When a South Florida homeowner says my house leaked during the storm, nine times out of ten the water came in through a window or a sliding glass door. Roofs get the headlines, but windows and sliders are where the volume of water actually enters most homes during a hurricane or even a strong summer thunderstorm.
The good news is that window and door leaks are mostly preventable with a few hundred dollars of maintenance, ideally done before hurricane season starts in June. The bad news is that most homeowners don't know what to look for, and most home inspectors don't either.
This guide is the checklist we wish every Miami, Fort Lauderdale, Boca Raton, and Palm Beach homeowner ran through every spring before the first tropical wave shows up off the coast.
Why windows and sliders leak in Florida specifically
Three factors that make Florida windows worse than windows elsewhere:
- Wind-driven rain. A Cat-1 hurricane drives rain horizontally at 70+ mph. Water that would never enter a window in a normal vertical rain finds its way through every imperfection in the seal.
- UV degradation. Florida sunlight breaks down silicone caulk, rubber gaskets, and polyurethane sealants 2 to 3 times faster than in moderate climates. A 20-year sealant is realistically a 7- to 10-year sealant down here.
- Saltwater corrosion. Coastal homes within a mile of the ocean experience accelerated corrosion of metal frames, fasteners, and locking mechanisms. Aluminum frames pit; steel reinforcement rusts; locks freeze.
A 15-year-old window in a coastal Florida home is well into its leak years.
The 8 common leak paths in Florida windows and sliders
These are the failure points we see most often:
1. Failed exterior caulk between the frame and the stucco. UV and thermal cycling crack the original sealant. Visible if you walk around the house and look at the perimeter of each window from outside.
2. Failed interior glazing seal between glass and frame. Older single-pane and early double-pane windows lose their glazing seal. Water gets between the glass and the frame, then drips inside.
3. Failed weep system. Windows are designed to let any water that enters the frame drain out through small weep holes at the bottom. Painted-over or clogged weeps redirect that water into the wall.
4. Failed gaskets at sliding door track. The rubber gasket along the bottom of a slider deteriorates. Wind-driven rain enters under the door and pools on the interior threshold.
5. Failed roller assemblies on sliders. Worn rollers let the door sit unevenly in its frame, opening gaps along the sides.
6. Failed locking mechanism on a slider. A locked slider compresses against the frame seal. A worn lock that doesn't fully engage leaves a slight gap that lets storm water in.
7. Cracked stucco around the window opening. Hairline cracks in stucco at the window corners are entry points for water that then travels behind the window's flashing.
8. Failed window flashing under the stucco. The original waterproofing membrane behind the stucco fails over decades. Even with perfect exterior caulk, water gets behind the stucco and into the wall cavity.
Items 1 through 7 are fixable maintenance. Item 8 usually requires removing the window and re-flashing — expensive, but worth doing if you find recurring leaks at the same window.
The pre-hurricane-season maintenance checklist
A 2-hour annual walk through your home should hit:
1. Inspect exterior caulk at every window and door.
- Walk the perimeter of each window. Look for cracks, gaps, or pulled-away caulk between the frame and the stucco.
- Re-caulk anything that's cracked. Use a high-quality polyurethane or silicone sealant rated for exterior, UV, and movement (Loctite PL S30, Sikaflex 1A, or DAP DynaFlex 230 are common picks).
- Don't paint over fresh caulk for at least 24 hours.
2. Check window weeps.
- Find the small holes at the bottom outside of each window frame. They should be open.
- Pour a cup of water on the interior sill of the window. After 30 seconds, it should weep out through the exterior holes. If it doesn't, the weeps are blocked.
- Clean weeps with a small wire or a needle. Don't enlarge them.
3. Inspect slider gaskets.
- Open every slider and run your finger along the rubber gasket on the bottom of the frame. It should be soft and pliable. If it's cracked, hardened, or compressed flat, replace it.
- Replacement gaskets are available from window/door manufacturers for $20 to $80 per door and install in 15 minutes.
4. Check slider roller wheels and tracks.
- A slider should glide smoothly when you open it. If it sticks, drags, or sits unevenly in the frame, the rollers need adjustment or replacement.
- Most modern sliders have adjustment screws at the bottom of the door — turn them to raise or lower the door so it sits evenly.
5. Test slider locks.
- Lock and unlock every slider. The lock should engage firmly. A worn lock that wobbles or doesn't fully engage compromises the storm seal.
6. Look at stucco around window corners.
- Hairline cracks at the corners of windows are common in South Florida stucco. Small ones can be sealed with elastomeric stucco patch. Large ones (more than 1/8 inch) suggest deeper movement and may need stucco replacement.
7. Check interior glazing.
- Look at the inside of each window pane. Cloudy spots, condensation between panes, or visible water tracks on the glass mean the glazing seal has failed.
8. Inspect storm shutters or impact windows.
- Accordion or roll-down shutters: test that they fully deploy and the locking pins engage.
- Bahama shutters: hinges should be sound; rotating wing nuts should turn easily.
- Hurricane panels: count them, label them by window, store them in good condition.
- Impact windows: glass should be uncracked; frame caulking should be intact.
What impact rated actually means
A common misunderstanding: impact-rated windows don't prevent water from entering during a storm. They prevent the glass from breaking and exploding into the home when struck by debris.
Impact windows still have to be sealed properly to prevent wind-driven rain leaks. An impact window with a failed weep, a cracked exterior caulk joint, or worn gaskets will leak just like any other window — it just won't shatter.
Florida Building Code requires impact rating (or shutters as an alternative) in High-Velocity Hurricane Zones (Miami-Dade and Broward counties) for any home built or substantially remodeled after 1994. If your home is older and hasn't been upgraded, you're still legally allowed to use plywood or panels as long as they're properly installed.
What to do during a storm if water starts coming in
Even with maintenance, no window is perfectly waterproof at 100+ mph. If water starts coming in during a storm:
- Move furniture away from the window. Don't try to block the leak with towels stuffed against it — the water will find another path.
- Open the weep system if you can identify it. If a weep is back-flooding into the room, you can sometimes drill a small relief hole into the bottom of the frame (interior side) to redirect.
- Lay down towels and trash bags on the floor to catch what's coming in.
- Photograph the leak. Time-stamped photos showing the water entering through a specific window with the storm visible outside establish wind-driven rain as the source — which is covered by homeowners insurance.
- Don't open the window to try to drain it. Wind pressure inside the home is more destructive than the water.
After the storm, document everything before any cleanup. Wind-driven rain damage is covered by standard Florida homeowners insurance; storm surge or flood damage is not.
When the maintenance isn't enough
If you've maintained the windows annually and you're still getting leaks during storms, the underlying flashing is probably gone. Replacing windows in Florida runs:
- Impact-rated double-hung: $700 to $1,500 per window installed.
- Impact-rated sliding doors: $2,500 to $6,000 per slider installed.
- Whole-house impact window upgrade: $15,000 to $50,000 depending on home size.
Florida insurance discounts for impact windows can offset 10% to 30% of the homeowners premium, which over a few years pays back a meaningful portion of the upgrade cost.
When to call RestoFlo
If a window or sliding door leak has already let water into your South Florida home, call us. We document the source for your insurance carrier, dry the structure, address any mold growth in the wall cavity, and rebuild what came out — including coordinating with a window contractor if the window itself needs replacement.
24/7 emergency line: (754) 289-4815.
