Get a quote and call our team on

020 4587 8300

Request Quote
Leaking Windows - Causes & How To Fix Them


Leaking Windows – Causes & How To Fix Them

Myles Robinson
Written by Myles Robinson
Updated on 21st February 2024
Posted on 11th January 2024

Window Leaking Guide

Leaking Window

Facing leaking windows? Quick action can mitigate damage. This article explains the likely causes and delivers straightforward fixes.

installer fitting sliding patio door
Build your window today!
Get a Quote >

Arm yourself with the knowledge to prevent further leakage without unnecessary jargon or sales pitches.

Window Leaks - Summary

  • Window leaks can be caused by poor installation practices, ageing and deterioration of window components, and severe weather conditions, each necessitating different approaches for repair and prevention.
  • Early detection of window leaks is extremely useful and can be indicated by water stains, drafts, energy loss, or condensation; addressing these issues promptly can stop more serious damage.
  • Preventing future leaks involves regular window maintenance, upgrading to energy-efficient windows with improved seals, and ensuring proper installation by professionals to mitigate the risk of water intrusion.

Why Do Windows Leak?

Window leaks can be a homeowner’s worst nightmare, causing structural damage, mould growth, and increased energy bills. But what causes window leaks?

The answer isn’t as straightforward as you might think. Understanding the reasons behind window leaks can help you put a stop to them and save you from potentially expensive home repairs.

Window leaks primarily stem from three sources: improper window installation, ageing and wear of the window, and extreme weather conditions. Each of these factors plays a significant role in why windows are leaking, and understanding each can guide you to the right solutions to fix window leaks.

Poor Window Installation

Window leaks often result from substandard window installation. Whether it’s a new installation or a replacement, if the window is not properly installed, it can lead to major problems down the line. But how does poor installation result in window leaks?

The key to understanding this lies within the intricacies of the installation process. For instance, improper installation or absence of flashing can result in the infiltration of moisture into the window opening, resulting in leaks.

Effective sealing is vital in blocking the formation of air channels between the wall and window, which can lead to leaks.

If the window flashing is compromised or if the house wrap is substituted for proper flashing, it can lead to water infiltration into the wall structure of the house. Accurate measurements and the careful installation of windows, ensuring an exact fit, are indispensable steps to prevent potential window leaks.

Window Age and Wear

With time, window components can degrade, resulting in weakened glass seals or worn-out weatherstripping. This deterioration allows water to penetrate the home and can also impact the window’s insulation effectiveness, causing leaks. But what exactly happens as windows age and wear?

The propensity for leaks in ageing windows is often due to worn components, faulty seals, or degrading materials, which result in leak-prone windows.

Typical material deteriorations include difficulty opening windows, excessive window condensation, draughty windows, rotten window frames, broken window panes, and leaking.

Over time, the seal can be damaged by water, sun exposure, and temperature variations, resulting in window seal failure and the occurrence of leaks.

Weather Conditions

Leaky windows can also be a consequence of severe weather conditions. This is especially true for homes located in regions that experience heavy rain or snow. But how exactly do weather conditions contribute to window leaks?

Extreme weather conditions can breach window defences, especially when flashing or sealant is damaged or missing, resulting in windows leaking water. In times of heavy rain or snow, windows that lack proper protection or have not been regularly maintained are more prone to water intrusion, resulting in leaks.

Get a fixed quote

Identifying Leaking Window Issues

Before you get ahead of yourself and start calling someone to fix it, you should first identify what the actual problem is and how it is being caused.

Detecting window leaks is an essential measure to avoid potential home damage. While it can sometimes be obvious, like water dripping down your window frame during a storm, other times, it can be more subtle.

Old Window that can Leak

Understanding the signs of window leaks can help you catch and address the issue before it leads to more serious damage.

Indications of window leaks can vary from visible signs such as water stains and damage to subtle signs like drafts and energy loss, right through to condensation and moisture on the windows.

Each of these signs can indicate a potential window leak, but it’s important to understand what to look for to accurately identify the issue.

