topic Openings, Penetrations and Fire Collars in Libraries & objects

Openings, Penetrations and Fire Collars

Matthew Johnson — Wed, 15 Oct 2025 06:54:20 GMT

Working with our service engineering colleagues we often need to leave holes in slabs/walls/roofs for their services to pass through. In most cases these openings need a fire collar to maintain the fire rating of the element being passed through. These fire collars are a standard off-the-shelf item that comes in set sizes, have a set thickness and also requirements for clearances from the next penetration.

Now we could use an Opening to cut the circular hole and then plug it with a seperate Fire Collar Object, but then each penetration has two elements to maintain and accross a large project this can get out of control.

We could also create a Fire Collar Object and then use solid element operations to cut the hole, but that adds up to a lot of subtraction operations slowing everything down.

If we use an Opening tool to cut the hole and at the same time represent the fire collar in the hole we face a limitiation with the Opening tool in that the 2D representation cannot go outside the dimensions of the hole created and so additional thicknesses and clearances cannot be shown.

Any thoughts on how to do this with one object?

Operating system used: Windows

Re: Openings, Penetrations and Fire Collars

CosminF — Wed, 15 Oct 2025 15:55:27 GMT

Hi,

I can share my take on the matter, but I am pretty sure this is not the recommended way to do it - although it has worked fine for me so far:

- for slab penetrations - usually our slabs come in IFC from our structural engineers and they already have their openings and the concrete slabs element are imported as objects (so the hole has a fixed position, I can't move it in archicad). The fire dampers or sealing solutions are represented schematically (i.e. an object/ slab).
- for wall penetrations - for a gland plate for example, I have modeled it out of a curtain wall and classified it as such. The cable tray stops before it and it continues afterwards:
This way I can easily adjust and/or schedule them. This has the drawback of needing a opening in the wall. But you can always use a regular window object with a custom panel for those in a similar manner, but you would be having a harder time making non-rectangular shapes if needed.

And this is quite close to how they will actually be built on-site:

Hope this helps.

Re: Openings, Penetrations and Fire Collars

Barry Kelly — Wed, 15 Oct 2025 07:43:52 GMT

Could you create a fire collar window object?

It would basically be just a solid slab of your fireproof material.

Just model a slab and save as a custom window object.

As a window it will show in plan and 3D.

If you don't add a frame, it will be stretchy.

If you do add a frame, you will need to create one for each size as the frame width will stretch if you change size.

Or you would have to script a purpose made window object if you want it stretchy with a frame.

It won't have holes for each service penetration, but I am not sure that would matter, it would depend on how fussy you want to be.

You can SEO the service passing through, but it has to be to the wall and not the window.

Barry.

Re: Openings, Penetrations and Fire Collars

Matthew Johnson — Wed, 15 Oct 2025 23:37:19 GMT

Barry, agree with the logic of the approach for walls, but what we are trying to do is a single approach for walls and slabs. The only tool that works on both is the Opening tool.