How do you separate measured and provisional scope?
Create separate estimate lines for quantities measured from issued information and quantities introduced to cover an unresolved design input. Use the project definition of allowance; the worksheet does not override contractual wording.
The GAO Cost Estimating and Assessment Guide, published in March 2020, includes a technical baseline, ground rules and assumptions, data, documentation and updating among its estimating practices. This original register applies those documentation ideas to electrical package quantities; it is not a required GAO form.
Sources: US Government Accountability Office: Cost Estimating and Assessment Guide, March 2020
Which columns prevent a hidden scope assumption?
Define what one unit contains before entering a number. For example, a circuit count does not by itself define cable length, terminations, containment or testing. Give those items their own scope treatment where appropriate.
| Field | Entry needed | Why it matters |
|---|---|---|
| Estimate line and unit | Unique line ID; circuit, item or length | Avoid changing the unit during comparison |
| Boundary | Included equipment, work and interfaces | Prevent overlap with another allowance |
| Baseline | Quantity and issued source revision | Distinguish measurement from editorial assumption |
| Provisional input | Quantity, rationale and owner | Expose what remains unconfirmed |
| Related scope | Containment, terminations and testing treatment | Avoid silently extending the line |
| Replacement trigger | Drawing, schedule or clarification needed | Identify what will supersede the assumption |
| Change record | Old quantity, new quantity and approval | Retain the estimate history |
How does the quantity reconciliation work?
Illustrative example. An electrical estimator has measured 18 fictional final circuits from a controlled schedule and included a separate allowance for 6 unresolved circuits. The working quantity is 24 circuits. A later approved schedule confirms 22 circuits within the same boundary. The reconciliation replaces the combined provisional position with 22, a reduction of 2 circuits.
Do not add the 22 confirmed circuits on top of the earlier 24. Retire or replace the provisional lines according to the estimate workflow and retain the reason. If the later schedule also changes the boundary, reconcile that scope change separately before comparing quantities.
This example supplies no market rate. Any cost change requires the project-approved rate basis and the actual associated scope. A difference in circuit count cannot establish a total package saving without those inputs.
What should be checked before bid approval?
Review whether each provisional quantity has an owner, a source status and a clear boundary. Check the estimate summary against the detailed register so a renamed allowance has not been counted twice.
Keep technical assumptions distinct from commercial qualifications. Send any proposed bid qualification through the authorized bid review process. This guide is not legal advice. Engineering design and sign-off remain with the registered engineer on the job.
After an addendum, record both the quantity change and any unchanged assumptions. Closing one design gap does not confirm every other provisional input in the electrical package.
Common questions
What else should the bid team know?
Is a provisional quantity a contingency?
Not automatically. Use the project definitions and record the intended treatment separately.
Can an allowance be deleted after a new drawing arrives?
Reconcile its boundary and quantity against the new information, obtain the required approval and preserve the history.
Does this worksheet provide electrical unit rates?
No. Rates must come from an authorized, project-relevant source.
Primary sources
- Cost Estimating and Assessment Guide, March 2020US Government Accountability Office