With custom profiles would be an easy solution. Do a custom profile by drawing it with appropriate fills. These fills are each attached with a construction material. Save the profile with a name. Open beam tool, make it to use a custom profile you just made and draw a beam you had saved earlier.
You can mix profiles to achieve a net, for example. Just use another different profile, and draw it perpendicular to the previous one.
You can then later slice your beam(s) with Solid Element Operations (=SEO or =Boolean operator in some countries) if you need to. Just be aware of their priorities. Keep a higher priority with the cutting element, or it might not cut other elements.
I took a round part apart to demonstrate the stucture.
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