Water Stains and Damage

The presence of water stains and damage around the window is a conspicuous sign of a leak. But what exactly should you look for, and how do you know if the stains and damage are a result of a leaking window or something else?

Water stains around windows can be identified through the presence of discolouration on the walls or window sills, spotting or stains around the window, and common colours of discolouration such as brown, yellow, or copper.

However, it’s important to note that water stains or damage around windows can also be caused by other factors like water accumulation on the inside of the glass or deteriorated caulk or seals.

Draughts and Energy Loss

Drafts and noticeable energy loss can also indicate window leaks. This is often a less obvious sign, as it’s not something you can see but rather something you can feel or notice in your energy bills. So, how exactly do draughts and energy loss indicate potential window leaks?

Draughts are indicative of an air leak resulting from a gap or opening in the window seal, potentially indicating a leak.

Similarly, energy loss is a result of these air leaks causing temperature changes, leading to increased energy consumption and higher energy bills.

Condensation and Moisture

Another potential sign of a leak is condensation and moisture on windows. While these factors are often mistaken for unrelated issues, they can actually be significant indicators of a leaking window. But how exactly do condensation and moisture signal the presence of leaks?

Condensation and moisture on windows can often result from:

  • Damaged window seals, which compromise the insulation and temperature regulation of windows, causing heightened drafts and moisture penetration.
  • Inadequate insulation, which can result in condensation on windows as a result of the temperature disparity between the cold exterior and the warm interior air, causing moisture from the air to condense on the glass surface.
  • Insufficient ventilation results in an accumulation of excessive humidity within a confined space, which can also lead to condensation on windows (trickle vents can help to fix this and allow better air flow).

Leaking Window Repairs

Upon identifying a window leak, it’s vital to promptly rectify it to avert additional home damage. But where do you start? The most effective solution will depend on the cause and severity of the leak, but there are several common repair methods that can help.

From recaulking and sealing the window to replacing damaged components, there are a variety of ways to fix window leaks. In some cases, it may be necessary to hire a professional to assess and repair the issue, especially if the damage is extensive or the cause of the leak is not immediately obvious.

Recaulking and Sealing Window

Addressing leaking windows can be as straightforward as recaulking and resealing the window. But what exactly does this process entail, and how can it help prevent leaks?

Recaulking the window entails removing the damaged caulk and applying new silicone caulk to effectively seal any gaps or cracks around the window frame. This process can help stop water intrusion and the subsequent issues that come with it, such as mould growth and structural damage.

However, it’s important to note that recaulking a window is not always sufficient to fix a leak, especially if the leak is caused by more complex issues like poor installation or damaged components.

Replacing Damaged Window Components

At times, a window leak may be due to a damaged component which requires replacement. But which components are likely to need replacement, and how can this help fix a leak?

Common window components that may need to be replaced include the seals, flashing, or even the glass itself. Replacing damaged components can help fix leaks and improve the window’s performance, ultimately preventing further water intrusion and potential damage to your home.

However, it’s important to note that this process can be complex and may require professional assistance to ensure the replacement is done correctly and effectively.

You also need to consider the cost of new windows and if the process if worth it in the long run.

Hiring a Professional

In certain instances, professional assistance might be required to evaluate and repair a leaky window. This is especially true for more complex issues or if the damage is extensive. But when should you consider hiring a professional, and what are the benefits?

Man Fixing Leaky Window

Hiring a professional to evaluate and remedy leaking windows can provide numerous advantages, such as:

  • Assured work that can result in long-term cost savings
  • Enhanced safety and security
  • The requisite expertise and proficiency to deliver optimal services and efficiency

Professionals are equipped with the necessary tools and knowledge to correctly identify the cause of the leak and implement the most effective solution, ensuring that the issue is properly addressed and preventing further damage to your home.

Get a fixed quote

Prevent Future Window Leaks

Now that you've sorted out your leaky windows, it's time to make sure this doesn't happen again in the future for your own happiness and your wallet.

While rectifying existing window leaks is vital, prevention remains paramount. By taking proactive measures to stop window leaks, you can save time, money, and the potential hassle of dealing with damage down the line. So, what steps can you take to deter future window leaks?

