salar tahrirchi

adaptive reuse of a bank building

2nd project of my master’s program, involving the adaptive reuse of an old bank building in Dortmund, Germany, and providing all of the economic efficiency calculations.

the former Deutsche Bundesbank building is located on the south-western edge of Dortmund’s city center. the property is located directly on the Ringstraße (Hiltropwall) in the city center. on the other side of the street is the Thier Galerie, and the Dortmund shopping area is about 10 minutes away on foot. To the right of the Bundesbank is the St.Johannes Hospital, and to the left is the building of Postbank Immobilien GmbH. Behind the parking garage of our property, there are block residential buildings.

economic efficiency calculations

the current purchase price of the land was determined using the asset value method. the purchase price is made up of three factors, the land value, the building value, and the value of the outdoor facilities.
first, the production costs of the building were determined using both the gross floor area and the gross room volume. with the help of the BKI, the production costs were determined, averaged, and calculated. the current value of the building was then determined using the age depreciation factor, and the land value was determined with the help of the standard land value map.
during the course of the project, the profitability calculation was a decisive basis for decision-making, which helped determine the potential use of the building. based on the floor plans, revenues were determined that could be generated by operating the building. these are based on the usual local prices. the profitability calculation was made for a period of 15 years. It is assumed that a price increase of 1% per year will be achieved.
a counter-calculation was also done to determine the payback period. for this purpose, the expenses are determined and offset against the income, and the net profit is determined with which the total investment can be repaid. after about 16 years, the development is in positive territory.

design process

due to the location of the project and the high demand for workspaces in the city, a utilization concept similar to the Science Park in Kassel with a high co-working share as well as smaller office workspaces emerged. in the course of the design process, it quickly became apparent that the existing building with its closed facade had an unpleasant atmosphere for a coworking environment, which is in conflict with our free and inviting idea. the result was that the building should be given a refreshed design with the new function. In this case, this could be implemented with a foyer design that also invites to be used as an event space. the foyer is also intended to provide an experience of the interior and visual connection to all levels, as well as being extended outwards a little. in addition, it makes it possible to differentiate the work areas and expose them to natural light.

the basement is divided into three areas. first, are the existing technical and supply rooms of the building. then, several storage rooms, which are designated as rental spaces. all workshops and studio spaces can be rented as well. the same concept is also applied to the laboratory space. these rooms are mainly used for scientific experiments. there are three connecting corridors to the inner courtyards.

on the ground floor, the main entrance remained in place but the main facade was replaced by a glass facade in full height. the new entrance \leads directly into the foyer, which has an open space that extends over three floors. the left-wing houses a conference room of almost 700m², which can be divided into four small conference areas by mobile partition walls, while the right-wing houses the building’s administrative offices and a lounge area as a waiting and recreation area. this level is connected with further co-working spaces on the mezzanine floor and workshop and studio spaces in the basement by an internal staircase. in the rear part of the first floor is the cafeteria with approx. 330 seats.

the first floor is used as a co-working space. the difference between the mezzanine floor is mainly the larger tables, which can be joined together to form large groups.

the existing ceiling above the first floor will be extended up to the foyer in order to make the mezzanine floor usable over the largest possible area. a bridge between the two halves of the building is created, which runs through the open space of the foyer, and the existing walls will be removed except for the load-bearing structures. the existing water and sewer connections in the bathrooms area will continue to be used in place, while three kitchenettes will also be integrated. the mezzanine is designed as a co-working level where the right-wing and the main building serve as an area for individual and two-person work. for comfortable working, there are also sofas on the floor, which can be rented by the users. the left-wing houses a meeting area with two small meeting rooms, which can be combined into one large one.

the second floor contains office space, which can be rented. here you can find group rooms or areas with individual workstations. this area is also divided into two large wings by the foyer’s open space and thus can be used as a single office wing for a particular company. in addition, the bridge in the middle of the building connects the two wings.

the top floor is also a co-working space that is accessed by three staircases, which also serve as escape routes in case of fire. the glass elevator is located in the middle of the building, which makes it possible to easily detect free workspaces. the existing ventilation system was deliberately disguised as a “box”.