CU29, the chemical symbol and atomic number of copper, or to be more precise the crystalline structure of the same, was the inspiration behind this façade designed by Foster + Partners. When approached by their design team in Summer 2014, Priedemann Facade Experts knew that there is a challenge of their calibre awaiting.
Cover image: The crystalline building envelope looks light and allows plenty of daylight into the building but protects against too much sun. (Image by RMK/Schueco)
After a thorough study of RMK’s work practices and expectations, Foster + Partners came up with a two-storey facade design, providing an atrium like communication zone between the floors. Out of the sophisticated office concept as well as the unique design of the building skin grew a challenge our teams never faced before, although it was not our first assignment in the Far East.
When we came onboard, a lot of parameters had already been set: two storey high façadeelements by 10 to 12 m in height and 6 m in width and the crystalline design. The existing 3D models already contained the exact inner and outer shape. All we would propose & design, be it the load bearing structure, the profile and system design, glazing and panelling plus structural and building physics had to fit into that shape. Furthermore, up to 12 profiles joined into one single point at the element edges and we had to ensure not to create any leakage, so we needed to deal with tenths of millimetres and, at the same time, paying attention to element weights of up to 12,000 kg.
To do so, we came up with a hybrid design, a steel tube structure bearing the load and accommodating the building tolerances in connection with slim, precisely extruded aluminium profiles to hold sealings and glazing.
To put this idea to reality, we started setting up a parametric model from scratch. This enabled us to cut the structure virtually in any angle and direction to check the interfaces between the various parts and pieces. Later we enhanced the model to verify if all parts would be reachable during the manufacturing and assembly phase.
Above: As virtual reality reached its boundaries, we just printed out the profiles in 3D for a first real assembling (by Priedemann)
But we quickly reached the boundaries of virtual design, leading to the next logical step; a 3D printed model to get a ‘real life’ corner. Now we were able to test how one could bring all together.
Sustainability by using local sources
Later on, a decision was made by the Russian client. He stipulated local resources and materials to be used instead of carrying what was already available half around the world. From a sustainable perspective, there was no doubt about this requirement, but one feared about the design outcome, especially in regard to its complexity.
That caused the suggestion to move as the appointed façade consultant from the planning to the execution side and switch from consultancy to engineering. By doing so and following the whole architectural design intent until it’s final completion, another benefit occurred; while serving the façade contractor, the architect retained the option to change or adjust details whenever necessary.
Now our words had to be proven by actions, we had to build what we designed. In a first step we had to familiarise ourselves with local glass and steel codes and standards, to learn about the local aluminium extrusion and above all to find out where the strength and weaknesses, opportunity and threats on the fabricator side would be. That was essential to understand and support the appointed manufacturer to deliver not just a façade but a masterpiece.
Therefore, we shouldered full responsibility for the entire engineering job from system design via shop- and fabrication drawings, test and visual mock up planning until the final hand over documents.
Once the planning was completed down to the last screw, the next step was to cope with the logistic aspects. The elements were far too large and heavy to be fully assembled in the factory and the idea of a site hangar was born where the sections should be brought together.
But how can one assure that the right pieces come in the right sequence to the right place? We looked to Sweden…. Right, that’s where we found our solution… How would IKEA do it? We prepared a manual following IKEA’s look & feel explaining step by step the sequence how to assemble each piece, one for the factory respective site hangar and a second for the installation.
Dealing with giant elements and extreme climate
The element dead load and their sizes would have been enough of a challenge already; actually a single bracket was as heavy as standard elements somewhere else. The test mock up didn’t fit into the standard facilities, two racks had to be linked together and the roof to be lifted. Add to this -35°C in Yekaterinburg as we witnessed the visual mock up on site.
For the building physics calculation, we had to consider temperature differences between -40° up to +35°C and a winter period which can last up to 6 months. Consequently, a triple glazing was planned but also the thermal expansion of steel, aluminium and stainless steel had to be taken into account. Looking at an element height of 12 m and considering a 75°C temperature difference, aluminium can expand by 18 mm. That’s quite a lot considering that the sealing system should be functional in summer as well as winter timer.
By taking over full responsibility, from detailed design all the way to the installation on site, along with using the latest digital 3D tools and not to forget a lot of teamwork with years of knowledge, we were able to deliver the desired result and successfully complete this project.
This article was originally published in IGS Magazines Autumn 2020 Issue: Read the full Magazine here for more thought-leadership from those spearheading the industry
Author: Andreas Beccard, CCO & Business Development UK at Priedemann Facade Experts
Andreas learned the carpentry trade and later studied interior design in Wismar and construction management in Augsburg. He worked as an architect in various offices and met Priedemann at HPP in 2001. Since then he is fascinated by facades and has not only managed many facade projects at Priedemann Facade Experts, but has also become part of the company’s management.
From 2015 to 2017 he set up an Priedemann office in London to come closer to the company’s UK-and international clients. Andreas is responsible for the company`s content management and he loves to come on board in the early project stages as for concept design or architectural competitions.