BILT

BILT
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Monday, 10 February 2014

Revit Multistorey Railings - Story 1


[Edit: Revit 2018 has a new method for creating multistorey stairs & railings, so the issues described here will not be relevant once you upgrade to v2018;  if you are using v2017 or earlier, read on]

Here is a curious story to tell:  This is a description of how to manage railings on a multistorey stair that has been created using the "Multistory Top Level" stair property in Revit (Method 1 in my previous post), and where you have incorporated intermediate landings on each building level of the stair.  The resulting railing will be a single closed loop - both inside and outside joined together. 

The description below assumes that you followed the steps in the previous blog post  to get to this stage.  If your multistorey stair does not include landings at the storey levels (maybe you used floor slabs instead), none of this applies.

Edit Railing
If you try to edit the railing to get rid of the section running across the landing/run junction or the outside edge of the landing, you will run into problems in Railing edit mode

After you delete the unwanted lines and then finish the sketch it will give an error message – it requires a single continuous chain of sketch lines, not a loop within a loop (even if you remove all overlapping lines)


To solve this the railing needs to be first separated into two parts. This can be done by two different methods:
1.  You could duplicate the single railing and then edit each one separately, stripping them back to an inner and an outer railing (Process not described here).
2.  Alternatively, take a few steps back in the stair creation process, to edit the railings before you delete the temporary top flight:

  • Edit the outside railing (because of the top run there are two separate railings). 
  • Delete the segment associated with the extra run

  • Make sure there is a break in the loop by dragging the end of the landing rail line away from the first run line; the gap must be at least 32mm otherwise the lines will automatically rejoin! (That is about 1 ¼ inches in that quaint imperial system used in the USA).

  • NB. If you want the sloping section of rail to extend one tread beyond the lowest riser (common practise), then you need to extend that line by one tread depth before making the 32mm gap.  It may give you a slope warning, but it is not clear why because the railing will be parallel to the flight
  • One method to stop that warning is to make the sketch line overrun dimension just short of a tread depth – by 1mm say (for a 250mm tread, the railing sketch line should extend 249mm past the lowest riser)
  • Then you need to do something similar for the inside loop railing – delete unwanted segments and make a gap. You might again want to extend the sloping rail line by one tread (minus 1mm), and then make the gap in the short landing line

  • Another alternative is to extend the short landing line by at least 32mm, and leave a gap of 1mm to avoid the sloping railing warning. The best option depends on how your rail is defined relative to the sketch line location and how you want the join to work
  • Finish the railing sketch

  • Edit the stair to delete the top flight – the railings should now be separate. NB. This process does break the automatic nature of the railing sketch – it will no longer update when the stair changes

Once you make the stair multistorey again, the railings should behave better. The small gaps may not be perfect but they are a whole lot better than the junctions that Revit makes normally

If you don’t want the railings to run across the back of the stair landings (eg. doors onto landing), you can edit the railing to remove segments but you'll lose the side railing of the landing (because you need a continuous chain of sketch lines in the railing)

Then you need to add a new railing to the landing sides: host it on the stair if you want it to be the same on both levels (it will become multistorey if the stair is); or host it by level if you want different railings on each landing
 

Watch out for the “Tread/Stringer Offset property for the railing so that it will align properly with the other railings (defaults are different for automatic railings and manually created railings)

Non-multistorey railings must be hosted by level, not on the stair – that way they can be different on each level

However, if you find all this is too fiddly, or else you need the top landing to be different then you may need to try Method 2 for multistorey stairs.
You could also lobby Autodesk to fix the railing tool so that it works better with the new stair by component tool!  Maybe one day we won't have to invent these horrible clunky workarounds.

1 comment:

  1. Nice tutorial, I wondering if there is a way to a balustrade with glass panels ? I can do the glass panels but they don't finish properly at the beginning and ends as the panel continues and does get trimed.

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