples– (during bidding a # of samples to bid was not given)
• The Owner wants the job done yesterday– (of course)
• This perpetuates the money myth that mock-ups are expensive.
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The “Where?”• On-Site
• At an accessible location
• Adjacent to the work (but not in the way)
• Protected from damage
• Exposed to daylight and/or site conditions
• Labeled, identified, photographed, and documented for later comparison
The ‘Where?”• Consider the following assignment:
Contractor shall install mortar sample for Owner approval.
Sample 1
Sample 2
Sample 3
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The “Where?”• Contractor installed 3 samples.• The samples were installed at ground level
where they could easily be viewed.• The Owner chose sample #2 and work
proceeded.• After 1 month of work, the Owner decide
that he did not “like” the color and demanded more mock-ups.
The “Why?”
• To sort out details and determine if they can be installed as designed (confirmation).
• To demonstrate that personnel can properly execute the work (workmanship).
• To show that the color, texture, or finish of the installed work (aesthetics).
• To test components in-place*• To obtain Owner approval (submittal)
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*Important Distinction
• Mock-Up = Installed sample of work that shows workmanship, color, texture, finish, or constructability of a component mainly for approvals.
• Prototype = Full-scale system mock-up for testing involving the interaction of variouscomponents.
The “Why?”
• Helps contractors justify alternative methods.
• Helps Consultants iron out details.
• Helps Owners understand what they are paying for.
• And most importantly sets a basis for comparison and a standard for performance.
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The ‘Why?”• Consider the following assignment:
Install a sloped, standing-seam, copper cap at the 9th
and 11th floor gutters.
The ‘Why?”
• The Owner cannot see the condition.
• The Contractor cannot access the area to install a mock-up.
• The Consultant needs to know the Contractor can install the component.
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The “Why?”• The Contractor provided this
mock-up as a demonstration of their ability to work with the specified material.
• The Owner was able to see what would be constructed.
• The Designer was able to answer Contractor questions about the design intent.
The ‘How?”• The Commitment• Training personnel• Determining the construction sequence• Determining level of detail• Minimizing risk of re-submittals (unit
pricing)• Allowing time in the schedule for the
process
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“The How”? Commitment• Commitment to the Mock up
is a company cultural commitment to quality.
• Historic project for cleaning and repair to limestone and marble 25 mock ups were performed over a two week period
• Mock up checklist “our first pass”
Mock-up of Stone Repair
Prepare notice of acceptance form for Owner's and Engineer's Approval.
Schedule field inspections with Material Representative
Establish a standard of work
Select and layout ideal location for mock-up
Check requirements on preparation and field conditions
Meet Material Representative on-site
Schedule mock-up in project schedule
Select equipment/tools required for the job
Identify level of expertise and training needs
Review approved submittals
Review engineer's specifications and/or Contractor’s written procedures
CommentsNoYes1. Preplanning
FIELD SUPERVISOR:WORK ITEM:
DATE:COMPLETED BY:
PROJECT NUMBER:PROJECT:
MOCK-UP CHECKLIST
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Properly store/operate tools and equipment
Check conditions of tools and equipment upon delivery
Order tools and equipment required for the job
Identify training requirements
Select proper tools and equipment
CommentsNoYes3. Equipment/Tools
Store and handle material per manufacturer's recommendations
Check conditions and quality of materials upon delivery
Order sufficient quantity required for mock-up
Locate local and reliable supplier
CommentsNoYes2. Materials
Request written approval or notice of acceptance from Engineer and Owner
Show finished mock-up to Engineer and Owner
CommentsNoYes6. Acceptance
Perform lab and field tests on mock-up as required
Take photos before, during and after
CommentsNoYes5. Quality Control
Calculate actual production rate and material yield. Record them on log book
Stop time. Record it in log book
Perform work following manufacturer's instructions
Setup equipment and tools required for work
Set and track time and quantities. Record them on log book
Check on ideal field conditions
Review installation steps w/ crew and material representative
Choose right person or crew to perform mock-up installation
Meet Material Representative at mock-up location
CommentsNoYes4. Process
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The “How?” - Training• A mock-up can serve
several purposes:– Used as demonstration on
site to review the chink and daub technique to the crew.
