Pre-fabricated wooden elements preserve historic Kaifu-Bad bath complex

Kaifu-Bad, the oldest swimming pool complex in Hamburg, has been subject to a major renovation project which has used pre-fabricated wooden elements by Metsä Wood. 

Kaifu-Bad is a protected monument built originally in 1895. Prior to the renovation, the complex had been closed for several years due to its unstable roof, which was in danger of collapsing. 

The renovation project posed several challenges for architects MRLV and WTM Engineers: the need to respect the protected design, tolerate the salt-water baths and high levels of humidity and meet modern sustainability standards.

A number of Metsä Wood’s pre-fabricated wooden elements were specified as a solution.

Protecting against humidity and corrosion

A major part of the renovation saw one of the pools converted into a salt-water bath. This posed an issue for the architects as, due to the water’s salt content of 6%, a steel solution would be exposed to high levels of corrosion.

Therefore the old roof truss needed to be replaced with a steel-free construction – the whole renovation was completed without metal joints.

MRLV specified Metsä Wood’s industrially manufactured Kerto-Q wooden trusses as the primary material as it could handle the changes in temperature as well as the corrosive effects of the high humidity and salt water.

By specifying a pre-fabricated material, the project also succeeded economically: all the wooden parts delivered ready to install on site, resulting in significant savings in construction time. 

Kerto LVL (Laminated Veneer Lumber)

Throughout the Kaifu-Bad renovation, the Kerto products were used in a variety of different applications including beams and panels.

Structures created using Kerto proved strong and dimensionally stable. For instance, despite the 14m long span, the main trusses could be manufactured in a thickness of just 134mm. 

The Kerto-Q panels also preserved the historical barrel shaped vault by allowing an arched cut off the bottom of the trusses. The 69mm thick Kerto-Q panels used for the roof shell paneling also stiffened the roof structures and stabilised the original brick walls against wind loads.