Symptoms
- Every fixture drains slower than expected from move-in
- Previous owner may not have disclosed ongoing plumbing issues
- No specific fixture is dramatically worse than the others
- House and its plumbing are older or of unknown maintenance history
Likely causes
- CommonAging or partially blocked main sewer lineOlder homes can have a main line narrowed by scale, roots, or debris that the previous owner may have lived with.
- CommonNeglected fixture-level clogs throughout the houseYears of buildup in multiple traps and drains can make everything seem uniformly slow.
- PossibleLow household water pressure making drainage seem worse than it isSometimes it's a pressure issue rather than a drainage one, worth ruling out separately.
- PossibleVent system issues from age or a poor prior renovationMore likely in homes with additions or remodeled plumbing.
What to do
- Test each fixture individually to rule out multiple, unrelated local clogs before assuming a main line issue.
- Clean and clear at least a couple of the most convenient drains as a baseline test.
- If a couple of local fixes noticeably help those specific drains but overall sluggishness remains, it points more toward the main line.
- Consider having a plumber run a camera inspection of the main sewer line, especially valuable information to have early in owning an older home.
- Ask about the home's plumbing age and material (clay, cast iron, PVC) if available from inspection records, since older materials are more prone to this.
- Budget for potential main line work if a camera inspection reveals significant root intrusion, scale, or damage, since this is common in older homes.
Tools and parts
- Plunger
- Hand-crank drain snake
When to call a pro
Call a plumber for a main line camera inspection soon after moving in if all drains are slow, since it's valuable to know the condition of an older sewer line early.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.