Estimating Guide
By Phazahn Odom | Founder of Phixmo | Former bookkeeper for residential GCs | Former NFL tight end, Pittsburgh Steelers
Bathrooms are small spaces with big estimating risk. The square footage is tiny but the cost per square foot is among the highest in residential construction. Plumbing, electrical, tile, waterproofing, fixtures, all packed into 40 to 100 square feet. One missed line item or one surprise behind the wall can wipe out the margin on the whole job.
After years of doing the books for residential GCs, here's how to build a bathroom remodel estimate that covers everything and protects your profit.
A complete bathroom estimate covers eight categories. Miss one and you eat the cost.
Removing the existing tile, fixtures, vanity, and flooring. Bathrooms often hide water damage that only appears during demo. Budget for disposal and a dumpster.
This is the big one for bathrooms. Relocating or replacing supply and drain lines, setting the toilet, shower valve, tub or shower drain, and sink. If you are moving fixtures, costs climb, more still if relocating fixtures or working on a slab.
GFCI outlets, lighting, exhaust fan, and any heated floor wiring. Code requires GFCI protection near water.
The category most contractors underestimate. Proper waterproofing behind tile (membrane, backer board, sealing) is what prevents callbacks and water damage. Cutting corners here causes failures.
Floor tile, shower or tub surround tile, and the labor to install it. Tile labor is skilled and time-consuming, especially with patterns, niches, and curbless showers. The range depends on tile choice and complexity.
Toilet, vanity, sink, faucet, shower system, tub, mirror, towel bars, and hardware. The spread is huge: a builder-grade package might be $1,500 while a high-end package exceeds $8,000.
Paint, trim, accessories, and any built-ins. Often underestimated because each item feels small.
GC markup (12 to 18%), permit fees ($300 to $1,500), and contingency (10% recommended for bathrooms because of the high chance of hidden water damage).
These are the line items that consistently get missed and come out of margin.
Underestimating the substrate and waterproofing work leads to either callbacks (if you cut corners) or eaten margin (if you do it right but did not bid it). Budget for proper membrane, backer board, and sealing.
Bathrooms are the most common place to find rot, mold, and damaged subfloor during demo. If you did not include contingency, every surprise comes from your profit. Budget 10% contingency minimum.
Code often requires proper ventilation. If the existing fan is inadequate or the ducting needs work, that is a line item people forget.
Shower niches, benches, and curbless entries take extra labor and waterproofing. If the homeowner wants these, they're not free.
Moving a toilet or shower drain on a slab foundation means cutting concrete, which is expensive. If the plans call for relocation, price it carefully.
Bathroom remodels usually require permits, especially when plumbing or electrical is involved. Check your jurisdiction.
Bathrooms are labor-intensive for their size. Here's a framework.
Demo (8 to 16 hours), plumbing rough and set (varies, often subbed), electrical (8 to 16 hours, often subbed), waterproofing and substrate (8 to 16 hours), tile installation (16 to 40 hours depending on complexity), fixture installation (8 to 16 hours), finishing and punch (8 to 16 hours).
A simple subway tile surround is one thing. A herringbone floor with a curbless shower, a niche, and a bench is a completely different labor number. Price tile labor based on the actual complexity, not a flat rate.
A skilled tile setter in a high-cost market runs $50 to $70/hour. In a lower-cost market, $30 to $45/hour. National averages will burn you.
Setup, cleanup, waiting for materials, and the tight-quarters reality of working in a small bathroom where only one or two people can work at once.
Two ways that save real time.
Describe the bathroom: "60 square foot full bathroom remodel in [city], new tile shower with niche, new vanity and toilet, heated floor, keep the existing layout." Get a categorized estimate in seconds covering all eight categories above, priced from your own completed jobs once you have history in Phixmo, with regional rates filling the gaps. Refine from there.
If you have plans, upload the PDF, calibrate the scale in 2 clicks, and the AI extracts the bathroom dimensions, fixture count, and tile areas, each badged with how it was derived. Generate an estimate from the measurements.
Neither replaces your judgment about waterproofing complexity or the likelihood of hidden damage. They give you a complete, organized starting point so you're refining instead of building from scratch. See how the AI takeoff works, and the same approach for a kitchen remodel.
A sample mid-range full bathroom remodel (60 sq ft) in a mid-cost market. Use it as a sanity check against your own bid, not a substitute for one.
Demolition + disposal
Low
$1,000
Mid
$1,800
High
$2,500
Plumbing
Low
$1,500
Mid
$3,000
High
$5,000
Electrical
Low
$800
Mid
$1,500
High
$2,500
Waterproofing + substrate
Low
$800
Mid
$1,400
High
$2,000
Tile + flooring
Low
$2,500
Mid
$5,000
High
$8,000
Fixtures + fittings
Low
$2,000
Mid
$4,500
High
$8,000
Finishes
Low
$800
Mid
$1,400
High
$2,000
Permits
Low
$300
Mid
$800
High
$1,500
GC overhead + profit (15%)
Low
$1,500
Mid
$2,900
High
$4,700
Contingency (10%)
Low
$1,150
Mid
$2,200
High
$3,600
Total estimate
Low
$12,350
Mid
$24,500
High
$39,800
Based on 2026 mid-cost market rates. Your actual numbers depend on your market, tile complexity, and fixture selections.
Phixmo turns a bathroom scope into an estimate in minutes with AI takeoffs and text estimation, then tracks estimated versus actual on every category so the margin you bid is the margin you keep. The change order workflow and job costing are built for it. Field workers are always free.
Bathrooms pack the most expensive trades (plumbing, electrical, tile, waterproofing) into the smallest space. The cost per square foot is among the highest in residential construction because of this density of skilled work.
At least 10% for bathrooms. They're the most likely place to find hidden water damage, rot, and outdated plumbing during demo. The contingency covers those surprises so they don't eat your profit.
Most residential GCs sub these to licensed trades. Include the sub costs in your estimate and mark them up appropriately. Track them in your job costing against the budget.
Either include a fixture allowance (a budget the homeowner selects within) or have the homeowner purchase fixtures separately and include only installation labor. Make it clear in the estimate which approach you're using.
Include proper contingency, document every change order, bid the waterproofing work accurately, and track estimated vs actual costs as the job runs. Phixmo's job costing and change order workflow are built for exactly this.