Space Efficiency in Finnish Mid-Rise Timber Apartment Buildings

Abstract

As in many other building types, space efficiency in mid-rise timber apartment buildings is one of the critical design parameters to make a project feasible. Space efficiency depends on varying selection criteria related to construction materials, construction methods, and proper planning. To date, no study provides a comprehensive understanding of space efficiency in mid-rise timber apartment buildings. This paper examined data from 55 Finnish mid-rise timber apartment buildings built between 2018 and 2022 under the Finnish Land Use and Building Act to increase the understanding of which factors and design parameters influence the space efficiency of mid-rise timber apartment buildings. The main findings of this study indicated that: (1) among the case studies, the space efficiency ranged from 77.8% to 87.9%, and the average was 83%; (2) the mean values of the ratios of structural wall area to gross floor area, vertical circulation area to gross floor area, and technical spaces (including shafts) to gross floor area were found to be 12.9%, 2.6%, and 1.5%, respectively; (3) construction methods or shear wall materials make no significant difference in terms of space efficiency, and there is no scientific correlation between the number of stories and space efficiency; (4) the best average space efficiency was achieved with central core type, followed by peripheral core arrangement. This research will contribute to design guidelines for clients, developers, architects, and other construction professionals of mid-rise timber apartment building projects.

High-Rise Residential Timber Buildings: Emerging Architectural and Structural Design Trends

“…The results outlined in this paper demonstrate similarities and differences when compared to previous research efforts, such as those conducted by (e.g., [54,114]). The main findings from this study can be summarized concisely as follows:…”

“…In the context of high-rise residential timber buildings, there was a strong inclination towards using central cores. Likewise, when investigating the efficient use of space in mid-rise timber apartment complexes in Finland, the results showed that floor layouts with a square shape were predominantly conducive to maximizing the utilization of central core space [54]. Moreover, in studies related to tall and supertall structures constructed using non-timber materials, a consistent pattern of central core predominance was noted [115][116][117].…”

“…Tuure and Ilgın [54] performed an investigation into space efficiency in 55 mid-rise timber apartments located in Finland. The key findings of their study indicated that: (a) square floor layouts predominantly incorporated a central core; and (b) the sample of buildings exclusively adopted prismatic architectural designs and relied solely on the shear wall system as the structural framework.…”

“…The widespread use of prismatic shapes in architecture can be explained by the numerous advantageous characteristics linked to this design method. These qualities play a crucial role in influencing the appeal of prismatic shapes, especially in the context of constructing high-rise residential timber buildings using timber [54]:…”

An analysis of space efficiency in Asian supertall towers

“…Tuure and Ilgın (2023) investigated the space efficiency of 55 mid-rise wooden apartments in Finland. Their findings revealed that (a) space efficiency ranged between 78% and 88% on average, with a mean of 83%, and (b) no discernible scientific correlation was identified between the number of stories and space efficiency.…”