Built in 1882 on a street lined with century old terrace houses, the architecture for the renovation of this inner city house had two elements: create an amazing lounge room and, like most renovations for houses of this era, create a connection to the rear yard. Important to understanding the context of these factors are the two large trees whose silhouettes rest on the rear façade. The architectural response for the rear elevation was based on a grid of 6 two-by-two-metre squares. Just as this façade is visible from the outside, the façade is completely visible, uninterrupted, from the inside. The internal room from which this is visible is the main lounge area to the house, affectionately referred to as the ‘Great Room.’
The rear façade consists of alternating western red cedar solid and glazed elements as a response to the connection to the rear garden – and the trees. It was after we were presented with this narrative, that we were presented with the true challenge. Just as the two adjacent ceiling voids of the MUSAC cut to an impossible point, Andrew and Anita wanted the two upper glass panels to touch at their corners.
They knew it was impossible. But they also knew that asking the impossible—being aspirational—would guide the best outcome. Asking the impossible will send a message about what the real desired outcome is.
As I mentioned, the precedence was the MUSAC. In the foyer of the MUSAC, two large skylights join. There is positive space, expressed in white, where the light from the skylights reflects off the vertical surfaces intersecting with a negative space, expressed in black, where the light is in shadow. At the junction of the two adjacent positive spaces, there appears to be no separation between the two, they seem to touch. They appear like two boxes just touching at the corner, the slightest movement of these boxes and light would break through.
The MUSAC Contemporary Art Museum building designed by Spanish studio Mansilla + Tuñón has uplifted the city of Lèon since 1 April 2005
In the MUSAC, the vertical corners of the adjoining skylights taper to a point. The taper is vertical; so the junction is in the horizontal plane. The boxes are only touching at this lowest point. This allows structure behind the cladding to link the boxes together down the length of the box.
The challenge at the 3X2≠3+3 was different. The taper is horizontal and the junction is in the vertical plane. The MUSAC uses gravity to its advantage, 3X2≠3+3 is fighting against gravity. With the MUSAC the junction was vertical, running with gravity, the 3X2≠3+3 was not only horizontal, fighting against gravity, but on the external façade subject to wind. Turn this sideways creates structural complications. The loads are different. Another important diffence is that taper at the MUSAC was several metres long. We were trying to do the same trick at 3X2≠3+3 in a few hundred millimetres.
The original solution was to run a column from the ground up to the roof through the middle of the façade. This column was initially sized as a 200 x 100 RHS. With 100 as the width of the column. This means that the windows, not including the frame would be 100mm apart. The question was then, can this be made thinner? Because this column was in compression, and susceptible to buckling, it needed to be 100mm wide.
The initial proposal, with a central, full height, vertical column.
The question then arose, if it is the compression which is driving such a big size, can we put the column into tension. And that is where the solution came from. Rather than have the column running up from the ground, why don’t we have it hang from the roof. We landed on the solution: the plate hanger. This plate hanger was the key moment. Steel is great in tension. Steel in compression or bending needs to be larger. But the hanger was only in tension and that is the key. It could be thin. This allowed the glass to come close together.
The intial proposal where the horizontal transom aligns.
This hanger offered another opportunity. The transom running across the facade was initially proposed to be continuous from one side to the other. The introduction of the hanger allowed for the transom to be offset where it joined the hanger. This offset of the transom allowed the adjacent glass panels to align top and bottom.
