When the escalator question was put to us a short while ago, we took time to scout around and see what was already available in one form or another. But what we found didn’t really float our collective boat. We certainly saw some very pretty models, make no mistake about it, but they were lacking something… Steps for one, along with the point and click ease which we rely on so often and almost take for granted in the program we all hate to love: Revit.
So we gathered round the table, coffee or tea in hand, depending on national preference, and asked ourselves: What would we want from an escalator family? To which we replied:
- Automatic sizing between levels
Doesn’t seem like too much to ask, right?
Not so fast. Getting a model, one built in a Mechanical Equipment Template, to auto-connect between floors is easier said than done. So we searched for a while, and finally found a template that auto-leveled. We did a few tests, and realized that it could work. There were a few false starts, however, as we discovered that putting any kind of dimension in between the levels completely negated the template’s auto-leveling abilities. So we made the top and bottom landings on their appropriate planes, and had the rising structure of the escalator as a sweep, locked at an angle to the horizontal plane, with the end points of its path locked to the two levels. Worked like a charm.
Next came the introduction of the steps. In previous escalator models, we had access to the vertical distance between levels and the horizontal length of the model as family parameters, which made step numbers and placement a simple application of your old friend Pythagoras’ theorem. Alas, in the all-singing-all-dancing auto-leveler, we didn’t have access to any of the lengths - horizontal, vertical or diagonal. Why not? Because just like with the space between levels, attaching dimensions to any one of the lengths broke the automation.
Again, there was much discussion and drinking of hot beverages.
Then a member of our team had an epiphany: There is one type of family that doesn’t need a length dimension. If you just click and draw a line, the family repeats itself along it ad infinitum. The Generic Line Based Family! This led to some preemptive rejoicing, as we ended up having to re-build and re-nest the Line Based family a number of times to actually get the thing to work.
In our first attempt, we thought we were being clever and seeing problems before they occurred. We said to ourselves, “If the line is going to follow the rising sweep of the escalator, and we build the steps flat… they’ll make a segmented slide, and we don’t want that!” So we built the steps at an angle with the tread of each step 30° from the horizontal, from the path of the Line Based Model. Didn’t work.
Looking back, a little pre-testing should have been done. The steps were indeed at an angle, but in a line stretching horizontally from the base of the escalator backwards, into the distance, and never rising from that plane. Apparently, the Generic Line Based model’s path doesn’t like being hosted on geometry, and without any major planes built between levels, there was nowhere other than lower level plane to draw it.
We needed a quick re-think, again. This time around we found our answer, one that now seems almost obvious. We built the steps rising from the path in the Nested Generic Line based model. “Of Course,” we said, slapping out foreheads at the simple logic of it all. From there, we nested the family’s reference planes in place, and it was all-systems-go. Buy & Download this Revit Escalator Family.