Purpose and Scope

The Contract Pay Items schema in this business area is the first step in addressing contract pay items.  It will include pay items (id, type, description, units of measure) and funding source as well as a list of contract pay items and their respective funding sources on a given project from the existing aecXML  Infrastructure Working Group schema.   Additional information to be added will be quantity and pricing for each pay item for a given estimate of a specific project or proposal.

A UML semantic model of pay items, projects, funding sources, and proposals will be created to show the attributes of and relationships between these entities and to gain consensus on their meanings.  An XML schema will then be created.  For those areas of overlap with aecXML, we will try to be consistent with the existing aecXML schema to minimize the impact on existing aecXML users.

The existing aecXML schema is useful for designers to obtain information about possible pay items available for use on a project.  It allows the designer to specify which of these will actually be used on the project.  The next step in the design process is to then determine the amount of each item that will be required to construct the project.  Addition of quantity to the schema will enable this information to be captured and then communicated to the estimator who will determine the estimated cost of the project, the plans developer for inclusion in the contract documents, the contract administrator for inclusion in the bid proposal, the contractor to help him develop his bid and schedule the work and materials needed during construction, the inspector to keep track of work completed versus planned, finance for project billing, and maintenance and operations for managing the constructed facility.

By adding project/pay item based cost information, the schema will support additional steps in the design and subsequent processes.  Various costs are appropriate, including the designer’s initial estimated cost on pay items for an individual project, an estimators estimated cost per item on the project and for a proposal which may include several projects, each contractor’s pay item bid price, the awarded contractor’s price, and any price adjustments made by change orders after the project is let.

The schema will be extended further by the construction business area to add bid package information and to support the tracking of installed quantities during construction.

The design business area Contract Pay Item schema should be relatively small in size, considering the minimal number of entities involved, their lack of complexity, and the work already done by the aecXML Infrastructure Working Group.  It should be the first one scheduled for development under this project, to allow the construction business area time to extend it.  We therefore propose that this schema be developed in accordance with GML.  The minimal use of spatial information make it an excellent candidate to demonstrate the applicability of GML to non-spatial as well as spatially located entities.

Base Schema/ Standards

Existing schema and/or standards that this will be based on include:

·         aecXML

·         ISO TC211 19136 Geographic Information – Geography Markup Language (GML)

Resource Documents

·         IAI aecXML Domain Committee, aecXML.xsd

·         ISO, ISO/TC 211/WG 4/PT 19136 Geographic information – Geography Markup Language (GML), ISO CD 19136, February 7, 2004.

·         Ron Lake, David S. Burggraf, Milan Trninic, and Laurie Rae, Geography Mark-Up Language, John Wiley & Sons, Inc., San Francisco, CA, 2004.

Sample Applications

Proposed applications to be developed to demonstrate the use of this schema:

·         .NET, web-based application whereby the master pay items for quantity takeoffs is downloaded via XML from estimating software.  The estimating software contains the master list of allowable contract pay items with information about each, such as id, type, description and units of measure.  The designer selects from this list those items which will be needed on his project and an XML subset is produced.

·         NET, web-based application whereby XML quantities data will be displayed for review purposes.  Data for review includes pay items, descriptions, units and quantities.  A field for price will be included on the form for user input.  Updated XML data is then created for subsequent uploading to estimating systems.