How to Clean Window Tracks and Weep Holes So Rain Stays Outside

If you've ever watched rainwater sit in your window track and creep toward the inside of the sill, the problem usually isn't the window. It's the weep holes.

Most sliding windows have a few small slots along the bottom of the frame, on the outside. Those are weep holes. When rain gets into the track, which is normal, those slots let it drain back outside. When they're clogged, the water has nowhere to go. The track fills up, and sometimes it spills over into the interior window sill, where it can stain paint, swell wood, and start causing damage you don't want to deal with.

What I usually find in there

Typically, it's fine dust or soot that has collected over a period of time. With added moisture, it gets packed in there and clogs the weep holes. On occasion, you'll see a layer of paint or improper caulking right over them.

I wouldn't call that last one a common mistake. Most of the time it's just neglect of maintenance and not knowing the weep holes are there. But from time to time, somebody watched the wrong YouTube video and sealed them shut. Weep holes are supposed to stay open. Don't paint them and don't caulk them.

How to tell yours need cleaning

It's pretty easy to tell. Either you've noticed water building up in the track when it rains, or you can just see the track packed with dirt and dust.

Here's the part a lot of people get wrong. They give the surface of the track a good wipe-down and figure they're done. In reality, you're probably packing the drainage areas even tighter with whatever dust and debris was there.

Start dry, not wet

You'll want to avoid cleaning it with water or cleaner to start. Water turns all that dust and dirt into mud, and mud is a lot harder to get out of the track and the weep holes than dry dust is. Get the loose stuff out first.

How I clean window tracks and weep holes

1. Blow out the track. I like to start with a blower. My go-to is my mini Milwaukee blower. A shop vac with a brush or crevice attachment works too.
2. Cover the far end. Hold a rag over one side of the track while you blow into the other. Otherwise it can shoot dust and debris out the other side and make a bigger mess than you showed up for.
3. Loosen the weep holes. I work at it with forced air and a simple tool like a straight screwdriver to dig out the weep holes until I can blow through them freely. Go easy so you don't scratch or crack the frame. A pipe cleaner or small soft brush works for this too.
4. Give it a wash. Once I'm confident most of the dust and debris is out, I spray a vinegar solution into the track and the weep holes to give it a good wash. Mild soap and water works as well. Check your window maker's care guide first (Milgard's window and door care tips are a good example), since some brands ask you to stick with mild soap on their frames.
5. Do a pour test. Take a cup and pour water into the track, then watch the outside to see if it drains quickly out the weep holes.
6. Flush until it runs clear. Sometimes you'll need a few cups of water before it runs clean. That's how you know the track and weep holes are clear.

A little water sitting in the track after a rain can be normal. What you're looking for is water that drains out instead of filling up and spilling inside.

While I'm there: a fresh bead of caulk

This part isn't about the weep holes. It's about the inside of the window. When I'm doing this service and I think it's needed, I like to run a nice bead of caulk along the bottom edge of the interior window sill and, if needed, around the whole sill.

You see caulk cracking in those spots pretty often. It only takes several minutes and doesn't add much cost, and it gives the windows a fresher feel. If the outside seams around the window are cracked too, that's a different job, and my window resealing service covers it. I like to add it on when the customer lets me. Just to be clear, that caulk goes on the inside trim. The weep holes on the outside stay open.

Make it a yearly habit

Window makers recommend checking and clearing weep holes at least once a year, and before a stretch of heavy rain is a good time to do it. Here in San Diego, it's easy to forget, since we can go months without much rain. That's exactly how the dust builds up, and when the first real storm comes through, the tracks overflow. It's a good one to pair with the checks in my post on recaulking your windows before San Diego's rainy season.

Want me to take a look?

If your tracks are filling up when it rains, or you've spotted old paint or caulk over the weep holes, send me a photo. I work with homeowners around Chula Vista and the South Bay and across San Diego. I can tell you what I'm seeing and put together a quote. If you'd like a fresh bead of caulk on the inside sills while I'm there, just say so.

Window track and weep hole cleaning is a flat $60 per window (you can see all my set prices on my San Diego handyman pricing page). Above the first floor, I clean from inside only. If it's the only job, my $180 visit minimum applies.

Call or text (619) 815-7588, or reach me through the contact page. Text a photo of the window track and I'll take it from there.

— Preston, Unstoppable Handyman