Model existing grid ceiling with grid broken up by 4" linear fixtures

[HVAC-Novice]

For a lighting project the existing ceilings consist of 2x2 and 4x4 grids. They have linear 4" wide fixtures installed. But instead of cutting off 4" from one tile, they created a 4" gap for the linear fixture and filled that with the fixture (and a blank to fill the gap to the wall). See picture below. So, each tile on both sides of the fixture still is a full tile. 

with regular ceiling tool there isn't an option to add those 4" strips. My other options are to create separate ceilings or to sue something like a curtain wall.... 

on a previous project they had one half-tile offset in a room and I just used 2 ceilings. Here a long hallway and many rooms have multiple of these " gaps".

Is there an easier or simpler way to model that? Or is multiple ceilings what I have to do? 

Edit: I created walls that are as wide as the gap (actually 3.75" based on submittals). I placed them where the fixtures are and to have the base for the wall be the same height as the ceiling. The distance is 8' between them (8' 3 3/4" o.c.)Then I auto-placed 4x4 ceilings in between the " walls". Then I placed the fixtures on the walls. At least now the ceiling looks like in real life. I'm just not sure this is the best way... 

[ToanDN]

You could split the ceiling, paint the same material and re-align the model pattern.

Or use two ceilings and join them.

[HVAC-Novice]

That works, but is a bit hard to get the exact distances correct. Maybe in a room with with just one of these strips this is fine. I found one ceiling should align with one side of the fixture, and the other ceiling includes the fixtures (so the split is one one side of the fixture) works best to not show a grid piece in the middle of the blank section. 

In a room with 4 of them maybe my wall-method works better since I can space the walls exactly and then create the ceiling. 

I'll do some rooms with either method and see what works best. 

[Lachlan-JWP · Accepted solution]

You can use pyRevit to create custom model patterns. Have a look in this project, I made something similar to what you want. Then you can create the ceiling in as many pieces as you want and align the pattern to suit.

[HVAC-Novice · Accepted solution]

Thanks for sharing this. Unfortunately our IT doesn't let us install unapproved software. But this gave me the opportunity to learn....

I looked at your pat file and this pat-tutorial.

it took me some trials, but here is the pattern code:

90, 48, 0, 0, 100, 0, 0
90, 96, 0, 0, 100, 0, 0
90, 100, 0, 0, 100, 0, 0
180, 0, 0, 0, 48, 0, 0

and it looks like this (measured to double-check):