Every uPVC window and door has a leakage problem, which can be fixed effectively. This guide will show you how to fix your uPVC window and door leaking problems effectively. Let’s learn!
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FREE QUOTE REQUESTWhy is My uPVC Window/Door Leaking?
uPVC window and door frames are actually designed with a built-in drainage system. When it rains or when moisture collects on the surface, the water isn’t meant to just slide off the outside, instead, it often runs into the frame and then exits through dedicated drainage holes. If these small holes become clogged with dirt, debris, or even insects, the water can’t drain properly. As a result, what you perceive as a “leak” may simply be water backing up inside the frame and finding its way indoors.
Do All uPVC Windows have Drainage Holes?
Yes, all uPVC windows should have drainage holes. These small holes are strategically placed at the bottom of the window frame to allow any rainwater that may accumulate inside the frame to drain out. This prevents water from pooling and potentially causing damage to the window frame, and surrounding walls, or even leading to mold growth.
Why Does my uPVC Window Leak When it Rains?
The most common reason for a uPVC window to leak during rain is worn or damaged weatherstripping. This rubber or plastic seal around the window can deteriorate over time, allowing water to seep through.
Why
How Do I Stop Water Coming Through my uPVC Window Frame?
Water leaking through your uPVC window or door frame usually results from blocked drainage channels, worn seals, or slight misalignments. By following these clear steps and using the right tools, you can stop the water intrusion and restore proper weatherproofing. The process is similar for both windows and doors, so you can apply these techniques confidently to any uPVC opening in your home.
Tools and Materials You Will Need:
Measuring Tape: For checking gasket sizes and ensuring proper alignment.
Soft Brush or Pipe Cleaner (1–2 mm thickness): For clearing debris from drainage holes.
Mild Detergent and Clean Cloth: For cleaning the frame and seal surfaces.
Exterior-Grade Silicone Sealant: Neutral-cure silicone is recommended; apply in a 5–7 mm thick bead.
Sealant Gun: To ensure a smooth, controlled application of sealant.
Replacement Gasket (if needed): Common gasket thickness ranges between 3–5 mm; measure your old gasket to match its thickness and profile.
Utility Knife or Gasket Removal Tool: To carefully remove worn or damaged seals.
Spirit Level: To check frame alignment (aim for as close to perfectly level as possible, within ±1–2 mm).
Step-by-Step Guide:
Inspect and Clear Drainage Holes (Typically 2–5 mm Diameter):
Your uPVC frame is designed with small drainage holes that let rainwater run off. Over time, dirt, leaves, and debris can clog these openings.
Use a soft brush or pipe cleaner (around 1–2 mm thick) to gently clear the holes.
Pour a small amount of water through the channels to confirm they are draining freely.
Clean the Frame Thoroughly:
Mix mild detergent with warm water and use a clean cloth to wipe down the frame. Focus on removing dirt or old sealant residue. Ensure the surface is dry and smooth before applying the new sealant.
Check and Replace Gaskets (3–5 mm Thickness):
The rubber gaskets around your window or door help form a watertight seal. If they are cracked, shrunken, or stiff, they need replacement.
Carefully remove the old gasket using a utility knife, taking care not to damage the frame.
Measure the thickness of the old gasket (usually between 3–5 mm) and install a matching replacement.
Press the new gasket firmly into the groove, ensuring it fits snugly and continuously around the frame.
Apply Exterior-Grade Silicone Sealant (5–7 mm Bead):
Load the sealant gun with exterior-grade silicone. Cut the nozzle at a 45° angle to control the flow.
Apply a bead of about 5–7 mm thickness along any gaps where the frame meets the wall or where water seems to enter.
Smooth the bead with a damp cloth or your finger for a neat finish.
Allow the sealant to cure according to the manufacturer’s instructions (typically 24 hours for full cure).
Check Frame Alignment (±1–2 mm):
Use a spirit level to ensure the uPVC frame is aligned properly. Even a slight misalignment of a millimeter or two can create gaps for water.
If necessary, adjust hinges or reposition the frame hardware according to the manufacturer’s recommendations.
Final Inspection and Test:
Confirm that no leaks appear inside.
Keep the drainage holes clean and inspect seals annually to maintain long-term performance.
Should UPVC windows be sealed outside?
Yes, uPVC windows should generally be sealed from the outside to ensure they remain weatherproof and properly protected against water infiltration.
Can you get UPVC windows resealed?
Yes, you can have uPVC windows resealed to restore their weatherproofing and energy efficiency. By resealing uPVC windows, you restore their ability to keep out moisture, reduce energy loss, and help maintain a comfortable indoor environment. This is a common and cost-effective way to extend the life and performance of your windows without the expense of full window replacement.
