Slab and Footing issue

I am having a couple of different issues.

Firstly I am pouring a slab on footing detail. So the footings will be poured separately to the slab. Based on this I want to quantify the volume separately. So I have drawn the footing as part of the wall system. When I do a takeoff and click the show in model. It shows the slab but not the footings specifically not the footing that the report has been done on? Secondly if I do a report on the model I can identify the difference between the slab and the footings in the takeoff?

the second issue is. Generally, the slab will have a thickening around the edge as part of the connection to the footing. This is easily sorted treating the thickening as a footing function. However, if I want this thickening to change in depth at different points on the perimeter whenever I add a custom footing it breaks the manifold and I cant quantify the slab. Any help would be appreciated

Hi TruLine,

Thank you for your questions. This has been forwarded to our team for review.
If you could provide a few more info below, - that would be great.
PlusSpec License:
PlusSpec Version:
SketchUp Version:
Computer (PC/Mac):
OS Version:

PlusSpec License:
PlusSpec Version: V24.2.0
SketchUp Version: 23.1.329
Computer (PC/Mac): PC
OS Version: Windows 11 Pro



Hi TruLine,

The issue where the footings drawn with the walls aren’t appearing when clicking on “show in model” has been passed onto the dev team. This should be fixed in the next updated. In the meantime, if you draw the footing separately using the Footing Tool they will appear when using this feature.

Currently the takeoff will separate the items into instances which will report each different instance (see image below). Alternatively, if you use assign the geometry to different levels (using the :levels_layers_tool: Levels & Layers Tool) they will also separately within the takeoff & also in the takeoff exports.

Separated Concrete Report

The way I’d recommend adding the thickening would be to consider it like a footing but smaller (like what you’re currently doing) & then going into the group & manually edit the geometry to the desired depth using SketchUp tools. When doing this ensure that the Volume field (highlighted in below image) is appearing where the slab material is applied (circled in below image), otherwise the slab won’t be manifold & won’t estimate. Please note that any manual edit will be reverted if the geometry is edited again using a PlusSpec Tool.

Tip: If you use SketchUp’s “hide rest of model” feature you can just view what you’re looking at when inside of a component or group making it easier to edit. To set this up go to Window > Preferences, select Shortcuts from the menu on the left, search ‘hide rest of model’ in the Filter field, select the function from the list, click into the Add Shortcut field, press the key(s) for the shortcut (e.g. Ctrl + H) & then press the + button. Pressing the key(s) will toggle the feature on/off.

It would be good to see an engineer’s cross-section detail and/or footing layout so I can be certain that I am answering 100% correctly. if you have one, can you upload a screenshot? or even better create a Sketchup model and upload it?

To separate the materials, you could use the Footing tool :footing_tool: and create a material so that the BOQ combines and quantifies different materials EG Name the footing material “Footing 25MPA”
GIF Separating concrete footing material quantities from the main concrete slab in the estimate BOQ in PlusSpecs PlusDesignBuild BIM for Sketchup

What Grant says is correct, yet another way r is to draw the “Special footing detail” inside Sketchup and use the customer estimation tool :custom_estimation_tool:
I made a quick video on the RubySketch Facebook channel [You can quantify anything with the custom estimation tool inside PlusDesignBuild for Sketchup. The key to being profitable in construction is accuracy when quoting and peace of mind that your price is right. PlusDesignBuild enables you to see what you are quantifying, associate material price, supplier details, and auxiliary items like rebar with 100% accuracy. | RubySketch](https://Video: how to estimate custom concrete footings )

The wall Tag is being turned off, and all other concrete is being shown as our thought process was that the footing is a part of a wall, yet in this instance I agree. FYI if you want to see the footing go to tags and click on 1 Floor Tag group and then click on WALL_FOOTING_GROUP. And in the “walls” Tag click Wall_Group Structural. NOTE you can save a scene to automate this if you choose. However, @Grant and I will update this in the next release.

I always ensure that Entity info is open and check the cubic measure before proceeding with a Bill of Quantities.