The five decisions that move the number
- 1Whether the toilet drain and wet wall stay where they are
- 2Whether the wet area is a tub, an alcove shower, or a large walk-in
- 3Whether the entry is curbed, low-profile or fully curbless
- 4Tile format, material and layout pattern
- 5How much of the electrical, ventilation and framing is being corrected at the same time
Notice that none of these is a brand. Fixture selection has a visible effect on a budget, but it is a linear one — you can spend more or less on a faucet at any point. The five decisions above change how many hours of skilled labour the room needs, which is why they dominate.
Why square footage is a poor predictor
A large Eagle primary bathroom that keeps its layout can cost less than a small North End bathroom that needs a drain moved, a floor levelled and a vent installed. Bathrooms are priced by the density of work, not the area of floor. The fixed items — demolition setup, plumbing, waterproofing, inspections, fixture setting — barely scale with room size at all.
| Category | Scales with room size? | Scales with complexity? |
|---|---|---|
| Demolition and protection | Slightly | Yes — more so in occupied, single-bathroom homes |
| Plumbing and electrical | Barely | Strongly — relocation is the driver |
| Waterproofing | Somewhat | Strongly — benches, niches and curbless entries add detail |
| Tile labour | Yes | Strongly — format, pattern and substrate prep |
| Fixtures and cabinetry | Yes | Selection-driven rather than complexity-driven |
| Permits and inspections | No | Yes — by scope of permitted work |
Hidden conditions, and how to handle them honestly
In homes built before the 1960s — common in central Boise, Caldwell and older Nampa — some conditions cannot be known until demolition. Galvanised supply lines, rotted subfloor under a leaking pan, undersized or absent venting, and previous unpermitted work are the usual four.
- Ask for a scope that names the conditions that would change it, rather than one that pretends none exist
- Ask how a discovered condition is documented and priced before the work is done
- Expect an allowance or a stated exclusion for subfloor repair in an older home, not silence
- Treat a quote produced without seeing the room as an estimate of the contractor's optimism
This guide reflects general construction practice and is educational. It is not a substitute for manufacturer instructions, adopted building codes, or the requirements of your local building authority. Verify anything affecting permits, code compliance or product warranties before relying on it.
Frequently asked questions
Sources and verification
- Tile Council of North America (TCNA) Handbook — installation methods referenced for substrate and waterproofing practice.
- Manufacturer installation instructions for the specific waterproofing, setting and grout products used on each project.
- City of Boise, City of Meridian, City of Nampa and Ada/Canyon County building departments — permit and inspection requirements, verified per project.
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