Best door sweep for sliding glass doors with uneven floors?

Uneven floors are a pain with sliding doors because a standard rigid sweep won't seal properly along the whole length. Your best bet is getting an adjustable or flexible sweep that can conform to the dips and rises. Look for ones with rubber or silicone fins that bend independently rather than staying completely rigid. The Pemko or similar heavy-duty adjustable sweeps work well here - they've got a track that slides up and down so you can position them to catch the worst spots, and the brush or rubber strip underneath handles the gaps.

For installation, measure your door width accurately and check the floor with a straightedge to see where the biggest gaps are. You might need to shim the sweep's mounting bracket on one side or use one of those sweeps with an adjustable tension mechanism. Some people go with a two-part approach: a rigid sweep where the floor's more even and swap to a flexible one under the area that dips. Make sure you're mounting it on the inside bottom of the door frame so it doesn't interfere with the sliding track itself.

If the floor variance is really bad (like more than half an inch difference), consider whether you actually need a full sweep or if a partial one covering just the problem areas makes sense. Weatherstripping on the frame sides might handle most of the air sealing, and then a smaller sweep tackles the worst spot. Just test fit everything before drilling holes - these uneven situations sometimes need tweaking after you see how the door actually moves across the floor.

Silicone tube sweeps are your answer - they compress and adapt way better than rubber to floor gaps, and you can shim the track itself with thin adhesive-backed weatherstripping to level things out before installing the sweep. If the floor dips more than a quarter inch or so, honestly your door frame might need shimming first, which sounds like overkill but takes maybe 20 minutes and solves the root problem instead of just masking it.