PDA

View Full Version : Can you add a parameter to a material to aid in costings?



robinhill833400
2012-05-20, 10:19 AM
Using Revit 2013:
In the material editor in the first drop down box with the material name there is box where you can enter the material cost, and you can access this from a Multi-Category Material Takeoff Schedule, and multiply by the Material Area, which works.
This allows walls for example to be costed with a list of materials with amount and total cost.
But Costs change over time, and we usually deal with this using a Tender Index, which updates Quarterly.
So I want to include with the material cost the tender index at the time the cost was established (Inevitably new costs will get added at different times with different tender index values)
Then I would set the Current Tender Index in the project, and in the schedule I could include the formula:
Current Cost = Current Tender Index x material cost / tender index
That would allow me to track changing costs over time and allow for regional variations in tender prices using published price book data without having to amend every material cost.

But:-
How can I add a parameter to the material itself, that can be accessed from a schedule?
It must be possible as there is a button at the bottom of the editor labelled custom parameters, but this doesnt seem to allow any to be added and currently is blank.

Any ideas?

dannysmelcer564090
2012-05-20, 07:48 PM
Not sure how any of it would work but just throwing something out there, under the custom parameter button you have to add a shared parameter to your project/template. Go to Manage>Project Parameter, add a shared parameter, check "materials" under categories, press select etc etc.. Let me know if you discover anything.

david_peterson
2012-05-20, 07:53 PM
In 2013, you can apply all kinds of x-data to materials. You can then apply the material to your families. From that you can extract anything from costs, to R-values in theory.

Alfredo Medina
2012-05-21, 03:36 AM
If you create a new project parameter that applies to Materials, based on a shared parameter named such as "Tender Index", (number), then, the properties dialog box will show "Tender Index" in the Materials dialog box under "Custom parameters". There, you can enter the value. Then, the parameter will show up in the list of available fields of a Material Take-off schedule, as "Material:Tender Index", and then you can include that field in the formula of a new calculated value.

robinhill833400
2012-05-23, 09:30 PM
This is really confusing..
I have created my shared parameters :
Tenderindex ...as ProjectInformation for the current Tender Index
and
atTI ...for the Tender Index at the Time the cost is entered into the database - created as a Type parameter

this works for objects like windows but not materials, as materials does not appear in the Categories list for a TYPE parameter


Yet,
if I create an Instance Project parameter, Materials shows up in the Categories list!
Creating that instance parameter I can then add a value for it in Custom parameters for the material as Alfredo says.
I can then add it to a multi Category take off schedule...but no value appears for it in the schedule!

Is this because its an instance parameter when there is no instance as such? or is there?

Thanks for the input so far.
It seems odd that I need to use a Type parameter for things like windows
and instance for materilas.
and odder still that the values for the instance parameter used with materials dont appear in the schedule.

robinhill833400
2012-05-23, 09:35 PM
even odder...if I add a value to the instance parameter in the schedule, it appears in the custom parameters in the material editor, and I can then go to another material in the material editor and add a value for that under custom parameters which does appear in the schedule.
I guess somehow this forces revit to make the connection, but seems a bit buggy, certainly not intuitive.

jsteinhauer
2012-05-23, 09:59 PM
Robin,

Below is my step-by-step instructions I follow to add a custom Material to objects. There is also a link to a post that taught me how to do this.

1. Under the manage tab, select 'Project Parameters'
2. Select 'Add' button on the upper right of Project Parameters dialog box.
3. On the Parameter Properties dialog box, select 'Shared Parameter' then 'Select'.
4. Browse to your new shared parameter for Tenderindex, and click 'OK'.
5. Back in the Parameter Properties dialog box, select which 'Group' to place this parameter under at the bottom left of the box. On the right there is a list of Categories, scroll down until you find 'Materials' and check the check-box.
6. Click 'OK' to take you back to the Project Parameters dialog box.
7. Repeat steps 2-6 until all required parameters are added to your project.

If this is something that is going to be used a great deal in your office, I would have your BIM Manager add it to your firm's standard template.

http://forums.augi.com/showthread.php?134214-Revit-amp-Life-Cycle-Cost-Analysis

Cheers,
Jeff S.

robinhill833400
2012-05-23, 10:53 PM
Thanks Jeff, I see you've been down this same path already.
I had intended to add it to the template once I know its working robustly.

At the moment I am thinking in terms of material take off and costing for elements like walls,
and then doing it by element for things like windows.

I could however do it by element for walls as well instead of relying on material costs...the issue I've just realised is that
if I bring in a thicker insulation for example, this is not reflected in the material cost, plus costs dont always increase linearly with thickness even if I factored that in (and labour element ceertainly isnt linear in increase... it costs almost as much labour to put in a 65mm batt as a 100mm batt) .
I could of course have different materials and costs for the differnet thicknesses available
eg say
Dritherm Insulation 65mm ...rate £4.00
Dritherm Insulation 85mm ..rate £4.50
Dritherm Insulation 100mm ..rate £5.25
but this could end up with lots of materials to make and cost input


So maybe it might be better to set wall cost etc by element not material? Also the issue of hidden costs like wall ties that wont get pulled in when creating a new wall.
Either way it starts to be more work than expected to use this, albeit it is very tempting to be able to create a budget cost that changes as the scheme develops.

Has any one any practical experience of this, and which way was it implemented..cost by element or cost by material? or a mix? Any other pitfalls?
And what happens with the next Revit release...will the extra parameters added be carried over in any new programme update? I note that my template didnt update this time to pull in the thermal characteristics of materials in the 2013 update and so I had to recreate it using the standard 2013 construction template.

ANy further thoughts people?

LP Design
2012-05-24, 06:45 PM
Navisworks. That's kinda what its for.
-LP