How it works
The main line item Qty field works well when all materials share the same measurement source. But when different materials depend on different measurements, you can create custom elements and point each material's formula to the correct one.
For example, in a wall repair line item:
Drywall sheets calculate from the line item Qty (square footage)
Screws calculate from a custom element called "Length of Wall" (linear feet)
Each material stays tied to its correct measurement source, so changing one value won't accidentally affect unrelated materials.
Step 1 — Add a custom element
Open the line item, click the three dots next to the total price, and select Edit Mode.
In the Main tab, click + Add Element. In the Create a New Element pop-up:
Type: Value Unit
Name: e.g., Length of Wall
Quantity: e.g., 150
Unit: e.g., Feet
Step 2 — Link the material to the custom element
Go to the Materials tab. Find the material that should use the new element (e.g., Screws).
Click the three dots on the material row and select Set Up Conversion Formula.
Update the formula so it references the custom element (Length of Wall) instead of the main line item Qty. For example, if you need 1 box of screws per 25 linear feet:
Length of Wall (150 ft) ÷ 25 ft per box = 6 boxes
Step 3 — Enable Round Up (optional)
In the formula settings, enable Round Up so the quantity always returns a whole number. For example, 6.3 boxes rounds up to 7.
Step 4 — Save and test
Save the formula. Then test by changing both values independently:
Change the line item Qty (square footage) → drywall sheets should recalculate, screws should stay the same
Change the Length of Wall element → screws should recalculate, drywall sheets should stay the same
Video Overview
Adding a custom field (Length of Wall), updating material formulas to use it, and testing that each material calculates from the correct measurement source.
What Happens Next