2012-2015 | Copenhagen, Denmark
Client: Jeudan A/S
Type: Conservation and Restoration
The project involved the restoration of the first multi-storey car park in Denmark from 1932. The task included the restoration of the cast-concrete façades, iron windows and parking decks. Furthermore the brief called for an interior project which seeked to restore infrastructure, lighting and former functions in accordance with the existing functionalist simplicity of the building.
The overall strategy for the project was developed on the grounds of two strains of registration: A preceding mapping of the heritage assets of the building, which has been used as an estimation tool to identify the main assets for preservation. The second, a testing period to gain the necessary practical knowledge in the physical condition of the building and to establish possible methods for its repair. Together, they have formed a strategy for the conservation of the concrete which underpins its modernist heritage value.
The modernist construction and the small, canopied gas station in front of the entrance were designed by architect O. Gundlach-Petersen and were built according to modern American principles. The building was increased with two floors in 1934. The garage plant was built by the Danish engineering company Højgaard & Schultz. The car park is located in a small backyard in Dr. Tværgade in central Copenhagen.
Before the restoration, the concrete façades appeared in a soft rose coloured (plast paint?) with light grey sheet metal doorways, black metal windows and -handrails. The eastern façade had had all its window frames replaced by profile glass panes. Both decks and façade surfaces were suffering from heavy cracking and fractures due to corrosion of the reinforcement steel.
During the first phase a segment of the eastern façade, test-segment, has been renovated. This was to represent the general repairs and conditions of the remaining building. Due to a line of uncertainties related to the old concrete construction, this was seen as the best way to a gain sound experience, which was later to be used as the off set for both economical and conservation related measures for the remaining building.
The visibly damaged (skruk) concrete was cut out, the reinforcement was either replaced or treated for corrosion and the areas were recast. On the remaining surfaces cathodic protection (CP) was applied. CP is an impressed, direct current applied to the reinforcement by connecting it to a sacrificial anode. The system eliminates further corrosion and helps to retain as much of the original fabric as possible.
The relief character from the in-situ formwork, which to a great extend creates the life of the façade, was approximately reconstructed within the finish of the façade renovation. The surface was treated with a water rough render and a broom finish. The surface was then finely profiled with boards drawn along the surface to mimic the original construction method. The façade was finished in a grey paint matching the nuance of the exposed concrete, whereby the sense of the in-situ cast concrete was preserved.
The original fenestration on the east façade was restored with replicates based on documentation of the original frames on the west façade. On the west façade the window frames were to as wide an extend as possible preserved and repaired and otherwise replaced by replicas. All window frames were treated in an oxidized green high gloss paint.
The east facade before and after the restoration showing the replaced fenestration
The balconies before and after the restoration
Upper parking deck before and after the restoration
Photos by Kontraframe