What Is a Sewer Cleanout and Why Does It Matter?
A sewer cleanout is a capped pipe that provides direct access to your home’s main sewer line — the pipe that carries all wastewater away from your house. It’s the access point plumbers use to inspect, clean, and clear your sewer line without having to dig or dismantle your plumbing. Most homes have one or more cleanouts, either inside the basement or outside near the foundation. Knowing where yours is — and keeping it accessible — can save you significant time and money when a sewer problem develops.
Most homeowners never think about their sewer cleanout until a plumber asks “where’s your cleanout?” — and the answer is a blank stare.
That’s completely understandable. It’s not exactly a glamorous part of homeownership. But knowing where your sewer cleanout is, what it looks like, and what condition it’s in is genuinely useful information — especially in an older London home where the sewer system may not have been serviced in years.
BEST Plumbing & Drainage has been working with London area sewer systems for over 50 years. Here’s what you need to know about cleanouts — and when yours might need attention. Questions? Call 519-438-6565 anytime.
What Does a Sewer Cleanout Look Like?
A sewer cleanout is typically a white or black PVC pipe, about 3 to 4 inches in diameter, with a threaded cap on top. Inside, it connects directly to your main sewer line. Outside, it usually looks like a capped pipe stub sticking out of the ground near your foundation. Inside the home, it looks similar — a capped pipe near your main sewer line, often in the basement or utility room.
In older homes, the cleanout cap may be made of brass or cast iron rather than plastic, and it may be recessed into the floor or partially buried under soil or mulch. If your home was built before the 1970s, the cleanout may be harder to find — or in some cases, may not exist at all.
How to Find Your Sewer Cleanout
Newer Homes (Built in the Last 45 Years)
In homes built within the last 45 years, the sewer cleanout is usually in one of two places:
- Outside — near the foundation, typically in the front yard along the path between your house and the street. Look for a capped pipe stub at or just below ground level.
- Inside the basement — near the floor drain or utility room, close to where the main sewer pipe exits the house through the foundation wall.
Older Homes
For homes built before the 1970s — which describes a significant portion of London’s housing stock — the cleanout may be harder to locate. A few places to check:
- Inside the basement near the main drain line
- Under the basement floor (sometimes covered with a cleanout cover flush with the concrete)
- Near the property line between your home and the street
If you genuinely can’t find a cleanout, it’s worth having a plumber locate it. In some cases, older homes simply don’t have one — and adding one is a relatively straightforward improvement that makes future sewer maintenance much easier and less expensive.
What Is a Sewer Cleanout Used For?
The cleanout gives plumbers direct access to your sewer line for:
- Video camera inspections — running a camera through the line to see blockages, root intrusion, pipe damage, or collapse
- Drain cleaning and hydro jetting — using high-pressure water to clear blockages and buildup from inside the pipe
- Root cutting — removing tree root intrusion that’s restricting or blocking the line
- Diagnosing recurring backups — when your basement drain keeps backing up, the cleanout is where the investigation starts
Without an accessible cleanout, any of these tasks becomes significantly more complicated and expensive — requiring either excavation or accessing the line through a drain opening further inside the house. Learn more about the benefits of video pipeline inspections and why they matter for older homes.
When Should You Have Your Sewer Line Cleaned?
There’s no universal answer, but here are the situations that call for sewer line cleaning:
You’re Experiencing Recurring Slow Drains or Backups
If multiple drains in your home are running slowly, if your basement drain backs up when you run the laundry or dishwasher, or if you’ve had more than one backup in the past year — your sewer line needs attention. See our article on basement drain backups for more detail on what causes this and what to do.
Your Home Is Older and Has Never Had the Line Cleaned
Many London homes were built in the 1950s, 60s, and 70s — some with original clay sewer pipes. A sewer line that hasn’t been inspected or cleaned in many years is likely carrying significant buildup and may have developing root intrusion. Wondering how long it takes to clean a sewer line in Ontario? A camera inspection is money well spent before a problem becomes an emergency.
You’re Buying an Older Home
A sewer camera inspection before purchasing an older home is one of the most valuable things you can do. A failed or severely damaged sewer line is a significant repair — and it won’t show up in a standard home inspection.
