Bathroom Quote Comparison Checklist
A printable 16-point decision worksheet designed to normalize residential bathroom bids. Never compare contractor bottom lines until every underlying specification—from continuous wet-area waterproofing membranes and 24-hour flood tests to dedicated 20A GFCI circuits, exterior exhaust ducting, and municipal trade permits—is verified on an identical scope.
Hi [Contractor], I am requesting an itemized quote for a [5x8 ft (40 sq ft) Bathroom Remodel] based on CSI 22 40 00 specifications: - Wet Area: [Acrylic Tub/Shower Combo] with continuous waterproof membrane (Schluter Kerdi or equivalent) - Shower pan test: 24-hour standing water flood test prior to tile setting - Vanity & fixtures: [36" Single Vanity] with new shut-off valves, P-trap, and toilet reset - Ventilation & electrical: 110 CFM exterior-ducted exhaust fan and dedicated 20A GFCI circuit - Permitting and debris cleanup included Please provide line-item pricing for labor, materials, and disposal.
1. Homeowner Baseline Parameters
2. The 16 Critical Bathroom Specifications
CSI 22 40 00 • 09 30 00 Scope| Scope Specification Item | Industry Standard Target | Bid A | Bid B | Bid C |
|---|---|---|---|---|
| Group A: Wet Area Waterproofing & Tile Substrate | ||||
| 1. Shower/Tub Waterproofing Membrane Continuous sheet membrane vs. liquid paint-on | Schluter Kerdi / Wedi bonded sheet membrane (ANSI A118.10) | □ | □ | □ |
| 2. Shower Pan 24-Hour Flood Test Standing water test prior to tile setting | Plug drain and fill pan with 2" water for 24 hours to prove zero leak | □ | □ | □ |
| 3. Cement Backer Board & Seam Tape Substrate behind shower wall tile | 1/2" Durock/HardieBacker with alkali-resistant fiberglass mesh tape | □ | □ | □ |
| 4. Subfloor Rot Inspection & Unit Rate Pre-priced rotten OSB/plywood replacement | Explicit $/sq ft rate for 3/4" subfloor replacement ($25–$45/sq ft) | □ | □ | □ |
| Group B: Plumbing Rough-in & Fixtures | ||||
| 5. Shower Mixing Valve & Anti-Scald Pressure-balancing valve (ASSE 1016) | All-brass rough-in valve body (Moen, Kohler, Delta) with stops | □ | □ | □ |
| 6. Water Supply Lines & Shut-Off Valves Fixture isolation stops | New 1/4-turn brass ball valves on toilet & vanity supply lines | □ | □ | □ |
| 7. Drain-Waste-Vent (DWV) Modifications PVC/ABS P-trap and stack pitch | All-new schedule 40 PVC trap assembly with cleanout access | □ | □ | □ |
| 8. Toilet Flange & Heavy-Duty Wax Ring Flange secured over finished tile | Flange mounted flush on top of finished tile with solid brass closet bolts | □ | □ | □ |
| Group C: Vanity, Countertop & Flooring | ||||
| 9. Vanity Cabinet Box Construction Plywood vs. particle board | 1/2" to 3/4" solid plywood box with soft-close undermount slides | □ | □ | □ |
| 10. Vanity Countertop & Undermount Sink Fabrication & mechanical clips | Quartz or vitreous china top with epoxy-anchored sink clips | □ | □ | □ |
| 11. Floor Tile Uncoupling Membrane Anti-fracture layer under floor tile | Schluter Ditra uncoupling membrane to prevent floor tile cracking | □ | □ | □ |
| Group D: Electrical, Ventilation & Finishes | ||||
| 12. Dedicated 20A GFCI Circuit (NEC 210) Dedicated countertop receptacle circuit | Dedicated 20-amp, 120V circuit with GFCI outlet within 36" of sink | □ | □ | □ |
| 13. Exhaust Fan CFM & Exterior Ducting Direct outside exhaust (IRC R303.3) | Minimum 80–110 CFM fan ducted through soffit/roof with damper (no attic dumps) | □ | □ | □ |
| 14. Moisture-Resistant Drywall & Paint Non-tiled wall surfaces | Mold-resistant drywall (greenboard) with satin/semi-gloss antimicrobial paint | □ | □ | □ |
| Group E: Site Protection, Permits & Warranties | ||||
| 15. Municipal Plumbing & Electrical Permits Permits filed under contractor license | Trade permits pulled with rough-in and final plumbing/electrical sign-offs | □ | □ | □ |
| 16. Workmanship Warranty & Milestone Cap Written guarantee & deposit terms | Minimum 2-year written warranty; deposit capped at 10–15% max upfront | □ | □ | □ |
3. Interactive Bathroom Bid Normalizer
Enter bottom-line quote amounts and adjust for missing specifications to calculate true apples-to-apples cost.
4. Three Fatal Bathroom Bidding Traps to Avoid
• Pitfall 1: Liquid Membrane Skips
Many cut-rate contractors apply only a single thin coat of liquid paint-on waterproofing over drywall or skip the 24-hour shower pan flood test. If the water barrier has pinhole leaks, moisture silently seeps into the subfloor framing, creating thousands of dollars in rotted structural joist repairs.
• Pitfall 2: Attic Exhaust Dumping
Tying a new 110 CFM exhaust fan into the attic cavity or pointing it toward a ridge vent rather than cutting a direct exterior duct penetration through the roof or soffit violates IRC R303.3 and leads to mold growth on the underside of roof sheathing.
• Pitfall 3: Reused Outdated Wiring
Reusing older 15-amp branch wiring shared with bedrooms causes bathroom breakers to trip whenever high-draw hair dryers (1,875W) are used. Ensure bids specify a dedicated 20-amp GFCI circuit per NEC Article 210.