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.Drawings and specifications supplied by the customer may notindicate potential problems or complications.A sketch of the project should be created during the walk through.The sketch can be used to identify problem areas when performingthe estimate.There are several key questions to ask during a site survey:" Are there plenum-ceiling areas?" Is there a staging and storage area for materials?" Are special work hours required?" Are there special safety requirements? This is particularlyrelevant in factory environments." Which walls are firewalls?" Is there asbestos in the building?" Will the customer supply spare ceiling tiles in the event ofbreakage?84 - 129 CCNA 1: Networking Basics v3.1 Structured Cabling Supplement Copyright © 2004, Cisco Systems, Inc. " Are there special labor issues to be considered?7.1.1 Requirement documentsFigure 1 Typical Building BlueprintsBlueprints are scaled drawings that provide the distance informationrequired to determine the length of cable runs, as shown in Figure 1.Blueprints should also show service outlet locations and TRs.Someblueprints also include available paths or routing information.However, routing information is generally obtained through a sitesurvey.Most structured wiring systems specify a minimum of twofour-pair cables per location and many customers specify more.Thisinformation should be duplicated in the specifications for the project.Count outlet locations and measure cable distances on a blueprint.These are referred to as take offs.Take offs require a great degree ofaccuracy since they are used to determine the material requirementsfor a bid.Many automated measuring devices are available to helpautomate the process and minimize errors.85 - 129 CCNA 1: Networking Basics v3.1 Structured Cabling Supplement Copyright © 2004, Cisco Systems, Inc. 7.1.2 Installation icons and symbolsFigure 1 Cabling Installation IconsStandard icons and symbols are used on blueprints and schematics toidentify cable runs, raceway types, outlets, and jacks, as shown inFigure 1.These icons provide a uniform method to graphicallyidentify requirements on a blueprint.7.1.3 Drawing typesFigure 1 Types of T Telephone DrawingsConstruction blueprints follow a standardized format.Drawings aregrouped according to category and are labeled with a prefix thatidentifies the category.For example, all drawings for the electricalsystem are grouped together and have the prefix E.Architectural86 - 129 CCNA 1: Networking Basics v3.1 Structured Cabling Supplement Copyright © 2004, Cisco Systems, Inc. sections begin with the letter A and all plumbing begins with a P.Telephone and data are usually grouped together and are representedon the T drawings, as shown in Figure 1.Additional drawings, suchas furniture plans, will either be found in the A drawings or in amiscellaneous category.The estimator will need the following drawings:" Site plan for an overview of the project" Floor plans" T drawings for telephone placement" E drawings for electrical reference" Furniture plans to help determine outlet placement" A drawings to discover architectural features and availablepathwaysDesign documents include a narrative about the project.Thisnarrative may describe the functionality of the cabling system.Forexample, it may indicate that the system must support 1000BASE-Tor gigabit Ethernet on twisted pair.Most design documents include trade jargon and acronyms unique toan industry or the system being installed.The estimator shouldunderstand all terms in the design document.Glossaries of terms andacronyms are available on the Building Industry Consultants ServiceInternational (BICSI) website.Design documents also specify the requirements of the system andthe types of materials that will be used.Information about the numberof cables required per information outlet or jack will also be supplied.Design documents will also describe testing specifications, labelingspecifications, and formats.7.1.4 Schematic diagramsSchematic drawings are not to scale.They are used to depictconnectivity, or the way things are connected.A typical schematicwill show the main TR or MC and the IC.It will also show the typeand size of cables between these points.Most schematics will notdetail the actual terminations at these locations or show individualcable runs to information outlets or jacks.These schematics willinclude cable runs to specific types of equipment like servers or othermajor components that are used in a project.7.2 Labor SituationsEvery cable installation company must deal with labor issues.Someof these issues can cause problems with unions.Installationcompanies must be aware of the rules and regulations that apply tounions and licensing.87 - 129 CCNA 1: Networking Basics v3.1 Structured Cabling Supplement Copyright © 2004, Cisco Systems, Inc. 7.2.1 UnionsSome projects may require the use of union labor.Unions areorganizations that represent workers.The use of union labor is morecommon for, but not limited to new construction projects.The use ofunion labor may be part of a contract.If a customer clearly states thatunion labor must be used, the contractor must use union labor.Other labor situations may dictate the job classification and the workthat is allowed.In a union environment, supervisors are normally notallowed to perform any installation work and cable installers may notbe allowed to install raceway.Sometimes, cable installers can installraceway up to a certain size or a certain length and electricians mustinstall anything beyond that.These rules are defined by a unionagreement, which may be determined by unions of different trades.7.2.2 Contractor licensesSome countries do not require contractors to be licensed.In theUnited States, contractor license rules vary for different states.Somestates require a contractor license number on all advertising, businesscards, and letterhead.Contractors that operate without a requiredlicense may be fined or lose certain rights.For example, they may notbe able to file a lien if their customers do not pay for servicesrendered.Licensing requirements include technical knowledge, businessknowledge, and knowledge of the labor laws of the state.Contractorsare responsible for knowing if they must be licensed in a particularstate or country.7.3 Contract Revision and SigningAfter all of the negotiations are complete, the contract must berevised to reflect any agreed-upon changes.The customer and thecontractor must then review the contract in detail.Contractnegotiation is a verbal event that is used to ensure that all intentionsare accurately represented in the written document.Any changes tothe contract while the project progresses are often addressed inamendments to the contract.Amendments are agreed to and signed byboth the customer and the contractor.The contract must be signed to become a valid agreement.Nomaterials should be ordered and no work should begin before thecontract is signed.A template can be created for common documents such as changeorders.These templates can be brought to the project site and theinformation can be entered during the initial meeting or awalkthrough
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