the Carpentry Way: Just Like an Erector Set                                                          

Just Like an Erector Set

    
Erector set, for those unfamiliar with the reference - a building toy similar to the English Meccano, sold in the US. It's not Lego:


While both Meccano and Erector Set (I had various sets and parts from both as a child) employ metal components which fasten together with bolts, I recently came across an interesting structure designed by Japanese architect Shigeru Ban that was reminiscent somehow, though comprised largely of wood. This is the largest timber structure - 7 stories - in all of Switzerland, and is quite an interesting design from a number of viewpoints.

Here's Shigeru Ban, who also happens to be the 2014 Pritzker Price recipient for Architecture:


He apparently always dresses in black.

This is the Tamedia Building he designed:


Another view, showing the building's non-square footprint:


The structure was completed in 2013. The company who constructed the wooden frame is Blumer-Lehman, which has been in business in Gossau since 1875. Here's a picture from their company history page, showing a slice of the early days:


The above image, in terms of technology, perhaps well encapsulates the ideal for more than a few North American timber frame companies these days, if I might be a bit cheeky. Blumer Lehman has moved along a bit. They are a big company, and build many types of wooden structures, from offices, residence, modular structures - even huge wooden grain silos.

It's when you see the Tamedia building peeled open, as it was when under construction, that the unique framing becomes clear to see:


The parts of the building are akin to skeleton bones, enlarged at the ends, slimmer in the middle. Elliptical section horizontal rods pierce the nodes:


This is where attention to detail pays off:


As the face of the building turns the facet, we see a post with a parallelogram-shaped section, and the dog-bone shaped beams are stretched, as it were, to fit the post. Neat!

A closer look at some of the framing details. The elliptical gluelams are high quality and are not as aesthetically objectionable as many I have seen:


 It's an intriguing connection - the tenon on one end fits to a corresponding mortise on the next elliptical beam:


 Here's a shot which shows the splice joints between elliptical beams a little better:


The parts are well fitted - as I understand, CNC machinery was employed:


A node:


In this picture, if you look at the lower end of the posts which the workers are sitting atop, you will see a Japanese type of compression splice, jūji-mechigai-tsugi:


In case you didn't spot it, look for a vertical splice that looks like this:


I'm not normally too excited about glue-lams in general, but I find the ones used in this structure to be attractive. A big plus in regards to glue-lams is that they can be laminated out of completely dry material. And I don't think you could do seven stories in solid timber without recourse to using some really large trees.

In case you were thinking that glue-lams are not the way the Japanese would do it, you might be surprised to find that a lot of glue-laminated timbers are used in the poshest of sukiya teahouses. Here's an example, this post faced with hinoki:


Laminated ceiling rods:


Anyway, the Tamedia building's used of a wooden frame along with the usual glass, steel and concrete creates some aesthetically pleasing interior spaces:


Roof area:


It must have been fun fitting the ceiling mateiral in and around the timber connections:


In this one you can see one of those parallogram-shaped posts to the left - chunky!:


All for today. How do you like this structure? It's a lot more environmentally friendly than most 7-story urban structures, both in the construction's environmental footprint and in it's energy efficient operation.