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Cynthia C. Shaw
Cynthia C. Shaw
Content Specialist

How to Properly Resealing Double Glazing for Energy Efficiency

Learn to resealing double glazing for better energy efficiency. Discover tips to maintain home insulation and boost your energy savings today!
Resealing Double Glazing

Table of Contents

Correctly sealed resealing double glazing windows are tight and are one of the things your house sways to make you. Making sure more windows are correctly sealed is sufficient. Properly sealing may save you a lot of money on energy costs, lessen your carbon footprint, and improve comfort. Double glazing acts as an insulator, keeping the warmth in during winter and the heat out during summer, which is crucial for maintaining a stable indoor temperature.

This guide will explain the importance of resealing double glazing, how to identify if it needs resealing, and the steps to do it yourself. You’ll also learn the signs of wear and tear, such as condensation between the glass panes, that indicate that your windows are no longer performing efficiently.

Whether you’re a homeowner looking to improve your property’s energy efficiency, a DIY enthusiast eager to take on a new project, or someone conscious about energy usage and environmental impact, this guide is for you. We’ll provide practical tips and detailed instructions to ensure you achieve optimal results, making your home more eco-friendly and cost-effective.

Understanding Double Glazing

Understanding Double Glazing

Double glazing refers to windows that have two panes of glass separated by a layer of air or gas, providing excellent insulation. Because your home will stay cool in the summer and warm in the winter, you’ll save money on your power bills and make better use of energy. The components of double glazing include:

  • Two Glass Panes: Tempered glass is usually used to make these panes, increasing their strength and longevity. Tempered glass also enhances safety, as it is less likely to shatter than regular glass.
  • Spacer: This component separates the two panes and is often filled with a desiccant to absorb moisture, preventing condensation within the window. The spacer material can vary, with some systems using metal while others use advanced materials designed to reduce thermal bridging.
  • Seals: These are very important for keeping the window’s structure and its ability to keep heat in. High-quality seals ensure that the air or gas between the panes does not escape, preserving the insulating layer that contributes to the window’s effectiveness.

In addition to these components, some double-glazing systems also include low-emissivity (Low-E) coatings on the glass to further enhance thermal performance by reflecting heat into the room. This combination of features makes double glazing an excellent choice for improving home comfort and energy efficiency.

Benefits of Double Glazing

  • Improved Insulation: Double glazing blocks a lot of heat, so it makes your house warmer in the winter and cooler in the summer. It enhances the energy efficiency of your living area and reduces your utility expenses.
  • Noise Reduction: The additional glass layer and the airspace between the panes provide a barrier that effectively dampens external noises, leading to a more serene interior environment.
  • Increased Security: Double-glazed windows are constructed with two panes of glass, making them much more challenging to break than single-pane windows. Further durability enhances the level of protection for your property, discouraging possible burglars and enhancing overall safety.

Signs Of Poor Sealing

Signs of Poor Sealing

Knowing when your double glazing needs resealing is essential for maintaining its effectiveness and ensuring energy efficiency in your home. Here are some signs to look out for:

  • Condensation Between Panes: This is a clear indicator that the seal is compromised and moisture has entered the space between the glass panes. Over time, this can lead to mold growth and further degradation of the window’s insulating properties.
  • Drafts: If you feel a draft near your window, even when it’s closed, the seal might be broken. Drafts can make your home less comfy and cost you more to heat or cool because your HVAC system has to work harder to keep the temperature where you want it to be.
  • Visible Gaps or Cracks: Check around the edges of the window frame for any visible gaps or cracks. These gaps can allow air and water to penetrate, reducing the window’s effectiveness and potentially damaging the surrounding structure.

Regularly inspecting your windows and addressing these issues promptly can help maintain the comfort and efficiency of your home.

Steps To Reseal Double Glazing


Steps to Resealing Double Glazing

It’s possible to do this project yourself as long as you have the right tools and follow these steps:


Tools and Materials Needed:

  • Utility knife or scraper: To remove any old sealant or debris.
  • Silicone sealant: This is used to create a waterproof and flexible seal.
  • Sealant gun: To quickly and evenly apply the silicone sealant.
  • Rubbing alcohol or window cleaner: This is used to clean the surface before applying the sealant.
  • Clean clothes: To wipe down the area and ensure it is dry and free of contaminants before sealing.

