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Methods of Specifying

Methods of Specifying. ACT 380. Objective. Recognize the language, proper preparation, and appropriate situation for the four methods of specifying. 4 Methods of Specifying. Descriptive Performance Reference Standards Proprietary *****See pages 5.58 through 5.7. Descriptive.

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Methods of Specifying

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  1. Methods of Specifying ACT 380

  2. Objective Recognize the language, proper preparation, and appropriate situation for the four methods of specifying.

  3. 4 Methods of Specifying • Descriptive • Performance • Reference Standards • Proprietary *****See pages 5.58 through 5.7

  4. Descriptive • Defines exact properties of materials and methods of installation without using proprietary names • Is prescriptive – the products and processes are specified – not the results • Once widely used – but as projects have become more complex and better reference standards are available – used less

  5. Example Descriptive Method • A concrete mix of four-parts coarse aggregate, two-parts fine aggregate, and one-part cement with a 0.5 water-cement ratio is specified • It is implied that “ a performance strength of 3,000 psi after 28 days” will result in this mix – but is not specified • If concrete conforming to this mix were supplied- but failed - the contractor would not be held responsible

  6. 5 Steps to Preparing Descriptive Spec • Research available products • Research critical features needed • Determine which features are best specified and which are best shown on the drawings • Describe critical features (min. acceptable requirements) • Provide specific information about submittals, testing, and other procedures needed to ensure product meets needs. Be realistic in doing this.

  7. Performance • Specifies the required results • The criteria by which the performance will be judged • The method by which all this can be verified • The contractor may choose the materials and methods as long as it complies with the performance criteria

  8. Problem with Performance Spec • If incomplete…it can result in major loss of control over the quality of materials, equipment, and workmanship • Much more time consuming than other methods of specifying

  9. Performance vs. Descriptive • In a simple project one is requiring the use of a “ceiling hanger”. Performance requirements in this case can easily be incorporated by: • Performance spec – “non-sag” AS OPPOSED TO: • Descriptive spec – “straightened No. 11 wire, tightly wrapped two times’ • See page 4.43; fig 4.8-A

  10. Reference Standards • Requires a product or process be in accordance with an established standard • Typical standards encompass: • Basic material standards (ASTM C 33-93 standard spec for concrete aggregates) • Product standards (ANSI/AAMA 302.9 specs for aluminum windows) • Design standards (ACI 318 – building code requirements for reinforced concrete)

  11. Reference Standards con’t • Workmanship standards (ASTM E 737 standard practice for installation of storm windows, replacement….) • Test method standard (ASTM E 34 chemical analysis of aluminum and aluminum alloys • Codes (ANSI/ASME A17.1 safety code for elevators and escalators

  12. Reference Standards con’t • These are incorporated into the specification by referring to a number, title, or other designation • Realize that standards usually refer to minimum requirements

  13. Guidelines for Using Reference Specs • Know the standard • Some reference standards may contain provisions. Theses provisions may be voided in a footnote or subsequent paragraph unless specifically stated in the specifications • Some standards include several categories. i.e., ASTM C 150-89 standard spec for portland cement actually covers 8 types of cement. If not stated which one…the least expensive may be used…may not meet project requirements

  14. Guidelines for Using Reference Specs • Incorporate the standard properly – • Because the reference standards sometimes refer to workmanship, this could cause conflicting or duplicate statements with Conditions of the Contract or Division 1. The solution: Include a clause in the Supplementary Conditions stating that the requirements of the Conditions of the Contract govern over the requirements of reference standards

  15. Guidelines for Using Reference Specs • A complete designation includes: name of the issuing organization, number of the standard, title, and date of issue • Dates can be a concern because periodically standards are updated Solution: in Divsion1, Section 014200 – References include a statement which is similar to this, “the date of the standard is that in effect as of Bid date, or date of Owner-Contractor Agreement when there are no bids” • Enforce the requirements of the standard

  16. Proprietary Spec • Specifies actual brand names, model numbers, and other proprietary information • Prescriptive (descriptive method is other one) • Federal and public projects forbid the use of this method except in a few special circumstances • 2 main types:closedand open

  17. Closed Proprietary Spec • Only one product is named • Several products may be named as options • NO substitutions

  18. Open Proprietary Spec • Prices are requested for specified alternatives • Substitutions and cost adjustments may be proposed by the bidders • Products are allowed as substitutions after approval by A/E

  19. Advantages of Proprietary Spec • Close control of product selection • Preparation of more detailed and complete drawings based on precise information obtained from manufacturer’s data • Shorter specifications and reduced production time • Simplification of bidding by narrowing competition and removing product pricing as a major variable

  20. Disadvantages of Proprietary Spec • Elimination of narrowing of competition • Requiring products with which the contractor has perhaps had little or bad experience (slow delivery, lack of proper technical services, difficult payment arrangements) • Favoring certain products and manufacturers over others

  21. Simplified Example of Methods of Specifying— Class Exercise • For this very simple example we will use a common fruit --- an APPLE. • How would you specify an apple using the following methods? • Descriptive • Performance • Reference Standards • Proprietary

  22. Descriptive 2-1/2 INCHES to 3 INCHES DIAMETER MEDIUM RED TO RUST COLOR CAPABLE OF MEETING TRADITIONAL COOKING OR EATING CLASSIFICATIONS

  23. Performance TASTES GREAT

  24. Reference Standard USA Brand, USDA GRADE # 1

  25. Proprietary JONATHAN

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