Compare the scope, not just the total
The lowest total is not always the lowest cost. One estimate may include the permit, pressure test, drywall patch and trench restoration; another may list only the pipe work and leave the rest to you. Some differences are honest disagreements about the best route or material.
Fill in one column per estimate. Blank cells are questions to ask, not reasons to disqualify anyone.
Side-by-side comparison
| Item | Estimate A | Estimate B | Estimate C |
|---|---|---|---|
| CSLB license number, checked at cslb.ca.gov | |||
| Description of work | |||
| Route of the new or repaired line | |||
| Pipe material(s) and size | |||
| Load calculation includes all appliances? | |||
| Permit included and who pulls it | |||
| Pressure test included | |||
| Valves and connectors included | |||
| Trenching or wall access included | |||
| Patching and restoration included | |||
| Who restores gas and relights pilots | |||
| Exclusions listed | |||
| Total and payment schedule |
Common reasons estimates differ
- Different routes: attic versus wall, or around versus under a patio
- Different pipe sizes based on different load assumptions
- One includes upsizing the trunk, another taps an existing branch
- Permit and inspection included or not
- Restoration of drywall, stucco, concrete or landscaping included or not
- Replacing old valves and connectors while the system is open
Making the comparison fair
- Give everyone the same information.Share the same appliance list and planning worksheet with each plumber.
- Fill in the table.Copy each estimate's details into its column and highlight blanks.
- Ask about the blanks.Contact each plumber to fill in missing items, such as whether a pressure test is included.
- Ask about different approaches.If routes or pipe sizes differ, ask each plumber why they chose theirs.
- Decide on full scope.Compare totals only after every column describes a complete, permitted, tested job.
Follow-up questions to send
- Does your price include the permit and inspection?
- Will you pressure test the new piping before gas is restored?
- What pipe size did you choose, and what load did you assume?
- What surfaces will you restore, and to what level?
Common questions
Is it rude to ask plumbers to explain differences?
No. Professional contractors expect questions about their approach, especially for gas work.
What if one plumber recommends a bigger job?
Ask why. Sometimes a larger line or extra valve replacement is justified by the load or condition of the system.
Should I share one estimate with another plumber?
You can share your scope and questions without sharing prices, which keeps the comparison about the work.
General information for Villa Park, not a quote or professional advice. In an emergency, call 911.