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# ACH 216 Lecture 04a (Estimating)

## by Anne Arundel Community College on Sep 23, 2009

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## ACH 216 Lecture 04a (Estimating)Presentation Transcript

• Estimating Bidding and Project Award Cost Estimating Contract Documents The Bid Package Types of Contracts
• Cost Estimating By Phase Cost Estimating Methods Quantity Take-off
• The practice of estimating is required to maintain an objective of what the project costs will be before, during and after project design.
• After the design is completed and construction documents are issued, an accurate estimate is performed which will be the bid proposal to the owner.
• Cost Estimating by Phase
• As a project develops from programming through schematic design and design development to contract documents, various items must be determined, considered and evaluated regarding their impact on a project’s costs.
• During each design phase, architects/engineers must use cost estimates as a means to communicate to the owner if the owner’s requirements and proposed budget are compatible.
• Cost Estimating by Phase
• The practice of cost estimating is broken down into four (4) phases. They are as follows:
• PROGRAMMING phase
• SCHEMATIC DESIGN phase
• DESIGN DEVELOPMENT phase
• CONTRACT DOCUMENTS phase
Architect/Engineer (or Construction Mgr) General Contractor
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• The phase is where the general contractor performs the actual quantity take-off .
• A detailed quantity take-off is the only accurate method of determining, within a high degree of precision, the project costs.
• Other methods are mere guesses.
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• A quantity take-off is a precise count of the material within the project.
• calculated in units or volume (sq. ft or cubic ft.) of material.
• The cost estimate organization should follow CSI MasterFormat Specification organization for the project.
• makes the estimate easier to divide among the estimating team.
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Preparation Steps for Quantity takeoff
• Scan Drawings and Specifications to become familiarized
• Enables estimator to get a “feel” for locations of info
• Allows estimator to notice major items that determine if more info is needed
• Mark drawings and specifications for unusual conditions or requirements
• Unfamiliar items to the estimator
• Abnormal conditions or material used
• This means that the estimator must take additional steps to ensure that quantity-takeoff and pricing is accurate
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Preparation Steps for Quantity takeoff
• Site Visit or Pre-Bid Meeting
• Note conditions to become familiarized with site
• Site access, utilities, site drainage, etc.
• Should be completed once a thorough look over of the drawings and specs has been completed.
• Drawings and specifications should accompany you on initial site visit or pre-bid meeting
• Visiting the site or attending pre-bid meeting will allow estimator to visualize conditions of site and special conditions for the project.
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Preparation Steps for Quantity takeoff
• Perform Quantity Take-off
• Determine unit costs (materials, labor, equipment)
• Obtained from vendors, suppliers
• RS Means Building Construction Cost Data
• Calculate quantities
• Multiply unit costs against quantities
• Apply variables
• Sales tax
• Commissions
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Rules of Quantity Take-off
• Measurement Taking
• Measure everything as it is, and do it twice
• Rely on the dimensions listed on the drawings
• Avoid scaling the drawings where possible
• If scaling is required, add 5-15% to the size
• Make sure scale is correct; check drawing scale
• Scale something like a 36” door to compare against
• Note locations on drawings that had to be scaled
• This could be a potential construction error
• If working for design team, it will help A/E make correction
• If working for contractor, it is a potential extra costs
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Rules of Quantity Take-off
• Take-off Every Item
• Do not leave anything out
• An omission will unnecessarily lower cost amount of estimate
• Use specifications as a shopping list
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Rules of Quantity Take-off
• Itemize take-off
• List all spaces, rooms, locations for different items
• Even if items are similar, keep them separate; they may have different installation/material costs
• Look for abnormal conditions
• Differing wall heights and ceilings that may require additional equipment or scaffolding.
• May also require additional manual labor
• Separate special labor conditions
• Items that must be performed by hand labor vs. equipment & tool labor.
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Rules of Quantity Take-off
• Check drawings against specifications
• Look for completeness, coordination & contradictions
• If working for design team, it will help A/E make correction
• If working for contractor, it is a potential extra costs
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Items to be included in Quantity Take-off (this will become Bid Proposal)
• Specification Section number and listing
• Ie, “Section 12 24 00-Motorized Roller Shades”
• Item Description or scope of work
• Be specific as possible
• Keep items separated
• Quantity
• Unit of measurement
• Each, square footage, cubic footage, linear footage
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Items to be included in Quantity Take-off (this will become Bid Proposal)
• Unit Cost
• Material
• Labor
• Equipment
• Inflation or Escalation Factor
• Should be applied if material/labor will not be ordered and installed for a extended period of time (ie. 6-24 months)
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Items to be included in Quantity Take-off (this will become Bid Proposal)
• Total Item Costs
• Multiply quantity, unit cost, inflation factor (if needed)
• Total Items for Each Specification Section furnished and/or installed by others
• Includes Subcontractors bid proposal
• Total Items for each specification division
• Total costs for divisions
• Produces a labor and material costs for general contractor
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Items to be included in Quantity Take-off (this will become Bid Proposal)
• Multiply in GC’s overhead and profit factors
• Overhead and profit may be determined by the amount of administrative work during estimating
• Most GC’s use a standard factor of 10-20% for OH & P
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Items to be included in Quantity Take-off (this will become Bid Proposal)
• Other Factoring Items
• Multiply in Project Size Multiplier , if published cost data is used
• Multiply in City Costs Index , if published cost data is used
• Multiply in Inflation Factor
• Multiply in Design Phase Contingency Factor , if published cost data is used
• Sometimes contractors will add in a contingency; amount is based upon bidding strategy & analysis
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• THESE ITEMS WILL CREATE A TOTAL SUM FOR THE CONSTRUCTION COST
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Other Information that could affect the estimate:
• 1. Job Conditions
• Economic conditions
• Hoisting conditions
• Contractor management experience
• Labor availability
• On-site storage availability
• Subcontractor availability
• Work space and staging area availability
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Other Information that could affect the estimate:
• 2. Estimating Philosophy
• No matter how accurate the estimators are, each one will determine a different estimate amount because each evaluation will be completed differently.
• Each estimator may have used different steps for estimating quantity, using different waste factors, and different labor rates
• Labor and equipment costs estimating are usually biggest source of difference between estimators
• Labor and equipment costs are based on corporate memory from past projects and are modified to present day labor wages and costs
• Cost Estimating by Phase CONTRACT DOCUMENTS PHASE
• Other Information that could affect the estimate: