What Causes Slow Bathtub Drains
Before you can fix a slow bathtub drain, you need to understand what's causing it. In Toronto homes, these are the most common culprits:
Hair Accumulation
The primary cause of slow tub drains is hair. Each bath or shower deposits strands that wrap around the drain crossbars and accumulate in the trap below. Long hair is especially problematic—it creates a net that catches smaller debris and grows into a substantial clog over weeks or months.
Soap Scum Buildup
Bar soap, body wash, and shampoo residue combine with body oils and minerals in Toronto's hard water to form soap scum. This sticky coating lines the inside of drain pipes and acts as glue for hair and other debris. It also narrows the pipe diameter, reducing flow even without a discrete clog.
Clogged Overflow Drain
The overflow plate (the round cover with holes below the faucet) connects to the drain system. Hair and debris can accumulate in this hidden area, restricting drainage. Many homeowners overlook this spot when troubleshooting slow drains.
Deeper Drain Line Issues
If your bathtub drain was fine but suddenly slowed without obvious cause, the problem may be further down:
- Tree roots entering older clay sewer pipes
- Partial main line blockage affecting multiple fixtures
- Collapsed or bellied pipe section
- Grease buildup from kitchen drains (if on same branch)
DIY Fixes for Slow Bathtub Drains
Try these methods in order, starting with the simplest. Most slow tub drains clear with DIY effort.
Step 1: Remove the Drain Stopper
Different tubs have different stopper mechanisms:
- Push-pull stopper: Pull straight up while twisting
- Lift-and-turn: Lift and rotate counterclockwise to unscrew
- Toe-touch: Push down, then unscrew counterclockwise
- Trip lever (in overflow plate): Remove overflow plate screws to access linkage
Once removed, use needle-nose pliers or a bent wire to pull out visible hair clumps.
Step 2: Plunge Properly
A plunger works on tub drains, but you must seal the overflow first:
- Stuff a wet washcloth tightly into the overflow opening
- Fill the tub with 2-3 inches of water
- Position cup plunger over drain and ensure good seal
- Plunge vigorously 15-20 times
- Check if water drains—repeat if needed
Pro Tip: Coat the plunger rim with petroleum jelly for a better seal against porcelain or fiberglass tub surfaces.
Step 3: Snake the Drain
A drain snake reaches clogs that plunging can't dislodge:
- Remove the overflow plate (usually 1-2 screws)
- Insert snake through the overflow opening (easier access than drain)
- Push while rotating clockwise until you feel resistance
- Continue rotating to break up or hook the clog
- Pull snake back slowly, removing debris
- Flush with hot water to clear loosened material
Step 4: Baking Soda Treatment
- Pour 1/2 cup baking soda down drain
- Follow with 1/2 cup white vinegar
- Cover drain and wait 30 minutes
- Flush with boiling water (or hot tap water for PVC pipes)
When to Call a Plumber
Some situations require professional equipment and expertise:
- DIY methods failed: After 2-3 attempts, the clog is too deep or stubborn
- Multiple slow drains: Tub, sink, and shower all affected—main line issue
- Water backs up elsewhere: Running tub causes water in shower or toilet
- Sewage odour: Indicates venting or deeper sewer problems
- Recurring clogs: Same drain clogs repeatedly despite cleaning
- Very old home: Pipes may be fragile or partially collapsed
Important: If water is completely stopped and backing up, don't use the fixture. Continued use can cause overflow and water damage. Call for same-day service.
What Professionals Do
- Power drain snaking: Motor-driven cables cut through stubborn clogs
- Hydro jetting: High-pressure water scours pipes clean
- Camera inspection: See exactly what's causing problems
- Diagnosis: Identify if clogs indicate larger issues
Toronto Bathtub Drain Cleaning Costs
DIY Costs
- Drain strainer: $5-$15
- Drain snake (manual): $10-$25
- Plunger: $10-$20
- Enzyme cleaner: $15-$25
Professional Service
- Basic drain snaking: $99-$175
- Power drain cleaning: $150-$250
- Main line cleaning: $200-$400
- Camera inspection: $150-$300 (often included with cleaning)
Prevention Tips
- Install a drain strainer to catch hair ($5-$15)
- Clean the strainer after each bath
- Run hot water for 30 seconds after draining
- Use enzyme drain cleaner monthly
- Brush long hair before bathing
- Don't let soap chunks go down the drain
- Clean overflow plate annually
Bathtub Not Draining?
We clear bathtub and bathroom drain clogs fast. Same-day service available throughout Toronto and the GTA.
Call (647) 554-4356Frequently Asked Questions
Why is my bathtub draining slowly?
Slow bathtub drains are usually caused by hair accumulation in the drain and trap, combined with soap scum buildup that traps debris. Other causes include clogged overflow drains, mineral deposits from Toronto's hard water, or problems further down the drain line. If multiple fixtures drain slowly, the issue may be in your main drain line rather than the tub itself.
How do I unclog a slow bathtub drain myself?
Start by removing the drain stopper and pulling out visible hair with needle-nose pliers. Try a plunger next—cover the overflow drain with a wet cloth, fill the tub with 2-3 inches of water, and plunge vigorously 15-20 times. If that fails, use a drain snake inserted through the drain opening or overflow hole. Finally, try baking soda and vinegar followed by hot water. Most slow drains clear with these DIY methods.
Can I use Drano in my bathtub?
Chemical drain cleaners like Drano can clear minor bathtub clogs, but they have drawbacks: they can damage older pipes (galvanized steel and cast iron common in Toronto homes), may soften PVC joints, and don't fully dissolve hair—they break it into pieces that can reform downstream. For occasional use in homes with newer PVC plumbing, they're acceptable. For older homes or regular maintenance, use enzyme cleaners or mechanical methods instead.
Why is my bathtub drain backing up into the shower?
When water backs up between fixtures, the clog is beyond the individual drain—usually in the shared drain branch or main line. This means the blockage is too deep for simple DIY methods. You need professional drain cleaning with a power snake or hydro jetter. Don't wait, as the situation will worsen and potentially cause sewage backup into your home.
How much does it cost to unclog a bathtub drain in Toronto?
Professional bathtub drain cleaning in Toronto typically costs $99-$175 for basic snaking and $150-$250 for stubborn clogs requiring power equipment. If the clog is in the main line rather than the tub drain, expect $200-$400. DIY methods cost $5-$25 for tools and supplies. Emergency or after-hours service adds 50-100% to standard rates.
How can I prevent my bathtub from draining slowly?
Prevent slow bathtub drains by installing a drain strainer to catch hair ($5-$15), cleaning the strainer after each bath, running hot water for 30 seconds after draining the tub, using enzyme drain cleaner monthly, and avoiding letting large soap pieces go down the drain. Brush long hair before bathing to remove loose strands. These habits prevent 90%+ of tub drain clogs.
Mike Thompson
Master Plumber & Drain Specialist
Mike has fixed thousands of slow and clogged bathtub drains across Toronto over 20+ years. He knows which DIY methods work and when to call for professional help.