XML Standards for Automating the Home Building Supply Chain
The home building process requires rapid, accurate communication of complex technical information among developers, builders, trade contractors, regulatory agencies, distributors and many other participants. The speed and accuracy of transfer of this information are critical factors in building affordable, high quality homes.
As identified in the
PATH Technology Roadmap: Information Technology to Accelerate and Streamline the Homebuilding Process (PDF, 395 KB), development of a common language to allow participants in the building process to communicate electronically over the Internet is key to effecting rapid, accurate transactions. Development of Extensible Markup Language (XML) based business documents has been identified as a first, critical step in this direction.
In 2001, the lumber products industry, under the leadership of ProDealer Exchange (PDX), considered the development of these documents sufficiently important that they formed an ad hoc working group to initiate development of a standard. Since its inception and through 2002, the group has, with assistance from the NAHB Research Center, under PATH funding, made exceptional progress in developing an XML standard for the lumber supply chain.
The rapid and successful development of XML standards for the lumber supply chain serves as a sound foundation for implementing a strategy of incrementally evolving the standard to include other vertical sectors - such as millwork, fenestration, appliances, plumbing, HVAC - with the aim of becoming a single, unified communication standard for the home building industry.
The development of XML-based business documents has focused, and will continue to focus, on the further development of the business document standards including the Order Requisition, Purchase Order, Change Order, Order Confirmation, Advance Ship Notice and Remittance Advice. It will also aim at involving other vertical supply chains belonging to the home building framework, besides the Lumber supply chain.
Two separate XML models-Business and Products, were created for developing schemas representing product attributes and business messages. Purchase Order specific definitions were added to the business model and softwood lumber product attributes were added to the Products model for creating the Purchase Order schema. A similar approach was used for developing the North American OSB attributes and the Invoice schema.
A Lumber Working Group is Active
- Building material manufacturers, retailers, distributors, homebuilders, trade contractors and other agencies involved in the homebuilding supply chain are the slated users of these XML standards. Understanding needs of the industry participants is of vital importance in order to create an XML-based business model for the industry-wide adoption. As a result of this, the NAHB Research Center combined efforts with the PDX (Pro Dealer Exchange) group. This conglomeration resulted in a working group informally referred to as "Lumber XML working group" or the PDX/PATH working group.
Existing XML-based business message standards have been reviewed.
- There are several existing XML-based business standards for the various global markets. Several of these standards are either developed specifically for the Architecture, Engineering and Construction (AEC) industries or are applicable to the AEC industries due to their generic nature. Huge amount of investments in the form of cost and time have been made in the formulation of these standards. A review of these business messages was conducted in order to gauge their potential to meet the business requirements of the homebuilding supply chain.
A comparative analysis has been performed.
- The existing Purchase Order and the Invoice messages are composed of a different set of elements and attributes, based on the segment of the global market they represent. Six existing Purchase Order messages were chosen for this process, based on their potential for applicability in the homebuilding industry. The XML model forming the crux of each of these messages was then broken down into elements and attributes for comparison. The purpose behind this effort was to derive a set of most commonly used elements and attributes in the Purchase Order messages.
XML models for business and product schemas have been developed.
- A database of the commonly used business terms and product descriptions was created. This database helped in modularizing the information in a logical format and defining relationships between different business and product terms. Based on the relationships between these terms, an XML model for the business schemas and product schemas was created.
Purchase Order and Invoice schemas have been created.
- The Lumber XML working group assembled several times to document the business definitions and the product attributes for softwood lumber products. These definitions were added to the product-based XML model to create XML schemas. Business definitions relating to the Purchase Order message were added to the business-based XML model in order to create the XML schema for the Purchase Order.
- A similar approach was adopted to create the XML schemas for the North American OSB and the Invoice message. The product and the business schemas were then integrated in order to create the Purchase Order and the Invoice messages for the Lumber industry.
Schemas are available that describe generic XML-based standards for the Purchase Order and Invoice documents. These are .xsd files that can be viewed using a web browser or any text editor.
Download the .xsd files (ZIP, 45 KB)
These files can also be viewed individually below.
Content updated on 9/1/2005