Step-by-Step Guide

  1. Remove the Old Sealant:
  • Gently scrape or use a utility knife to remove the old sealer around the window frame. Be careful not to damage the frame or the areas around it.
  • Ensure all remnants of the old sealant are entirely removed. You may need to use a brush or some fine sandpaper to get rid of any small particles or residue left behind.
  • After cleaning, dust and remove any remaining filth or dust using a damp cloth. This will make sure that the new sealant sticks to a smooth surface.
  1. Clean the Area:
  • Begin by thoroughly cleaning the area using rubbing alcohol or window cleaner to remove dirt, dust, or old adhesive residue. This step is crucial to ensure that the new sealant adheres properly and provides a strong, lasting bond.
  • Once the cleaner is on, gently scrub the surface with a scrub brush or sponge, making sure to focus on any tough spots.
  • Once the area is clean, wipe it dry with a clean cloth to remove any remaining moisture and ensure the surface is arid before applying the new sealant.
  1. Apply the New Sealant:
  • Load the silicone sealant into the sealant gun, making sure it’s securely in place.
  • Put a steady bead of sealer around the edge of the window frame to ensure you cover all the gaps and seams.
  • For a neat finish, smooth the sealant with a tool or your finger wrapped in a plastic bag. Press down slowly to fill in any gaps and make the surface even.
  • Before you touch or paint over the sealant, please wait for the amount of time that the maker says it should dry.
  1. Allow to Cure:
  • After applying the product, it’s crucial to allow it to cure correctly. Follow the manufacturer’s instructions for the recommended curing time, which is typically around 24 hours. It guarantees that the product establishes and adheres efficiently, delivering the best possible outcomes and long-lasting performance.

Diy Vs. Professional Resealing

DIY vs. Professional Resealing

Resealing your double glazing can be a cost-effective DIY project, but there are pros and cons to consider:

DIY Resealing


  • Cost-effective: You can save money by doing it yourself instead of hiring a professional.
  • Immediate action: You do not have to wait for a meeting to deal with the problem. You can do it as soon as you notice it.


  • Requires time and effort: DIY resealing takes a significant amount of your time and energy.
  • Potential for mistakes: If you lack experience, you might make errors that could lead to additional problems or expenses.

Professional Resealing


  • Expert finish: Professionals have the tools and knowledge to give your surfaces a smooth, perfect finish that can make them look much better and last longer.
  • Guaranteed results: A guarantee is often included with professional services to make sure that any problems will be fixed quickly and correctly.


  • Higher cost: Hiring a professional is typically more expensive than doing it yourself, as it includes labor, materials, and the expertise of trained technicians.

Consider hiring a professional if you encounter significant issues such as large cracks or extensive wear or if you need more confidence in your DIY skills. A professional can offer peace of mind and ensure that the job is done correctly the first time.

Long-Term Maintenance Tips


Long-term Maintenance Tips

Maintaining your double glazing ensures its longevity and effectiveness, keeping your home insulated and energy-efficient. Here are some tips:

  • Regular Cleaning: Regularly cleaning your windows and frames will keep them clear and stop dirt from building up. To keep the glass from getting scratched, use a soft cloth and a light soap.
  • Inspect Annually: Check seals and frames yearly for any signs of wear or damage. Look for gaps, cracks, or any areas where the sealant might be peeling away.
  • Prompt Repairs: Address any issues as soon as they arise to prevent further damage. Ignoring minor issues can cause bigger ones to happen, like drafts or condensation forming between the panes.
  • Lubricate Moving Parts: Ensure that locks, hinges, and handles are functioning smoothly. Apply a suitable lubricant to keep these parts in good working order.
  • Check for Condensation: If you notice condensation between the panes, it could indicate a failure in the seal, which may require professional attention to maintain the insulation properties.


Properly sealed double glazing is crucial for energy efficiency and comfort in your home. Well-sealed windows help keep the cold out in the winter and the heat out in the summer, ensuring a consistent indoor temperature.

By following these steps to reseal your windows, you can ensure they perform effectively for years to come, reducing drafts and preventing condensation. Take action today to improve your home’s insulation and save on energy costs.

You may save a significant amount of money on your future heating and cooling expenditures by making repairs now. For more in-depth tips or professional assistance, don’t hesitate to reach out to our experts. They can give you help and services that are specifically made to fit your wants.

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