About ridge beams

Hello everyone,

We have received a couple of questions about the ridge beam connection detailing. Even though we do not have a final series of blocks for it yet, we thought it might be a good idea to share some work in progress just in case it might be useful to the community.

What is a ridge beam?

It is the beam at the top of the roof. It collects the loads bearing on the roof (e.g. snow), and it transfers them into the side walls supporting it.

Do you need one in your WikiHouse project?

Most likely. We see the ridge beam as the easiest solution. The alternative is to use a tension element (such as a cable, or a timber element) on each couple of roof blocks. This might reduce the liveable space compared to the ridge beam, therefore we think it might be less appealing.

What is the ridge beam made of?

Solid timber is likely to be the easiest solution. It can be either Glulam, Laminated Veneer Lumber or I timber joist. Glulam and LVL offer higher capacity/stiffness than I timber joists, so these last might not be strong/stiff enough for longer spans. There are calculators available online to estimate the likely cost of a solid beam, such for example this on here Glulam Beam Price Calculator

What about the dimensions?

It depends on the size of the roof and the span that the beam has to cover.Talk to your structural engineer about it. This is actually bread and butter for her/him.

How does the ridge beam connect to the WikiHouse wall?

There are probably different ways of doing this. A possible solution is to create a sitting bracket for the ridge beam to sit on. It also would be good to provide a connection (for example by using a small plate with screws) that prevents the ridge beam from uplifting and sliding. This is necessary because wind loads will try to uplift your roof, and we should secure that.

3D models of the sketches available here Ridge beam – Google Drive

Hope this might help.


That is dood Gagbriele but some fixing down for cyclones would be useful here and and how does the Roof Blocks and Barge beams connect to the Glulam ridge beam?
I cant t make it to the broadcast as tonight as it will be3.00/ 4.00AM here in AU, depending on your summer time. Will catch it on YouTube later; maybe in the future it would be good swap months times to your mornings would help some other time zones? How are those SB Blocks tests going?
All the best, Graham Osborne

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Hi Graham,
excellent questions:

  1. About wind loads, a possible way is to use a steel plate with screws (the blu element you see in the drawings). However, I am not sure about how much stronger a cyclone uplifting force is compared to typical storms. The capacity depends on the amount of screws that you use, so it needs to be adequately designed based on the expected wind force.
    We provided a video here, maybe ithelps WikiHouse ridge beams explained - YouTube
  2. About the connection with floor blocks, please have a look at this: Connecting ridge beams to roof blocks - YouTube

Thanks for the feedback. It’s a bit tricky to coordinate the live events across different time zones, but let’s see what we can do. Hopefully you can still access the recording in the meantime.

About the testing, there is quite a lot of work going behind the scenes. The team at Imperial is working hard on preparing the experimental setup (paint the specimens, install the controlling instrumentation, implement the loading protocol in the actuator, calibrate the potentiometers, sort out the cameras and lights, etc). This is actually the most delicate part of the experiment, and we want to make sure that everything is under control. Fingers crossed we will be able to share something by end of the month :crossed_fingers: