Had a similar issue last year. Thought I'd fixed a minor drip under the kitchen sink myself—tightened the fittings, replaced washers, seemed all good. Didn't notice anything for months until I spotted some discoloration on the cabinet floor. Turns out that tiny drip had been slowly soaking into the plywood underneath, and by the time I caught it, mold had already set in. Had to rip out half the cabinet base and replace it completely.
I think people often underestimate how much damage water can do when it's hidden away like that. Even a small leak, if left unchecked, can lead to serious structural issues and mold growth. Learned my lesson—now I always double-check after any DIY plumbing fix and monitor closely for weeks afterward.
That's a tough one—seen it happen way too often. One thing I'd add is to always check behind and under the sink cabinet with a flashlight after any DIY fix. Sometimes leaks are so small they're invisible at first glance, but you'll spot moisture or discoloration early if you look carefully. Curious though, did you notice any musty smell before you saw the discoloration? Mold usually gives off a faint odor even before it's visible...
Good tip about checking behind the cabinet with a flashlight—saved me from a bigger headache once or twice. But honestly, sometimes even that doesn't catch everything. Had a tiny leak last year that was dripping so slowly it took weeks before I noticed anything off. No musty smell at first either, just a weird discoloration on the cabinet floor that gradually got darker.
If you're budget-conscious like me and still leaning toward DIY, here's what I'd suggest doing step-by-step:
1. Clear out everything under the sink completely (sounds obvious, but you'd be surprised how many people skip this).
2. Dry the area thoroughly with towels or paper towels.
3. Lay down some newspaper or paper towels flat across the bottom of the cabinet—this makes spotting drips way easier.
4. Run water through your faucet for a good 5-10 minutes while carefully checking all connections underneath with your flashlight.
5. If you don't see anything immediately, leave the paper towels/newspaper overnight and check again in the morning for any damp spots.
Doing this helped me pinpoint exactly where my leak was coming from without calling in a plumber right away. Turned out to be just a loose fitting I could tighten myself.
But here's something else to consider: if you're seeing mold or discoloration already, you might want to check further back behind the cabinet wall itself. Sometimes moisture seeps into drywall or flooring and causes hidden damage that's harder to fix later on (ask me how I know...). Have you checked if there's any softening of wood or drywall around there yet?
"Had a tiny leak last year that was dripping so slowly it took weeks before I noticed anything off."
Haha, been there myself—those sneaky little leaks are the worst. I once had a drip so slow it practically mocked me. I'd check every day, nothing... then suddenly, BAM, a dark spot appeared out of nowhere. Your paper towel trick is spot-on, by the way. I started using old cardboard boxes flattened out (eco-friendly bonus points!) and it made spotting drips super easy.
Good call about checking behind the cabinet wall too. Learned that lesson the hard way when I found out my "tiny" leak had quietly turned the drywall into mush. Ended up being a bigger DIY project than I'd bargained for, but hey, at least now I'm an accidental expert on drywall patching. You're definitely on the right track—just keep an eye out for any sneaky soft spots or discoloration spreading further back. You've got this!
Good tip on the cardboard—I usually stick with paper towels myself, but might give that a try next time. Honestly, I've learned to be extra cautious with kitchen leaks... had one quietly ruin the cabinet base without me noticing until it was way too late. Did you end up replacing any cabinetry, or were you able to salvage most of it?
