Architects: KEY OPERATION INC.
Location: Kawasaki, Kanagawa Prefecture, Japan
Project Year: 2011
Photographs: KEY OPERATION INC. / ARCHITECTS + ReBITA Inc.
From the architect. In Japan, the lifetime of buildings is very short; they often get scrapped and rebuilt after 30 to 40 years. Recently, however, there are movements to enlarge the market for not only newly built, but also quality pre-owned condominiums, and to extend the lifetime of such residential buildings. Previously owned condominium residences have the following advantages: 1) Prices are less expensive, 2) Prices depreciate less than new construction, and 3) Conditions of the management, maintenance and residents are already known. As for asset value, prices tend not to drop for properties located in proximity to a city center with conveniences and in a good neighborhood environment. In addition, unlike units ready for sale, renovation allows a layout and interior finish to match personal tastes.
However, renovation for a pre-owned condominium unit purchased privately extends only to the proprietary space. It is impossible for a single owner to order work like seismic reinforcements personally for an entire building, even if so desired for a nearly 30-year old property. Such renovation work must be handled by a committee representing all of the residents.
The comprehensive building renovation by ReBITA takes a unique approach by purchasing an entire building of multiple dwelling units previously occupied as corporate housing or rental apartments, then refurbishing, updating the facilities, completing reconstruction like seismic reinforcements within the proprietary space, which individual owners and even the condominium committee find hard to implement, and then selling the individual condominium units. With this system, all proprietary space can be stripped down to structural concrete. It is therefore possible to implement seismic reinforcement work to all proprietary space, which would be quite difficult for a property with occupancy.
Renovation that Takes Advantage of Age
ReBITA has sold comprehensive building renovations under the ReNOA series name previously. Compared to those, the aim for ReNOA Motosumiyoshi this time was different to a large degree. In the previous ReNOA series, old-style condominium buildings were revamped to look close to new construction, but this ReNOA received a design that valued the existing conditions positively and took aging in stride to offer quality.
For instance, colored sheet steel was used as part of the facade, not only to improve durability, but also to allow graceful aging with the selected color and texture. In this context, material for the facade was studied carefully. The first proposal was an image like Taisho-era copper-paneled kanban kenchiku that used green sheet copper for diamond-shaped cladding. Subsequently, a softer design with minimal adverse impression was created, and standing seam cladding was adopted. The color was studied by looking at samples and by rendering not only green, but burgundy, black and other colors. Burgundy-colored sheet steel was ultimately selected and paneled on the entrance hall, the main stairwell, and the street-side facade to create an appearance that embodied an aged ambience.
Entrance and Garden along Sloped Ramp Form a Community
This building previously provided corporate housing and was designed with direct access to the elevator adjacent to the emergency staircase, and there was no entrance hall to the building. As a condominium building, however, an entrance hall was considered necessary, and thus added with proper security features. A community room was also created, since the entrance took on an important role of community focus to the whole condominium building. Bookshelves were installed here, so that residents could donate unused books and share them as a means to encourage communication. This common room has a large window facing the outside of the entrance. Thus, although the entrance has a security lock, the layout considered the building open in a way to people other than the residents and blending in with the neighborhood.
Since there was a rise of about one meter between the entrance ground level and the landing level of the elevator, it was necessary to create a sloped ramp for baby buggies and wheelchairs to access to the elevator. Because the ramp required a relatively large footprint, a garden was created alongside to grow plants like herbs. The entrance also gained openness with a path going up the ramp, past the elevator, and back down the stairs to the entrance hall. Finally, a roof garden was built as common space on the roof of the entrance structure, and permits residents to grow vegetables and plants.
New Approaches and Future Challenges
This renovation also addresses energy conservation. Solar cells were installed on the entire roof of the condominium building for the first time for a renovated condominium building in Japan to supply electricity to common areas and the four condominium units on the top floor. The community room provides a monitor displaying the status of power generation and sale of power back to the grid. A system called “me-eco,” which allows individual condominium units to track energy consumption, was also installed as a visual guide to promote electrical power conservation. Savings achieved with this system can be traded for CO2 credit and returned to the condominium committee.
Full-building renovations can be promoted for former rental buildings and corporate housing, but there is a forthcoming challenge of rejuvenating older condominium buildings where ownership rights are in complex relationships. Although there are examples of rebuilding led by condominium committees using the “smooth condominium full-rebuild law,” it is actually difficult to obtain the consent of the owners and to convert the ownership titles. In addition, full reconstruction costs an enormous amount of money, and burdens the environment. Thus, it will be necessary to rejuvenate 1960's and 70's condominium buildings by establishing legal systems that allow comprehensive condominium renovations in a less costly way than fully rebuilding, such as allowing real estate businesses to purchase part of the ownership rights.