6-story point access block with wikihouse?

Using WikiHouse
1

Hi folks,

I am new to the WikiHouse community and I am exploring a housing project and the possibility of designing it via Wikihouse.

The project is a 6-storey multifamiliy building.
Point access block (i.e. single shared staircase, single shared elevator).
The ground floor would be either commercial or residential units.
All other floors would be residential units.

I have some questions about this.
If you can help, I greatly appreciate it!

  1. Why are Wikihouse designs currently limited to 3 storeys?
    Could the designs work for 6 storeys if the lower floors were constructed with another material other than the timber product that is standard for Wikihouse?

  2. Has anyone used Wikihouse to design similar buildings? Even if only 3 storeys.

Thanks in advance for your advice.

Take care,
Niall

2

Hi Niall,
that’s exciting!
Some thoughts from an engineering perspective if helpful.

a) Structural stiffness: The design is limited to 3 storeys because of flexibility constraints under horizontal loads. The stiffness of WikiHouse is similar to light timber frames, and both systems are not really suitable for high storey structures. Even stiffer systems like cross laminated timber and Glulam might struggle to meet stiffness criteria in high storey buildings. A possible solution is to mix structural systems, for example by having a concrete lift shaft/stairs to provide extra stiffness to horizontal loads. This is a nice example in my opinion Brock Commons Tallwood House | Campus as a Living Lab
(please note that Vancouver is also very seismically active, so they have to meet earthquake design regulations too)
2) Fire/acoustic can also be challenging. When you have multi-families and commercial units, fire/acoustic requirements become more challenging to meet. In particular the more complex the structure, the more exponentially challenging the fire strategy.

I am sure that there are design solutions that can be worked out. However, perhaps there are better systems available for this type of projects?

By the sound of your description, I would consider Cross Laminated Timber (combined if needed with a concrete lift shaft) .

Hope that helps!
Gabriele

3

Hi Gabriele,

Thank you for these insights!

I will simplify it initially to all resi based on your point that commercial units often have very different fire/acoustic requirements to residential units.
What exactly are the key differences in requirements, usually?
Possibly they can be folded into a common universal design?

I’m very enamoured by the Wikihouse idea of ‘printing’ the parts locally and assembling them locally or on-site.
It would be great to figure out to what extent the Wikihouse model can evolve to support that.

Could the first (3) storeys be made from CLT that is ‘printed’ with local CNC machines?
Then the core lift shaft in concrete and the upper (3) storeys made with conventional Wikihouse timber material?

How do other high rise CLT buildings meet the required stiffness criteria?

Take care and thanks again.