You Have Large Trees Near Your Sewer Line
If your front yard has mature trees — particularly maples, willows, poplars, or other species with aggressive root systems — an annual or biannual sewer inspection and cleaning is a smart preventive measure. Tree root intrusion is one of the most common causes of sewer backups in London’s older neighbourhoods. Read our article on 3 signs your sewer lines are blocked to know what to watch for.
General Preventive Maintenance
Even without any of the above warning signs, having your sewer line inspected and cleaned every 3 to 5 years is reasonable preventive maintenance for most London homes. It’s far cheaper than emergency service — and a lot less stressful than a basement full of wastewater.
What Happens if You Don’t Maintain Your Sewer Cleanout?
The cleanout cap itself can seize up over time — threads corrode, caps get buried under soil or mulch, or caps become extremely difficult to remove without breaking. In emergencies, a cleanout that can’t be opened quickly adds time and cost to any diagnosis and repair.
It’s worth checking periodically that your cleanout cap is accessible, hasn’t been buried by landscaping, and can be removed without excessive force. If you notice it’s seized, have it serviced before you need it urgently.
Why London Homeowners Call BEST
You’ve got questions about your sewer line. BEST has been answering those questions — and fixing those lines — in London and Southwestern Ontario for over 50 years. Here’s what sets us apart.
- Three generations, over 50 years. BEST was founded in 1972 by John Ashworth as a one-man operation. His son Shawn joined as a teenager and now runs the business — still hands-on, still on job sites. That continuity means something: the knowledge, the reputation, and the relationships built over five decades are still here every day.
- We show up and we follow through. Work is done on an agreed schedule. We are not satisfied until you are. That’s not a tagline — it’s been the standard since 1972.
- Licensed, insured, and accountable. BEST carries full licensing and insurance. We’re listed with the Better Business Bureau and hold a Contractor Check badge. You can verify who you’re inviting into your home.
- A 20-year warranty on qualifying work. Most contractors don’t offer anything close to this. The first 10 years of our waterproofing warranty are fully transferable to the next owner — real protection that adds real value to your home.
- Available when you need us. 24-hour service, 365 days a year. Same-day service is available. When your basement is flooding, you don’t want to wait until Monday morning.
Same-day service available. 24 hours a day, 365 days a year. Don’t wait for a sewer problem to become an emergency. Call BEST at 519-438-6565 to book a camera inspection or sewer line cleaning, or request service online. We serve London and communities throughout Southwestern Ontario.
Frequently Asked Questions
How do I know if my home has a sewer cleanout?
Check outside near your foundation along the path from your house to the street — look for a capped pipe stub at or near ground level. Also check inside your basement near the main drain. If you can’t find one, a plumber can locate it during a service visit.
What does it cost to have a sewer line cleaned in London, Ontario?
A professional drain cleaning typically costs between $200 and $500 depending on the method and severity of the blockage. A camera inspection is typically an additional fee. BEST provides a clear written estimate before any work begins.
Can I open the sewer cleanout myself?
You can try — if the cap is accessible and not seized. Use a pipe wrench on a threaded cap. Be cautious: if there’s a blockage in the line, opening the cleanout may release backed-up wastewater. If you’re not sure what you’re dealing with, call a professional first.
How often should I have my sewer line cleaned?
For most London homes, every 3 to 5 years as preventive maintenance. If you have large trees near your sewer line, older clay pipes, or a history of backups, more frequently — annually or every two years. After any backup event, a camera inspection is recommended to assess the condition of the line.
What should I do in a sewer backup emergency?
Stop using all water in the house immediately and keep people away from the affected area. Our sewer backup emergency guide walks you through the steps. Then call BEST at 519-438-6565 — we’re available 24 hours a day.
What is hydro jetting and do I need it?
Hydro jetting uses high-pressure water to scour the inside walls of your sewer pipe — removing grease, scale, debris, and roots far more thoroughly than a standard snake or auger. It’s the right solution for significant buildup, recurring blockages, or root intrusion. A camera inspection first tells us whether hydro jetting is warranted or whether a simpler cleaning will do.
