Project parameter on materials in schedule

[Jessicas]

Hi All,

I've got a number of schedules created and once I got the hang of how revit likes this its gone pretty good.

I've got a material take off schedule (see attachment) to which i've added a project parameter called Waste Factor. Now most of the time adding a value in this column works great. enter a value for the material its added to the # of units and life is good.... EXCEPT sometimes when you add a value in one Waste factor blank it adds it in a few other blanks... this doesnt work very good when different types of materials require different waste factors....

Anyone have any ideas why entering a value in one blank sometimes adds the same value to another spot? See attached images. In the 4th section under doors, i added 1.05 to the second waste factor blank under the Jambs material and it added the same value to the Gypsum Corner Bead and the Door stop materials.

This also happens if I add a value to the Gypsum Board - Standard 1/2" x 54" x 12' material under walls the same value is added to the "Paint - Dulux Diamond Matte" material...

Thanks in advance.

[Sahay_R]

Instead of adding Waste Factor as a Project Parameter, why not add it in as a Shared Parameter? That should prevent things like this from happening.

[Jessicas]

How do i edit the Waste Factor shared parameter on a Material? I can't type anything into the spot is there a different spot to enter the value?

I tried using a shared parameter at the begining but was unable to add a typed value in the material take off in the schedule and couldnt find another place to add a value.

---

@rsahayUZMK9 wrote:

Instead of adding Waste Factor as a Project Parameter, why not add it in as a Shared Parameter? That should prevent things like this from happening.

---

[ToanDN]

@Jessicas

It doesn't work because the Waste Factor parameter needs to be by Material, not by Element Type or Instance.  Unfortunately, Material is not a separate Category that you can assign the parameter to so the idea of each material having an unique factor does not fly.

You either need to export the schedule to Excel or use a Dynamo script to get what you need (which I am not be able to help you with).

@Sahay_R

Making it a shared parameters does not make any different.

[ToanDN · Accepted solution]

@Jessicas

I was wrong.  You can do it if the Waste Factor is an instance parameter.

[Jessicas]

@ToanDN that seems to be the exact way I have mine set up but it still randomly changes the values of other materials..I'm not sure why. See screenshots below.

Is it maybe because i have the materials categorized by category? by the type of model they are on? Walls, ceilings, floors ect?

[Jessicas]

Well its not the category filter thats causing the problem because its just as bad without the category option -_-  .... I entered a number in the waste factor column starting with a 1 and ending at 24 and as you can see the numbers are just all over the place... some fields are even blank.

When i made the waste factor parameter it looks like a did a "Check All" when selecting which category I wanted this parameter assigned to (see screenshot) Maybe thats the problem?

[ToanDN · Accepted solution]

You should not assign the Waste Factor parameter to any Categories other than Materials.