Drain is slow after a remodel or new fixture install

Symptoms

• Drainage was fine before recent renovation work
• Slowness started immediately after the new fixture or pipe work was completed
• Problem is isolated to the newly worked-on area
• Debris or residue visible in test water

Likely causes

• CommonConstruction debris (drywall dust, caulk, debris) left in the lineRenovation work can introduce debris that wasn't there before and settles in the new plumbing.
• CommonNew pipe run installed with insufficient slopeDrain pipes need a consistent downward slope to drain properly; too flat and waste won't clear well.
• PossibleFitting or connection installed incorrectlyA misaligned or improperly glued fitting can create a partial obstruction.
• Less commonUnrelated pre-existing clog coincidentally surfacing around the same timeWorth ruling out separately from the renovation work itself.

What to do

1. Run water and check if debris or discoloration comes through, which would suggest construction residue rather than a slope or fitting issue.
2. Try clearing the new line with a plunger or hand-crank snake to remove any loose construction debris.
3. If cleaning doesn't help and the problem is consistent regardless of how it's used, suspect a slope or installation issue with the new plumbing itself.
4. Contact whoever did the renovation work first, since installation issues are typically covered under their workmanship warranty.
5. If it's a DIY renovation, double-check the pipe slope with a level along its run, since drain pipes generally need about a quarter inch of drop per foot.
6. A pipe run with insufficient slope or an incorrect fitting usually needs to be corrected rather than repeatedly cleaned, since the slowness will keep recurring.

Tools and parts

• Plunger
• Hand-crank drain snake
• Level

When to call a pro

Call the contractor who did the work, or a plumber, if the slow drainage points to a slope or fitting issue rather than simple debris.

Safety