The drag icon will appear if the dimension is controlled by an instance parameter.

Could you clarify about the interruption of the beam?

Hi alexo4141, yup, datbis exactly wat i wanted to do. Wat i mean s, can u give me somehow a procedure on how to model that PT beam? I want that the lengths of the beam can be adjusted depending on the length of the span. For example, in my framing plan, i have a PT beam whose length is 12m. But, the 7m length is 500mm depth, the 3m length is 700mm depth and the remaining 2m is 500mm depth. So i will create a beam base on that family so that the schedule will detect only one beam instead of creating 3beams. But how about if i have another PT beam on the other side whose length is 15m and the depths are on different lengths? What shall i do, or create a parameter in my beam family, so dat my family is intellegent enough to handle dat different beam lengths and sizes situation. I hope it clarify this one. Tnx again.

Alright, just made it on the corner... (RST2012)
I really don't know if it's what you're looking for.

HTH

EDIT: In case you're interested, I also made a post tension beam with blend (which means that the height transition is progressive)

hi alexo4141, tnx for creating a family... this is exactly i wanted.. i have reviewed your family so that i will know how you control some of the parameters. thanks again.