Line-item breakdown
Use these ranges to compare apples-to-apples bids. Percentages shift if you keep the tub and only refinish. Moving a toilet blows the mechanicals share. A tub-to-shower conversion that leaves drains in place is a different mix than a layout change.
- Demo and disposal: 5–10%
- Plumbing and rough-in: 15–25%
- Tile and shower: 20–30%
- Vanity, top, and fixtures: 15–25%
Where costs spike
Curbless showers, radiant heat, and moving the toilet or drain add labor and materials — linear drains, heated floors with a thermostat, and custom glass are the usual extras. Glass is often a different company with a different schedule.
- Linear drains and curbless entries
- Heated floors with thermostat
- Custom glass enclosures
Wet-area labor is the silent majority
Homeowners see the vanity photo and miss the pan, membrane, tile labor, and glass. In a mid-range hall bath those wet lines often rival everything else combined. A breakdown that lumps “tile” without waterproofing is not a breakdown.
- Ask for shower, floor tile, and walls as separate rows if the room is a gut
- The fan, GFCI, and lighting are electrical — they do not hide inside the vanity line
- Waterproofing is not the line to cut when the quote runs high
Build the spreadsheet before you shop tile
Split the sheet into wet area (pan, membrane, tile labor), dry area (vanity, lighting), mechanicals (fan, plumbing, electrical), finishes, and a hidden-condition line (about 15% as a planning placeholder — not a measured national average). Freeze the layout, then shop.
- If the toilet and shower stay put, mechanicals stay smaller
- Glass and tile labor usually move more than the vanity photo you saved
- Write “allowance” next to any fixture you have not actually purchased
How to read three bids without averaging them
Averaging a $12k bid and a $28k bid is not a budget. Line them up by bucket. The cheap bid is often missing membrane, dump fees, or a working fan. The high bid may include a layout change you did not ask for.
- Give every bidder the same drawing and fixture list
- Flag any line that says “as needed” or “allowance TBD”
- Do not release demolition until glass lead times and tile quantities are known
What contingency is for (and what it is not)
Contingency pays for rot, out-of-plumb walls, and a drain that is not where the drawing said. It is not a slush fund for a more expensive vanity you spotted after demo. If you want a better fixture, that is a change order funded from a separate “upgrades” line. Each extra niche in a 35-square-foot room is a change order. Freeze when waterproofing is named, the layout is signed, and contingency is still intact.
- If contingency is gone before tile, stop adding fixtures
- Photograph existing plumbing before demo for the plumber
- Keep a dated change-order log even for “small” extras
Payment timing that keeps you solvent
A large deposit before materials exist is how homeowners lose leverage. Tie draws to named milestones: waterproofing flood-test passed, tile on site, glass measured. Special-order tubs can require a deposit to the supplier, not a blank check to a GC.
- Ask who holds fixture deposits and whether they are refundable if lead times slip
- Do not pay for tile labor before the flood test if the setter uses a membrane system
- Keep retainage (often about 10%) until punch list items — caulk, fan, GFCI — are done