RV Window Repair: Fixing Cracks, Leaks, and Foggy Glass

RV Window Repair: Fixing Cracks, Leaks, and Foggy Glass

The windows of your RV are more than just a view to the world outside; they provide natural light, ventilation, and a sense of connection to the great outdoors. However, these vital components of your mobile home can experience wear and tear over time. Cracks, leaks, and foggy glass are common issues that RV owners face. In this comprehensive guide, we’ll explore the methods and tips for repairing and maintaining your RV windows to keep them in top condition, ensuring your travels remain comfortable and enjoyable.

1. Diagnosing the Problem

Before you embark on any repair, it’s essential to understand the nature of the problem with your RV windows. Here are the common issues you may encounter:

Cracks: Cracked windows can occur due to impacts, extreme temperature changes, or stress over time. They can compromise the integrity of the window and lead to further damage.

Leaks: Leaky windows can cause water damage to the interior of your RV, leading to structural issues and mold growth. Leaks often occur around the window frame, seals, or gaskets.

Foggy Glass: Foggy or cloudy glass is a result of a broken seal between the double-pane windows. Moisture penetrates the space between the panes, obscuring your view and diminishing insulation.

2. Repairing Cracked RV Windows

Small cracks in your RV windows can sometimes be repaired, depending on their size and location. Here’s how to address this common issue:

Materials Needed:

  • Clear nail polish or epoxy resin
  • Plastic wrap
  • A razor blade or utility knife
  • Fine-grit sandpaper (600-grit)
  • Glass cleaner
  • Soft cloth

Repair Steps:

  1. Clean the Area: Use glass cleaner to thoroughly clean the cracked area and the surrounding glass.
  2. Apply Nail Polish or Epoxy: For small cracks, you can use clear nail polish or epoxy resin. Apply a thin layer over the crack and extend it slightly beyond the damaged area. Allow it to dry completely.
  3. Smooth and Remove Excess: After the nail polish or epoxy dries, use fine-grit sandpaper (600-grit) to gently smooth the repaired area. Be careful not to apply too much pressure.
  4. Clean Again: Clean the area once more with glass cleaner and a soft cloth to remove any residue.
  5. Cover with Plastic Wrap: For additional protection, cover the repaired area with a piece of clear plastic wrap. Trim any excess wrap with a razor blade or utility knife.

While this method can work for minor cracks, it may not be suitable for larger or more extensive damage. In such cases, it’s advisable to consult a professional for repair or replacement.

3. Fixing Leaky RV Windows

Leaky windows can lead to significant damage over time. Here’s how to identify and repair leaks:


  1. Inspect your RV windows for visible signs of leaks, such as water stains, mold, or wet spots on the interior walls or around the window frame.
  2. During a rainstorm, watch for water entering through the window frame or seals.

Repair Steps:

  1. Clean the Area: Begin by thoroughly cleaning the affected area to remove any dirt, debris, or old sealant.
  2. Apply Sealant: Use a high-quality RV sealant (such as silicone or butyl tape) to reseal the window frame and any seams or gaps where leaks may occur. Apply a generous layer, ensuring complete coverage.
  3. Smooth the Sealant: After applying the sealant, smooth it out with a caulking tool or your finger to create a watertight seal. Wipe away any excess sealant with a clean cloth.
  4. Allow to Dry: Let the sealant dry and cure according to the manufacturer’s instructions. This can take several hours to a day or more, depending on the type of sealant used.
  5. Test for Leaks: Once the sealant is fully cured, perform a water test by spraying water on the repaired area from the outside. Check for any signs of leakage on the interior.

4. Dealing with Foggy RV Windows

Foggy or cloudy windows can significantly affect visibility and insulation. Here’s how to address this issue:

Materials Needed:

  • Safety goggles and gloves
  • Drill with a small bit
  • Replacement desiccant packets (available online)
  • Clear silicone sealant
  • Screwdriver
  • Glass cleaner
  • Soft cloth

Repair Steps:

  1. Safety First: Put on safety goggles and gloves to protect your eyes and hands.
  2. Remove Window: To access the space between the double-pane windows, you’ll need to remove the affected window. Most RV windows are secured with screws; use a drill with a small bit to remove them.
  3. Remove Moisture: Once the window is removed, carefully open it, and remove any desiccant packets that may be present. These are used to absorb moisture but may become saturated over time.
  4. Replace Desiccant Packets: Insert new desiccant packets into the space between the panes. Ensure they are properly placed and secure.
  5. Seal the Window: Apply a thin bead of clear silicone sealant around the edge of the window frame where the two panes meet. This will create an airtight seal to prevent moisture from re-entering.
  6. Reinstall the Window: Carefully reattach the window using the screws you removed earlier. Tighten them securely but avoid over-tightening, as this can damage the window or frame.
  7. Clean the Exterior: After the sealant has dried, clean the exterior of the window with glass cleaner and a soft cloth to remove any residue.

Addressing foggy windows requires some DIY skills, and if you’re not comfortable with this process, consider consulting an RV repair specialist.

Your RV’s windows are essential for your comfort, safety, and enjoyment while on the road. Whether you’re dealing with cracked glass, leaks, or foggy windows, addressing these issues promptly is crucial to maintain the integrity of your RV. By following the repair and maintenance tips provided in this guide, you can keep your RV windows in top shape, ensuring clear views, insulation, and a comfortable environment for your travels. Remember that for more extensive repairs or if you’re unsure of how to proceed, it’s wise to seek professional assistance to ensure the job is done correctly and to preserve the long-term value of your RV.