How strong are domes built with hubs?

Domes built with hubs aren't climbing frames but they are satisfyingly sturdy structures which are more than strong enough for most of their intended uses; fruit cages, garden rooms, chicken runs, children’s dens etc.

And if you feel you need more strength you can always think of the kit as a great way to get your dome built quickly and easily to the size you want before bracing to add more strength.

See below for our rough guidance on load, and ideas for adding strength.

Basic kit

No bracing or rigid panels added:

  • A point load of up to 25kg can be placed on or hung from any single hub.
  • The hubs can withstand a total, evenly distributed, load (including sticks, covering, wind, snow, etc.) of up to 200kg.

Caveat: This assumes the sticks are suitably strong; we can't account for weak or unsuitable sticks.

Adding strength

Here are a few ideas:

Rigid panels

  • If you fixed rigid panels to the frame this would make the structure incredibly strong and removes the hubs as a weak point. These could be wood; ply or OSB, or thin wall polycarbonate for example.

Bracing

  • You could also brace with metal band-strapping or wood (across sticks near the hubs), this would also remove any weakness where the hubs are concerned. Some people have cut hexagons and pentagons out of ply, placed them over the hubs on the underside and screwed them to the sticks.

Add-on caps

  • We also offer SLS 3d printed add-on caps which add a good degree of additional strength. They help to correctly align the hubs once the dome is built, and help prevent ball connectors pulling out of the hubs under tension. We have hung (85kg) from the centre hub of a 4.8m dome with those in place and hope to mould these as part of the kit in the future.

You can see the add-on caps here.

Extreme conditions!

In most normal situations / uses the dome will be fine as it comes but if you've got a covered dome and you know you're going to be facing gale force winds or very heavy snowfall, then we'd recommend bracing the dome once it's up, or going for the add-on caps.