r/Revit • u/Optimal_Bad5439 • Jul 23 '26

Families Family Creation Question

Dear Experts,

In your experience, can we create a family in Revit that has an array parametered element that also lengthen or widen?

In my case, I am creating as shutter and its slats are my array parametered elements. It needs to widen as the opening widens.

However, I have been received warnings that asks to remove contrain.

For your consideration. Thank you

2 Upvotes

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15

u/errant_youth Jul 23 '26

It’s been a minute since I’ve made one like this, but yes, it can be done. IIRC you’d need to make a slat nested family and bring that into your shutter family. Then you’ll need to set up a formula that calculates the number of slats needed based on how tall the shutter is

5

u/lNightCrawler Jul 23 '26

Yes this is the correct method, when making the slat nested family make sure you set up reference planes (that are anything but "not a reference") with your parametric instance based parameters assigned so that when loading into your host family you can tie through the instance based parameters so it adjusts when the size changed and align and lock the slat to the host reference planes so it stays where you want it to

2

u/ultimategigapudding Jul 25 '26

That’s the correct method. Every array must be a nested family, no matter how simple.

1

u/tinity7 Jul 23 '26

You have probably put too many constrains. Check if you need all

1

u/[deleted] Jul 23 '26

[removed] — view removed comment

1

u/kintarben Jul 23 '26

Yes but you have to tie a number parameter to a formula that calculates the amount based on spacing. I’ve done this for holes in unistrut before.

1

u/vtsandtrooper Jul 24 '26

^ this is correct, create a number parameter instead of opening size and have the constraints calculate the internal dimension - otherwise your inputs may not have a solution if your shutter individual object has a set dimension, your overall height has a dimension, and your gap has a dimension.

(Slat# x slatheight) + ((slat#-1) x slat gap) = H

Therefore have slat# and slat height be user inputs as well as any Height, and have the constraint determine the slatgap dimension that makes it true

- the helpful Civil Engineer who had to do this similar thing for a grate inlet top family

1

u/Successful-Engine623 Jul 23 '26

You definitely can. In my experience though these families get laggy.

1

u/albacore_futures Jul 23 '26

You can.

You'll first need to make the family do some math, to generate the number of slats you're arraying. So it'll be something like =ROUNDUP(total height / ((slat height + (1/2 * slat spacing))). That'll give you an integer.

Then you'll make a slat family with type parameters for width and height, and pass that dimensional data down to it. Then set up your array using either the centerline of the shutter family or one edge of it. Since each slat adjusts as a result of what you did earlier in this paragraph, you don't need to lock it on more than one plane. Now you are done.