Mass Timber Construction as an Economic Catalyst for Affordable Housing Supply: A Cost-Benefit Analysis

This paper presents a comprehensive Cost-Benefit Analysis (CBA) evaluating the economic viability of mass timber construction as a catalyst for expanding the supply of affordable housing. Utilizing a comparative case study of a 10-story multi-family residential building, the research benchmarks a mass timber design against a conventional reinforced concrete baseline to determine the Total Cost of Ownership (TCO) and broader societal value. While mass timber initially exhibits a marginal upfront material cost premium of 6.2%, findings indicate that these costs are neutralized by a 7.2% reduction in foundation requirements due to the lighter structural load of wood products. The primary financial advantages are derived from accelerated project timelines; the mass timber structure achieved a 44.4% reduction in erection duration and a 13.5% reduction in total project duration, resulting in $183,000 in immediate soft cost savings through reduced construction loan interest. Beyond initial construction, the study identifies significant long-term operational benefits, including a projected $380,000 (NPV) in energy savings over a 50-year service life due to superior thermal efficiency. Furthermore, the research monetizes environmental externalities using the Social Cost of Carbon, assigning a $156,000 societal benefit to mass timber's carbon sequestration and avoided embodied emissions. The analysis concludes that mass timber is a superior long-term economic strategy for urban development. To overcome current market inertia, the paper proposes policy interventions, including carbon sequestration tax credits, streamlined building code reviews for mid-rise typologies, and municipal "Mass Timber First" mandates to de-risk the supply chain and achieve full cost parity.