To put a stop to future window leaks, regular window maintenance is necessary, along with upgrades to energy-efficient windows, such as a picture window or uPVC window, and guaranteeing correct installation.

Each of these measures plays an important role in stopping leaks and maintaining the integrity of your windows.

Regular Window Maintenance

Routine window maintenance plays an instrumental role in leak prevention. This involves checking your windows regularly for signs of damage, cleaning drainage channels, and keeping an eye out for any issues that could lead to leaks. But what does regular maintenance entail?

Recommended regular maintenance procedures to prohibit window leaks involve conducting annual inspections for peeling caulk, cracks in the glass, gaps around the edges, and peeling paint.

Regular window cleaning also plays a significant role in preventing leaks by maintaining the cleanliness and integrity of window seals.

By engaging in these regular cleaning practices, the potential for seal damage is reduced, thus ensuring the proper functioning of windows and ultimately mitigating the risk of water intrusion.

Upgrading to Energy-Efficient Windows

Switching to energy-efficient windows can be beneficial in stopping leaks. These windows are designed with features like double glazing and improved seals that not only help improve your home’s energy efficiency but also help stop leaks. But how exactly do energy-efficient windows prevent leaks?

Energy-efficient windows aid in preventing leaks by incorporating enhanced sealing, caulking, and weatherstripping, effectively reducing the passage of air and moisture.

Materials such as uPVC, aluminium, fibreglass, and metal or vinyl frames are commonly employed in the construction of energy-efficient window frames to improve their longevity and resistance to leaks.

Proper Installation

Lastly, ensuring correct installation is vital to prevent window leaks. Whether it’s a new installation or a replacement, ensuring that the window is properly installed can help prevent leaks and improve the performance of your windows. But what does proper installation entail?

Proper installation requires precise fitting of windows to eliminate gaps that could allow water to enter. A professional window installer ensures this by using high-quality sealants and weatherstripping to create a watertight barrier on the window sill, which is essential in preventing water from seeping through and causing leaks. An improperly installed window, on the other hand, can lead to such issues.

Repairing Window Leaks - Our Thoughts

With this guide, you should now know that window leaks are a common issue that homeowners face. They can be caused by a variety of factors, including poor installation, age and wear, and extreme weather conditions.

However, by identifying the signs of a leak, implementing effective repair methods, and taking preventative measures, you can protect your home from the damaging effects of window leaks.

Remember, prevention is key - by taking proactive steps to maintain your windows and address any issues promptly, you can save time, money, and potential damage down the line.

Frequently Asked Questions

Why do my windows leak when it rains?

Your windows may leak when it rains due to damaged or missing sealant or caulk, which can be a common and overlooked cause.

To fix this, clear out any damaged caulk around the window and replace it with a new bead of silicone caulk.

How do you stop water dripping from windows?

To stop water dripping from windows, you can reseal the glass to the gasket with clear silicone caulk after checking for damaged caulking and cleaning the window frame.

Window Leaking

Why do windows leak in winter?

Windows often leak in winter because condensation forms on the glass when it is cooler than the warm, moist air around it, leading to drips and accumulation that resemble a leak.

What is the significance of proper installation in preventing window leaks?

Proper installation by skilled professionals ensures the correct fitting of windows with suitable sealing and weather resistance features, playing a big role in preventing leaks. Professional installation is essential for preventing window leaks.

Is it worth upgrading to energy-efficient windows?

Yes, upgrading to energy-efficient windows is worth it, as they can prevent leaks and improve your home's energy efficiency.

They are built with enhanced sealing, caulking, and weatherstripping and are made from materials that improve longevity and resistance to leaks.

Get a fixed quote

Written by
Myles Robinson
Myles Robinson Managing Director
Posted on: 11th January 2024
Topic: Advice

Myles is one of our esteemed directors at Value Doors, dedicated to sourcing and fitting the best composite doors and windows. His mission is to offer our customers exceptional deals on energy-efficient composite doors, focusing on reducing costs while making sure the most advanced technology is readily available for installation. This commitment is what motivates Myles in the door industry.

More articles

Build Your Doors & Windows Online Design Online Here ➜