| Scope | Typical range | Notes |
|---|---|---|
| 2-piece powder room (rough-in exists) | $10–14K | Toilet, vanity, tile floor |
| 3-piece with tiled shower | $18–28K | The standard basement build |
| Breaking concrete for new drains | +$3–6K | When no rough-in exists |
| Sewage ejector (below sewer line) | +$2–4K | Pump and pit when gravity cannot drain |
| Spa-grade upgrade (stone, glass, niche) | +$8–15K | Matches our bathroom portfolio |
A basement bathroom lives in the most moisture-exposed room of the house. We build them waterproof-first: membrane systems behind every tiled surface, moisture-resistant board instead of standard drywall, and mechanical ventilation sized for a below-grade room. It is the difference between a bathroom that looks good on handover day and one that still looks good in year ten, which is why every Desire Basements bathroom carries the same lifetime warranty as the rest of the build.
New plumbing and electrical below grade require permits and staged inspections in every GTA municipality. The plumbing rough-in is inspected before the slab is closed, and electrical work is ESA-inspected. If a contractor suggests skipping permits on a basement bathroom, that quote is cheaper for a reason. Our free quote checklist shows what else should be itemized before you sign anything.
The median completed basement renovation in our 2026 Cost Report is $103,000, and nearly every project at that level includes a bathroom. In a legal basement apartment it is required in practice, and it is a large part of why GTA suites rent for $1,700–$2,400 per month. To price your whole project, try the basement cost calculator, and monthly-payment financing is available on every build.
Yes. New plumbing and electrical below grade require permits and inspections in every GTA municipality, with the rough-in inspected before the floor is closed.
Yes. The concrete floor is cut to run new drains, or a sewage ejector handles fixtures that sit below the sewer line. Both are routine parts of a full renovation.
For legal suites it is effectively required, and in family basements it is consistently the most-used upgrade we build. It also supports resale value more than any other single basement feature.
