Most window and door leaks aren’t leaks through the glass. They come from the joint between the frame and the wall: failed perimeter sealant, missing or damaged flashing, or a sill that sends water inward instead of out. In South Florida, where wind-driven rain hits buildings sideways every summer, those joints take a beating.
Window and door waterproofing means sealing and detailing those openings so water that hits them has a way out and never gets into the wall.
Where Windows and Doors Leak
- Perimeter sealant: The caulk joint between the frame and the stucco or concrete. It shrinks, cracks, and pulls away over time, especially on sun-facing walls.
- Sill and threshold: Water collects at the bottom of the opening. Without a sloped sill or sill pan, it runs into the wall below.
- Frame corners and joints: The corners of the frame itself can open up as the building moves.
- Glazing seals and gaskets: On storefronts and curtain walls, the seals holding the glass can fail.
- Blocked weep holes: Many window and storefront systems drain water through weep holes. If they’re painted over or clogged, water backs up inside the frame.
Signs Your Windows or Doors Are Leaking
- Water stains or bubbling paint below window corners
- Damp or crumbling drywall around the frame
- Musty smells or mold near windows
- Cracked, gapped, or missing caulk outside
- Water on the floor at sliding doors after a storm
- Rust stains on stucco below openings
How Window and Door Waterproofing Is Done
- Remove and replace failed sealant: Old caulk is cut out, the joint is cleaned and prepped, backer rod is installed where needed, and new sealant is applied at the right depth. Sealing over old caulk doesn’t last.
- Choose the right sealant: Silicone and polyurethane sealants are common for exterior perimeters. The right one depends on the frame material, the wall, movement, and whether it will be painted.
- Flashing and sill pans: On replacements or major repairs, flashing and sill pans direct water back out.
- Clear the weeps: Open drainage paths so the system can do its job.
- Water testing: On commercial storefronts and curtain walls, a controlled field water test can show exactly where water gets in before and after repairs.
Impact Windows Still Need Waterproofing
Impact windows and doors are built to resist hurricane-force wind and debris, and in South Florida they’re often required to carry product approval for high-velocity hurricane zones. But a strong window doesn’t make a watertight opening. The installation and perimeter sealing still decide whether water gets into the wall, so impact windows need the same inspection and sealant maintenance as any other.
How Often Should Window Sealant Be Replaced?
Exterior sealants typically last from several years to 10 or more, depending on the material, sun exposure, and how much the building moves. In South Florida’s heat and UV, sun-facing elevations usually wear out first. Inspect them every year, especially before rainy season, and replace them when you see cracking, separation, or hardening.
How Deluxe Waterproofing Helps
Deluxe Waterproofing’s waterproofing and caulking crews have sealed windows, doors, storefronts, and curtain walls on South Florida buildings for more than 80 years. We find where the water is getting in, replace failed sealants, and fix the details that caused the leak, for condos, commercial buildings, and homes across Miami-Dade, Broward, and Palm Beach.
Frequently Asked Questions
Why do my windows leak only during heavy rain?
Wind-driven rain pushes water into small gaps in perimeter sealant and frame joints that normal rain doesn’t reach.
Can I just add more caulk over the old caulk?
It rarely lasts. New sealant doesn’t bond well to old, failed caulk. The old material needs to come out first.
Do new impact windows ever leak?
Yes, if the installation or perimeter sealing isn’t right. The window itself may be sound while the joint around it lets water in.
Who fixes window leaks, a window company or a waterproofing contractor?
If the window itself is damaged, a window company. If the leak is at the perimeter, sill, or wall joint, a waterproofing contractor is usually the right call.