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Slide-outs

RV slide-out leaking at the corners: start with the seal shape.

Slide leaks are frustrating because water can enter at the top, travel sideways, and show up at a lower corner. The visible drip is not always the opening.

Look at the wiper seal first

The outer wiper seal should flip the correct direction and sweep the slide wall as the room moves. If it folds under, tears, hardens or stays curled, rain can ride right past it.

Then check the bulb seal

The bulb seal is the thicker compression seal. It should touch evenly when the room is fully closed. A flattened spot, missing corner, loose adhesive or crooked room can leave a small gap that acts big in a storm.

Do a careful hose test

  1. Dry the inside corner completely.
  2. Have one person inside with a flashlight and towel.
  3. Start low and work upward with gentle water, not pressure-washer force.
  4. Test one area at a time: lower corner, side wall, top corner, slide roof, trim above the opening.
  5. Stop as soon as water appears and mark the outside test location.

Common hidden causes

Leaves on the slide roof, a damaged topper, bad corner trim sealant, cracked sidewall sealant above the slide or a room that does not sit square can all mimic a bad seal.

When alignment matters

If one side of the slide closes tighter than the other, or the reveal around the room is uneven, seal replacement alone may not fix the leak. Alignment should be checked before water damages the floor.