1 / 25

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.

tab
Download Presentation

Methods of Specifying

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related