Estimating
Sources and quantities
How estimate quantities and rates keep a source — layout, takeoff, quote, library, or override — so a later review can see where the number came from.
Updated 2026-08-23
An estimate line is only as defensible as its source. Infrenta keeps quantity and rate sources visible so a reviewer can tell a measured layout count from a placeholder, and a supplier quote from a remembered unit rate.
Quantity sources
Quantities may come from:
- Solar Layout Studio or other layout / BOM outputs
- takeoff
- direct user entry
- a formula that depends on other items
When a layout revision is the source, re-compile from that revision rather than hand-editing a few lines that “probably changed.” See Layout quantities and Connected project record.
Rate sources
Rates may come from:
- a supplier quotation
- a resource or rate library
- a compiled build-up
- an explicit override
Explain This Number should show which of those applied. An override that looks like a method output is how reviews fail.
Allowances and incomplete sources
Allowances and plugs are conscious incompletes. They should remain labeled as allowances. Do not convert an allowance into a measured cost just to make the estimate look finished.
Why this matters on repeated work
C&I and utility teams reuse rate logic across jobs. Reuse is useful only if the quantity identity and the rate source stay attached. Copying last week’s workbook without those sources creates another disconnected version.