How do I know if there's mold behind my bathroom walls?

Common signs include a persistent musty smell, discoloration or staining on walls near the shower or tub, soft or bubbling drywall, and paint or caulk that keeps failing no matter how often it's redone. Because bathrooms trap moisture behind tile and drywall, mold can be present well before it's visible on the surface.

What actually causes mold to grow behind bathroom walls?

Mold needs moisture, warmth, and something to feed on — conditions bathrooms provide naturally. It usually comes from a leak (plumbing, a shower pan, or a roof), inadequate ventilation, or waterproofing that failed or was never installed properly behind the tile.

Can a roof leak really cause mold inside a bathroom?

Yes. Water doesn't always show up where it enters. A roof leak can travel down through the structure and show up as moisture or mold in a bathroom on a lower floor, well away from the original entry point.

Do you need a permit for a full bathroom renovation in Toronto?

It depends on the scope. Renovations involving new plumbing rough-in, moved fixtures, or electrical work typically require permits and inspections. Straightforward fixture swaps in the same location usually don't. We handle the permit process as part of the project.

How long does a full bathroom renovation take?

A typical full bathroom renovation runs about 2–3 weeks of construction, plus 1–2 weeks for design and 1–2 weeks for ordering accessories and fixtures beforehand. Projects that uncover hidden issues, like mold or leaks, can take longer once that work is added to the scope.

Modern Etobicoke bathroom with dark vanity and white tub

From and Outdated to Modern and Fresh

Etobicoke, Toronto — full bathroom gut renovation with a freestanding tub, new walk-in shower, and the root cause of a hidden mold problem fixed for good.

Full bathroom gut renovation

Mold & roof leak remediation

Freestanding tub install

In-house design & construction

Modern Etobicoke bathroom with black vanity and soaking tub

An outdated bathroom hiding a bigger problem

The existing bathroom was messy, moldy, and worn out — an old alcove tub, a tired walk-in shower well past its life, and a layout that no longer worked for the homeowners. They came to us wanting a full refresh: a new freestanding tub, a rebuilt walk-in shower, and a new vanity.

Once we opened up the walls, we found the real issue: mold had been growing behind the walls, caused by two separate roof leaks letting water travel down into the bathroom area over time. What looked like an outdated bathroom was also a hidden moisture problem that needed to be fixed at the source, not just covered up.

What we found behind the walls

Mold had developed from water tracking down from two roof leaks above the bathroom. Both leaks were repaired and the affected framing and drywall were fully remediated before any new finishes went in.

Modern bathroom in Etobicoke with vanity and toilet.

Modern Etobicoke bathroom with vanity and bathtub

Bathroom renovation in Etobicoke with new drywall and window.

01 Demolition

We gutted the bathroom completely — removing the old tub, shower base, vanity, and all fixtures down to the studs, so we could rebuild everything from zero.

02 Mold & Leak Remediation

With the walls open, we found mold caused by two roof leaks tracking water down into the bathroom. We repaired both leaks at the source and fully removed the affected mold and framing before continuing.

03 Plumbing & Electrical

New plumbing rough-in for the freestanding tub location, the rebuilt walk-in shower, and the new vanity, along with updated electrical for lighting and fixtures.

04 Waterproofing

A full waterproofing membrane was installed throughout the wet areas before tiling — especially important given what we'd just found behind the old walls.

Modern bathroom renovation in Etobicoke under construction

Modern Etobicoke bathroom renovation with vanity and shower.

05 Tile, Fixtures & Accessories

Tile installed through the shower and floor, followed by the freestanding tub, new walk-in shower glass, vanity, and all fixtures and accessories.

06 Paint & Final Walkthrough

Final paint, a full clean, and a walkthrough with the homeowners to confirm every detail before handing back the keys to a bathroom that finally works — and no longer hides a moisture problem.

A beautiful, modern bathroom — and no more hidden mold

The old alcove tub is gone, replaced with a freestanding tub. The worn walk-in shower has been fully rebuilt with new tile and glass. A new vanity completes the space — and just as important, the roof leaks that caused the original mold problem are fixed, with proper waterproofing now protecting the space going forward.

Modern Etobicoke bathroom with black vanity and white tub.

Modern Etobicoke bathroom with glass shower and black vanity

Mold fully remediated

Root cause (roof leaks) repaired, not just covered up

Licensed & permitted

Plumbing and electrical work permitted and inspected

One in-house team

Design, engineering & construction, no subs

$5M insurance & WSIB

Commercial liability + WSIB covered

2-year warranty

Minimum on all completed work

Zero failed inspections

Clean record since founding

Bathroom renovation questions

Noticing stains in your bathroom?

We'll assess what's really going on behind the walls, fix it at the source, and handle the whole renovation in-house — from remediation to final walkthrough.