Schedule - Wall Material calculate problem (for Wall Layer)

[Anonymous]

Good morning,

As an office witch has the Autodesk Subscription, we’d like to rapport some problems we are facing with Revit, related to the extraction of wall quantities based on Material Take off command.

We need to extract the following materials:

1. Core - Brick (m²)
2. Finishing – Interior (m²)
3. Finishing – Exterior (m²)

We also model the Structure. When we apply Join to calculate the core area (bricks) face without the Structure (keeping the finishing) , Revit doesn’t subtract  (the amount the column take place) the brick and calculates the area as if doesn’t have the Structure.

Trying to find other options, we also tested the command Create Parts, and in this way, Revit makes the right count. However, in this way, Revit doesn’t generates database to be read in Access, with ODBC export.

We would like to know if this is a Revit Error and why the Join doesn’t make Revit disregards the core area on the intersection with the Structure.

For additional information, please check attached file.

Thanks for your attention.

EA+ Architecture Team, Brazil.

[chrisplyler]

Please verify that the column has indeed been joined to the wall.

Without the join, the wall continues through the column even though it isn't visible, as shown below:

Once they are joined, the wall should appear to stop on either side of the column, even though it is a single, continuous element, as shown below:

Please note that the scheduled area and volumn of masonry units has changed from one picture to the next. Also verify that your column is aligned to or otherwise definitely cuts the face of the brick layer. If the either face of the brick layer remains after the join, the area calculation will still reflect a continuous, unbroken wall.

[chrisplyler]

Deleted: duplicate post

[chrisplyler]

Please forgive me. I now realize that - with additional wall layers - I too get the problem you describe. The only way I can get accurate core area take-off is if the column completely breaks all layers.

So hopefully somebody with a better understanding than I have will join the discussion.

[loboarch]

The discrepancy you are seeing between the volumes reported as parts and the volumes reported as a wall is related to the way Revit calculates volumes of walls when joined.  The issue is mostly related to the way walls join to other walls but in this case the issue is a wall joining to a column.  The issue has been logged for consideration to change the behavior in a future release of Revit.

When working with walls using parts will be the way to get the most accurate material takeoff. 

[mitiaburdin]

Hello. Version 2021 has already been released, but this error has not been fixed. How many more decades do we have to wait for this fix? The roadmap included the update: "wall: layers". Does this update relate to this issue?

[loboarch]

---

@mitiaburdin wrote:

Hello. Version 2021 has already been released, but this error has not been fixed. How many more decades do we have to wait for this fix? The roadmap included the update: "wall: layers". Does this update relate to this issue?

---

Solution to the problem is still the same. Parts must be used in these kinds of situations, or understand there are going to be these kinds of small discrepancies on material takeoffs for walls throughout the model and account for it with a factor in your schedule. 

[mitiaburdin]

Give an example of the errors you are talking about. Do I understand correctly that to calculate the area of materials after building the entire model, I must split it into parts? Still, what did the update mean in the roadmap?

 

[loboarch]

Yes parts will give you a more accurate material takeoff. You will have to decide if the added effort of parting out every wall is a reasonable investment of your time, or if being relatively close (+/- 3% - 4%) is "good enough".  

The "Wall Layers" work listed in the roadmap was more related to the ability to create elliptical walls in 2020 and slanted walls in 2021. 

[mitiaburdin]

Thank you for your answer. I think this decision will take some getting used to.