As far as I can see that object has fixed sizes and no option for custom sizes.
It may be possible to edit the GDL if you can understand it.
Otherwise it would be a matter of finding a 3rd party object that is customisable (or the exact size you want) - sorry I am not aware of any.
Or you could place a beam for each length you require.
Convert it into a morph and the edit it to the required height.
Save back as an object and then place where you need them.
You will need to do this for each length as they will not be adjustable when you save them back as an object.
Or similarly, create you own joist from slabs laying on the floor (it is easier to create them laying on their side).
Then save as an object with the correct top view.
Again you will need to do this for each length as they will not really be adjustable.
Small length adjustments may be OK as the object will stretch uniformly, but larger ones will not increase/decrease the number of webs.
Or if you don't need them for 3D then just place a normal beam and in sections add 2D lines and fills to represent the joist.
This way you can still schedule the joist if you need to.
If you don't need to schedule them and you don't need to see them in 3D then there is really no need to place them at all.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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