Cost-Effectiveness of Mass Timber Beam–Column Gravity Systems

Abstract

The cost of mass timber buildings is a major point of interest to building developers and architects because it often dictates the fate of proposed mass timber projects. Cost estimation for mass timber construction has several unique aspects that differ from those of steel, concrete, and light-framed wood buildings. With the new building categories (Types IV-A, B, and C) introduced in 2021, it is important to look at cost implications of both the new and existing types (III-A and -B and IV-HT) and cost sensitivity to key design features. An automated design and cost estimation algorithm for mass timber gravity systems was developed. The algorithm includes an automated member selection and design procedure that implements strength and serviceability checks. Fire rating and design requirements were included. The final cost calculation includes material costs of wood, connection hardware, fire protection, and an estimation of installation cost. The details of the proposed algorithm are presented in this paper, together with scenario analyses on archetype design using different mass timber categories.