Wooden Additional Floors in Old Apartment Buildings: Perspectives of Housing and Real Estate Companies from Finland

Abstract

This paper examined various stages and advantages of wooden additional floors from the perspective of Finnish housing and real estate companies through interviews with professionals involved in these projects. Main findings highlighted: (1) commercial conditions should be carefully analyzed for return on investment; (2) city plan change and the presence of a potential contractor and an expert were generally considered important issues; (3) considerations regarding city planning, parking spaces, load-carrying capacity, and new building codes were highlighted as critical factors for feasibility study; (4) existing building regulations and building rights regarding the subscription fee and tax issues should be considered during project planning; (5) city plan change and building rights with different tendering conditions were reported as important parameters in implementation planning; (6) an efficient flow of information between the parties involved was vital to the successful progress of the construction phase. Wooden additional floor construction, which requires commitment, investment, and cooperation between interested parties, has great potential regarding construction technology and contracting mechanisms. Additionally, this sustainable approach has many advantages concerning the environment, economy, energy efficiency, and aesthetics. In this sense, it is believed that this study will contribute to the diffusion of wooden additional floor construction in other countries besides Finland.

Residents’ Attitudes towards Wooden Facade Renovation and Additional Floor Construction in Finland

“…Surveyed apartment building owners’ attitudes towards wooden additional floor were generally positive (the total occurrence of “positively” and “partially positively” options) (63%), while about one-fifth (21%) of respondents had a negative view of this—see Figure 8 . This high rate of positive attitudes may be due to the economic advantages of additional floor construction, for example its revenues can be used to finance the renovation of the existing property (renovation of an elevator to improve the accessibility and commercial conditions of the building) [ 17 , 62 ].…”

“…Due to the lack of literature, it has not been possible to conduct a comprehensive discussion to provide information on the similarities and differences of Finnish residents’ attitudes with examples from other countries, as reported by Karjalainen et al [ 62 ] in the study on wooden additional floor construction from the standpoint of Finnish housing and real estate companies.…”

“…Moreover, there are very limited studies on wooden additional floor construction, and these are not perceptual studies. Among them, Karjalainen et al [ 62 ] scrutinized different phases and advantages of wooden additional floor construction from the perspective of Finnish housing and real estate companies through interviews with professionals involved in these projects, while Soikkeli [ 17 ] presented the research project aiming to develop an industrial scale, economical and efficient concept for renovating, expanding, and adding floors to apartment blocks. Therefore, there is no study in the literature on the perception of the residents about wooden facade renovation and additional floor projects.…”

Wooden Extra Stories in Concrete Block of Flats in Finland as an Ecologically Sensitive Engineering Solution

“…Extra story construction has many benefits such as [41]-(i) from an environmental point of view, as an ecologically sensitive engineering solution, renovation and improvement operations with extra stories were more than 20% lower in carbon footprint compared to demolition and new construction [39], thus it increases the income of the property owners, resulting in a beneficial development of the building stock; (ii) from a financial standpoint, its revenues can be used to finance the renovation of existing property, such as the renovation of an elevator (Figure 5), to improve the building's accessibility and commercial conditions; (iii) in terms of energy efficiency, extra story construction does not significantly increase the overall energy consumption of the building, although it significantly increase the total floor area and as passive energy efficient structures, it can significantly improve the energy efficiency of old buildings, especially if the upper floors have not been renovated for a long time; (iv) from esthetical point of view, it can significantly affect the architectural features of the building and improve the facade appearance; and (v) from a social (sustainability) point of view, that is understanding people's needs and desires (e.g., [42,43]), extra story construction that meets the demands of residents, where Finnish suburban residents generally have a positive attitude toward this sustainable solution [44]. On the other hand, according to some studies in the literature (e.g., [45][46][47]), the lack of cost-competitiveness of wood compared to conventional materials such as steel and concrete can be considered a disadvantage of wood in the construction of extra stories.…”

Comparative Study on Life-Cycle Assessment and Carbon Footprint of Hybrid, Concrete and Timber Apartment Buildings in Finland

“…In the literature, many studies focus on the technological aspects of EWPs, their use in construction, and different building solutions [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ]. Several studies address wood as a structural material in buildings from the perspectives of key professionals (e.g., [ 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 ]) and consumers or residents (e.g., [ 60 , 61 , 62 , 63 , 64 , 65 ]).…”