I have been renovating Ottawa bathrooms since 2005. Over 500 of them. The bathrooms that come back to haunt people are not the ones with the wrong tile choice. They are the ones where someone took a shortcut behind the wall, and nobody saw it until water did.
Here are the four shortcuts I see most often. Three of them happen because a contractor wanted to finish faster. One of them happens because the homeowner asked to save money. All four of them cost more in the end.
1. Skipping the subfloor inspection
You pull a 30-year-old toilet. The flange looks rusty. The wax ring is half melted. The plywood under it is dark and a little soft. The lazy move is to scrape off the wax, drop a new flange, and tile right over it.
The honest move is to cut a 24-inch by 24-inch square out of that subfloor and look at the joists. Nine times out of ten in an older Ottawa home in the Glebe or Hintonburg, that joist has rot on the top inch. Sometimes the rot runs three feet sideways. Sometimes the joist is half its original cross section.
If you tile over a soft subfloor, your grout will crack within 12 months. Within 24 months your tile will pop. Within 36 months you have a structural repair on top of a redo of the bathroom you just paid for.
What a real subfloor check costs
An hour of demo time and a sheet of 3/4-inch plywood. It is a small line item on a fresh build. Catching joist rot at this stage avoids a structural repair down the road that costs many times more than the inspection that would have caught it.
2. Painting over rotted drywall
Mould-stained drywall behind a tub surround is common. Older Ottawa bathrooms with poor venting have it on the ceiling above the shower too. The wrong fix is to wipe it with bleach, prime with stain blocker, and paint.
The right fix is to cut it out, find the source of the moisture, and replace the drywall with mould-resistant board. Bleach kills surface mould. It does nothing to the spores already inside the gypsum. Six months later you see a brown halo bleed back through your fresh paint.
If the rot extends into the framing behind the drywall, that gets cut out too. We have pulled studs in century homes near Sandy Hill that crumbled in the hand. The owner had painted over them three times in five years.
3. Generic vanity install over an uneven floor
Older Ottawa houses settle. A 1955 bungalow in Nepean rarely has a flat bathroom floor. The high spot might be 9 mm above the low spot across a four-foot run. That is a real measurement we took last month in Findlay Creek.
The shortcut is to drop a big-box vanity onto that floor and shim the front feet with cedar shake. The drawers do not close right. The countertop pitches forward. Water from a wet hand runs to the back of the counter and pools against the wall, and you wonder in two years why the back-splash is delaminating.
The real install is to laser the floor, scribe the toe-kick to the slope, and shim the cabinet box behind the kicker so the box sits dead level. The countertop cantilevers off a true reference. Water flows to the drain. Drawers close.
Every "weird" vanity I get called to fix has a level on the counter that reads off by a full bubble. The vanity is not the problem. The install was.
4. No proper exhaust vent run
This is the one that grows mould inside your walls without you ever seeing it. The bathroom fan turns on. Air goes up into the ceiling cavity. The duct that should run to the outside of your house instead dumps into the soffit, into the attic, or into a flex hose that sags so badly water pools in the low spot.
In Ottawa winters that warm wet air hits cold sheathing and condenses. The condensation drips back down. Within two years the rafters near that drop point have black mould. Within four years the insulation is wet and useless. The homeowner has no idea until they hire a roofer for an unrelated job and the roofer texts them a photo.
A proper vent run uses rigid metal duct, runs in the shortest path possible to a wall cap or roof cap on the outside of the building, and gets wrapped in insulated sleeve through any unconditioned space. The fan itself needs to be sized to the room. Code is a minimum of 50 CFM continuous or 100 CFM intermittent for a typical bathroom. We size larger when the room exceeds 100 square feet.
What this looks like when it is done right
A bathroom we finished in Westboro last winter took us 22 working days. Five of those days were behind the walls before any tile went in. The owner saw the difference because:
- We replaced 14 feet of joist that the previous renovator had scabbed over with plywood
- We swapped the bathroom fan from a builder special to a 110 CFM unit on a humidistat, vented through the roof with insulated rigid duct
- We re-strapped the ceiling so the fan housing sat dead flat to the new drywall plane
- We scribed the vanity toe-kick to the floor pitch in two passes
- We used a waterproof membrane on every wet wall instead of cement board alone
The visible finish on that bathroom is the same as any well-finished bathroom anyone can buy. The work behind the walls is what makes it last 25 years instead of five.
How to tell if your contractor is cutting these corners
Ask three questions before you sign anything.
What is the duct path for the bathroom fan, and where does it terminate? If the answer is "into the attic" or "into the soffit," walk away. Code in Ontario requires termination to outdoors.
Are you cutting and inspecting the subfloor before tile? The answer should be yes, every time. If they say "we can see from the top side," they cannot.
How are you levelling the new vanity to the existing floor? A real answer mentions a laser level, scribing, and shimming behind the kicker. A bad answer is "it'll be fine."
The cost of redoing the work versus doing it right the first time
I will give you a real Manotick example from last year. The owner had a bathroom renovated in 2022 by a discount contractor. They came to us in late 2024 because the floor near the toilet was spongy and the ceiling above the bath had brown staining.
We pulled the bathroom apart. The original crew had skipped the subfloor inspection (joist rot we had to repair), painted over the ceiling instead of finding the leak (the toilet flange was set on warped plywood), used a generic vanity over a 9 mm slope (the drawers had been rubbing for 18 months), and dumped the fan duct into the attic (mould on the underside of the roof sheathing).
To redo the bathroom properly, they paid for a second full renovation on top of the first one, plus the lost use of their primary bathroom for another 18 working days while we fixed it. By the time it was right, they had paid for the room twice and lived with a bad bathroom for two and a half years in between.
Had they hired the right crew the first time, they would have paid once. This is not unusual. We see it 6 to 10 times a year. The shortcut is not a discount. It is a deferred bill with interest.
What an honest first quote looks like
An honest bathroom quote in Ottawa for a primary bath strip-and-rebuild scales with size, fixtures, and finishes. A quote that looks suspiciously light for a full bath rebuild is almost always leaving something out, because the labour does not compress: plumbing rough-in, tile setting, cabinetry, counter, and fixtures each carry real installed cost, on top of framing, drywall, electrical, paint, and project management. A clear itemized proposal shows you exactly which of those lines are in scope and which are not, so you can compare quotes that actually cover the same work.
If you want a quote from a crew that does these checks every time, our bathroom renovation page walks through our full process. Or call 613-862-4555 and we will send a project manager out for a free 48-hour feasibility review.
The shortcut always shows up on the second invoice. Better to write the check once.