– Set the level of quality expected.
– Revisited as required to compare work in progress.
– Provided the color and texture sample submittal.
The “How?” - Sequence
• Here a mock-up becomes a prototype for testing
– Individual components are installed in the sequence, each as its own mock up
– The means and methods on how the individual components come together are established
– The finished prototype can then be tested to verify compliance of the system
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The “How?” – Level of Detail• Sometimes mock-ups have to be made off-site, consider a
historic wood window restoration– Frame restored on site, sash restore in millwork shop– “Scrape and Paint Developer Quality” vs. “Strip and
Restore Museum Quality” most circumstance the specification is vague, (Frame and sash may require different level)
– The Owner is not likely to understand the various degrees of restoration possible
– Various historic review officials may be involved– The practice of “minimal disturbance” is in play– There may be hazardous materials to deal with
The “How?” – Level of Detail• Mock-up of wood window restoration in shop
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The “How?” – Minimize Risk• Contractors need to be aware of mock-up requirements
when bidding a project:– Ask questions…
• Has a mock-up been made during design?• What are the specification requirements for mock-ups?
– Qualify the bid…• If not specified, state the number of mock-ups you will be
willing to provide.• Make sure to add in time as well as money for the mock-up
process.– Suggest or offer mock-ups in-lieu of paper submittals to
protect your interests
The “How?” – Minimize Risk• How would you bid this?
– “Contractor shall provide on-site mock-up of coating from manufacturer’s standard and custom colors to match existing coating color until Owner approval is obtained.”
– No line item is provided in the Bid Form for the mock-up process.
• Cost of samples?• How many samples? Size of samples?• Cost of actual material to be used?• Timing of reviews (how long could this process take)?• Owner sounds difficult to deal with
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The “How?” – Minimize Risk• On-site color sample of coating
The “How?” – Minimize Risk• Is this better?
– “Contractor shall provide on-site mock-up of coating from manufacturer’s standard and custom colors to match existing coating color until Owner approval is obtained. The Base Bid shall include five (5) coating samples. Each coating sample shall be one square foot in area. Owner shall be afforded three days time to review and approve/reject each sample. Installation of multiple samples at one time is acceptable.”
– The Bid Form includes a coating sample line item on a per square foot basis, for each standard and custom color.
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The “How?” – Schedule• Start the mock-up process early, to avoid delays.
– If possible stage a small area for mock-up before full mobilization– Order samples of materials upon Notice to Proceed– Maintain communication with product representatives in order to
help obtain samples efficiently– Consider past experiences with specified products– Consider application conditions, set/cure times, and personnel
learning curves.– If mock ups are vague or boiler plate, set the tone by
communicating the need to better establish the expectation during the pre-planning
The “How?” – Schedule• On-site concrete repair mock-up
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“The How?” Schedule
• Pan flashing mock up for window replacement project
The “How?” – Schedule• On-site mock-up of limestone cleaning
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The “How?” – Schedule• On-site mock-up of a Masonry Restoration Project
Terra cotta Cleaning
Terra cotta Repair
Terra cotta Re-Pointing
Brick Cleaning
Brick Re-pointing
• Project Mangers and Pictures• Labeling Mock Ups to capture needs
– Job Name– Location on building– Scale– Date and Time– Finding them in Photo logs– Document not only the approved but the not approved
as well– Don’t remove your mock-up once work is underway!
The Challenges
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The Challenges• No standard process
– Mock-up requirements are likely to vary• Hard to schedule
– Pressures to start the project and finish on-time make it difficult to see the benefits in the “extra” step
• Hard to define “acceptance” and aesthetics– Owner’s approvals can be somewhat subjective
• Hard to price– Added complication of mock-ups adds costs
• Knowing too much…
The Future• Industry trends are toward more innovative ideas• New products come on the market frequently, with track
records that must be validated• The need for approval of mock-ups is not likely to become
lessened. • Frequency of prototypes being used is on the rise.• Validation programs help in the process.• Should we consider a technical bulletin on mock-ups?• How can we help standardize the process?
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Thank you!
Questions?