The Tally application allows architects and engineers working in Revit® software to quantify the environmental impact of building materials for whole building analysis as well as comparative analyses of design options. While working on a Revit model, the user can define relationships between BIM elements and construction materials from the Tally database. The result is Life Cycle Assessment on demand, and an important layer of decision-making information within the same time frame, pace, and environment that building designs are generated. As a Revit application, Tally is easy to use and requires no special modeling practices.


The task of quantifying the embodied environmental impact of building materials involves performing a Life Cycle Assessment—a relatively new and confounding practice for many architects and engineers. The results of such assessments are typically not available to designers, as most are conducted on whole buildings and building components after construction is complete. In principle, building information modeling (BIM) ought to provide designers with the detailed bill of materials necessary to perform a Life Cycle Assessment during project delivery. But in practice, elements in BIM models often do not reflect the actual volume of materials, and this requires a more refined definition of architectural products than expected.


Motivated by the desire to leverage Revit to provide users with life-cycle impact information for building materials throughout the design process, KT Innovations, an affiliate of KieranTimberlake, began developing Tally in 2008. In response to growing industry awareness of life-cycle considerations, KT Innovations partnered with Autodesk Sustainability Solutions and thinkstep (formerly PE International) to create a comprehensive, easy-to-use tool that brings accurate life-cycle data to the design process.