Specifications

Specifications are written documents that clearly describe the required materials, requirements for the execution of the work, and workmanship expected. Generally, for small, simple projects the written specifications may be placed directly in the drawings, either typed on transparent adhesive film or in text form in CAD on a separate drawing sheet. However, for most projects, the specifications are included in a "job book" or "project manual" and issued with the contract agreements and construction drawings as the complete set of contract documents.

The job book can be a bound or loose-leaf manual and contains the technical specifications. A project manual may include the specifications as well as other documentation for the total project, such as the contract(s), bidding requirements (if needed), and general and supplementary conditions of the contract.

Specification Types

Specifications should complement the construction drawings, not duplicate them. Their main purpose is to describe the type and quality of materials and finishes; quality and method of construction and installation; acceptable testing methods; alternate provisions; and warranties and their requirements. Specifications are referred to as "closed" or "open" for bidding purposes. "Closed" means no product can be used on the project other than what is specified. Open specifications allow for the substitution of products specified, or for the contractor to suggest a number of products for the item that is specified or being bid on. There are four main types of specifications: proprietary, descriptive, reference, and performance.

Proprietary

Proprietary specifications, which are closed, call out a specific manufacturer's products by name, model or part number, and color or finish, if applicable. Proprietary specifications are the most restrictive, as they give the interior designer complete control over what is

Table 5-1 Sample Proprietary Specifications

Lounge Area

Item Quantity Description

1 3 Manufacturer #10-123, Black Leather Lounge Chair

2 4 Manufacturer # 9-321, Dark Oak, Side Table to be installed in a project. Sometimes the specifications include an "or equal" clause (sometimes referred to a base-bid specification), which means the substitution of other products will be allowed if the contractor thinks they are equal to the one specified. Proprietary specifications tend to be easier to write, as the designer needs to provide only the basic descriptive information, such as the manufacturer, product number, and finish/fabrics, as shown in Table 5-1.

If more detail is needed, the manufacturer will supply the information to the designer so that it can be incorporated into the specifications.

Descriptive

Descriptive specifications are open, and do not specify a manufacturer or trade name for the materials and/or finishes required for a project. Descriptive specifications call out in detail the materials, finishes, fabrication methods, acceptable workmanship, and installation methods. Descriptive specifications may be more difficult to write, because all the pertinent information and requirements for the construction and installation of a product must be specified. However, when a tremendous number of similar products are on the market, descriptive specifications allow the designer to prescribe the exact standards he or she wants for a project without selecting a particular manufacturer.

Reference

Reference specifications are similar to descriptive ones, insofar as they describe a material, finish, or other product based on the designer's requirements rather than a trade name. However, reference specifications are generally based on standards that are set by an established authority or testing facility, such as the American Society for Testing and Materials (ASTM) or the American National Standards Institute (ANSI).

These authorities provide minimum performance criteria for various materials and products. Reference specifications are generally short, because only the standard must be stated, and they are fairly easy to write. Chances for error are minimal, as industry standards and generally recognized methods of building are being used. However, the designer must be completely familiar with and updated on the standard and how to write the appropriate specification. Sometimes the standard includes more provisions than are needed for a particular project. Performance

Performance specifications describe the expected performance of the item(s) being specified. This type of specification is also considered open, as no trade names are included. Any item that meets the performance criteria can be used in the project. The means by which the required results are met is not specified, but left up to the contractor, subcontractor, or vendor. Performance specifications are often used for custom components when the designer wants to achieve a particular result that is not already manufactured. This type of specification can be more difficult to write, because the designer must know all the criteria expected as well as methods for testing (if required). Also, there is a risk that the designer could lose his or her original design concept along with control over the products used if it is not carefully written.

Organization of Specifications

The organization of written specifications has been standardized in accordance with the building trades. Many architects and interior designers use the specification system developed by the Contract Specifications Institute (CSI), known as the Masterformat system. This system standardizes the format and numbering of project information used in specifications and cost estimating, and organizes the job book or project manual. The Masterformat model, as shown in Table 5-2, contains 16 divisions that are based on major categories of work. Each of these major divisions is coded with a five-digit number, such as 09300 for tile. Each division, known as a broadscope, is then subdivided into narrowscope categories. The first two digits represent the broadscope, the last three digits detail the narrowscope subdivision. For example, under Painting, 09900 is a broadscope category that includes several different types of painting. Specifications within a job book or project manual could also incorporate narrowscope categories, such as 09920 Interior Painting. The level of information the designer uses depends on the complexity of the job and specifications. (See Appendix for complete listing of broadscope and narrowscope categories.)

The Masterformat system further establishes a way of organizing any broadscope or narrowscope category. Each division is broken down into three parts as listed in the Section Format outline. General information about each division, such as its scope, required submittals, warranties, etc., is included in Part 1. Part 2 includes the specific materials, finishes, and products. This part also includes what standards and/or test methods the material and products must conform to, and how items are to be constructed. Part 3 describes how the materials, finishes, and products are to be installed or applied in the project. This part also covers any preparation or examination of materials or products required prior to installation as well as how quality control will be maintained on the job. Any requirements for adjusting, cleaning, and protecting the finished work are also covered in Part 3. (See Appendix for the Masterformat Section Format Outline.) The designer or specifier (if

Table 5-2 Breakdown of Masterformat, by Construction Specifications Institute (CSI) Masterformat's 16 Divisions Example of Division 12—Furnishings

Division

1-

General Requirements

12050

Fabrics

Division

2-

Sitework

12100

Artwork

Division

3-

Concrete

12300

Manufactured Casework

Division

4-

Masonry

12301

Metal Casework

Division

5-

Metals

12302

Wood Casework

Division

6-

Wood and Plastics

12500

Wndow Treatment

Division

7-

Thermal and Moisture Protection

12510

Blinds

Division

8-

Doors and Windows

12515

Interior Shutters

Division

9-

Finishes

12520

Shades

Division

10-

Specialties

12540

Curtains

Division

11-

Equipment

12600

Furniture and Accessories

Division

12-

Furnishings

12620

Furniture

Division

13-

Special Construction

12670

Rugs and Mats

Division

14-

Conveying Systems

12700

Multiple Seating

Division

15-

Mechanical

12800

Interior Plants and Planters

Division

16-

Electrical

they are different) can select the areas of the Masterformat that are appropriate for the materials, finishes, and other products to be specified for their project and utilize this information to complete a job book or project manual where the information can be easily and reliably found.

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