Door Leaking When It Rains: Trace the Glass, Sill, and Flashing

Use only checks that match the exact appliance or system and its official guide.

1. Check 1

   Before inspecting, stop if rain is accompanied by lightning, high wind, slippery surfaces, flooding, or an unsafe need to climb. Keep people away from cracked or loose glass. If water is near an outlet, appliance, doorbell, or other electrical equipment, avoid contact and isolate power only from a dry, safe location.

   Expected result: The area is unsafe or water is contacting electricity, or the leak can be observed safely from inside at floor level.

   Next step: Stay indoors during the hazard, contain water without leaning on the door, and arrange qualified help if electrical contact or structural damage is possible. Do not climb, open trim, or handle glass during the storm.

   Why this matters

   Why: Weather and electrical exposure can turn a window-and-door leak into an immediate injury hazard. A safe observation is enough to preserve the location and timing for later diagnosis.

2. Check 2

   On a dry day, inspect and photograph the interior from top to bottom. Mark the first wet point at the head, upper corners, side jamb, glass edge, lower corner, sill, or wall beside the frame; also note whether the leak occurs only with wind from one direction or with any rain.

   Expected result: Water starts at the glass perimeter or frame, collects at the sill, or appears above or outside the opening before reaching the interior.

   Next step: Use the location to select the next check, but do not assume the lowest drip is the source. If the wall or trim remains damp, document it and arrange a building-envelope inspection.

   Why this matters

   Why: The first wet point separates glazing and weatherstrip issues from sill drainage and wall-opening or cladding issues. Water visible above the frame can be entering from the head flashing, siding, roof edge, or another higher joint.

3. Check 3

   With the door closed and conditions dry, inspect the glass perimeter, glazing bead, weatherstrip, latch, and lock engagement from the accessible side. Look for a loose or damaged bead, cracked or missing sealant, torn or compressed weatherstrip, a panel that does not close evenly, or a lock that fails to pull the panel tight. Do not remove the glass or pry the bead.

   Expected result: The glass edge or sealant is visibly loose or cracked, weatherstrip is missing or crushed, the lock does not secure the panel, or these areas look intact.

   Next step: Clean only loose surface dirt and use the model-specific care instructions. Arrange qualified glass or door service for a failed glazing seal, damaged glass, a loose bead, or hardware misalignment; do not smear sealant over a moving joint as a permanent fix.

   Why this matters

   Why: Andersen explains that the primary glass seal is beneath the glazing bead and that weatherstripping can lose its seal through wear and compression. A door that does not close or lock properly can allow wind-driven water around the panel.

4. Check 4

   Inspect the lower sill, track, bottom sweep, and visible drainage or weep openings only when the surface is dry and stable. Remove leaves or loose dirt from an accessible opening with a soft brush or cloth if the product instructions allow it; do not caulk over a weep, drill the sill, or force a sweep into a tighter seal.

   Expected result: Water is pooled in the sill or track, a weep opening is blocked, the bottom sweep seals abnormally tightly, or the sill drains normally but water still enters.

   Next step: Clear only an accessible obstruction and observe the next dry-weather rain event without climbing. If the sill is damaged, the sweep is distorted, water remains trapped, or the leak continues, arrange qualified door service.

   Why this matters

   Why: Pella describes weep holes as the route for water in the sill and track to drain outward, and identifies clogged drainage holes or an over-tight bottom sweep as storm-door leak causes. A clear sill with continuing water keeps the upper seal and wall drainage in scope.

5. Check 5

   If the wet mark begins above the frame, at a side jamb, or inside adjacent trim, inspect from ground level for cracked exterior sealant, open joints, missing drip-cap or flashing details, damaged cladding, and a gutter or roof discharge aimed at the door. Do not remove siding, trim, flashing, or interior wallboard to chase the water yourself.

   Expected result: Water enters from above or beside the unit, wind drives it through a joint, trim is swollen or soft, or the exterior layers look intact.

   Next step: Keep a record of wind direction and rainfall, protect interior finishes, and arrange a qualified door or building-envelope inspection. Escalate promptly for soft framing, staining, musty odor, peeling finish, or suspected concealed rot or mold.

   Why this matters

   Why: The Department of Energy describes doors and windows as vulnerable breaks in the wall drainage plane and says properly integrated flashing should direct water out, not into the wall cavity. Hidden moisture can continue after the visible surface dries.

6. Check 6

   After the area is dry, compare the leak pattern with the door's operation: closes and locks evenly, glass stays seated, sill drains, and no new moisture appears in the wall or trim. Do not hose-test the door, seal the bottom edge shut, or apply a permanent bead of caulk until the entry path is identified.

   Expected result: The leak stops after a visible obstruction or drainage issue is corrected, or it returns at the same location during ordinary rain.

   Next step: For a repeat leak, give the technician the photos, first wet point, rain and wind direction, door type, glass configuration, and any prior repair history. Keep the opening protected without blocking intended drainage.

   Why this matters

   Why: A resolved accessible obstruction supports a maintenance cause. A repeat leak at the glass, frame, sill, or wall after safe checks indicates a seal, installation, movement, or drainage defect requiring a targeted repair.