TDH Contracting

What Causes Skylight Condensation?

What Causes Skylight Condensation?

Table of Contents

Skylights are a great way to bring natural light into your home and enhance the look and feel of your living space. However, the main issue with skylights is skylight condensation. A frustrating problem for homeowners, skylight condensation can lead to water damage, mold growth, water staining and a range of other issues. These issues can often become costly for homeowners to put right. In this article, we explore skylights and what causes skylight condensation. We have also provided tips on how to resolve this problem!

As a Roofing Contractor, we have over 10 years of experience, working on skylight repairs and maintenance. With TDH Contracting, you are in safe, knowledgeable hands.

What Is Skylight Condensation?

Skylight Condensation is caused when water vapor in the air comes into contact with a colder surface, such as the glass of a skylight. When this happens, the two temperatures meet and condense into water droplets. This usually happens when the indoor air is warm and humid while the outdoor temperature remains colder. Skylight condensation is a common problem in most homes. The issue is much more prevalent during the winter months when the temperature difference is more significant, causing more condensation and water droplets.

Skylight Condensation

What Causes Skylight Condensation?

There are several factors that can contribute to skylight condensation. Each factor contributes to the creation of water droplets which can cause significant damage to your home. Understanding the cause of moisture through skylights will help to prevent condensation from forming in the future. The factors that contribute include:

  • Humidity Levels: High levels of humidity within your home are one of the main causes of skylight condensation. Cooking, showering or even breathing can release moisture into your indoor air, causing it to be more humid than the outside air.
  • Lack Of Ventilation: A lack of ventilation in your home can increase the likelihood of skylight condensation. Without good ventilation, your home can trap humid air indoors, meaning that the air inside your property is much more humid, before any level-increasing activities. Proper ventilation can help to circulate the air and reduce humidity levels.
  • Temperature Differences: The main cause of skylight condensation is temperature differences. The outside temperature is often different to the inside temperature. This means that one side of your skylight is a different temperature from the other. This causes condensation and moisture to form, often resulting in water droplets and damage.
  • Improper Installation: A poor skylight installation can often be the main cause of this issue. Poor installations often result in your property having a leaking skylight. If your installation isn’t installed or sealed properly, then the warm air can escape, causing a leaking skylight. This then forms condensation which results in water damage.

How To Prevent Skylight Condensation?

Understanding the causes of skylight condensation will allow you to take measures towards preventing the issue. Below, we have listed the steps you can take to prevent any condensation or moisture build-up in your home. If you are still suffering from the issue, we recommend that you speak to a roofing contractor such as TDH Contracting for further advice and guidance.

  1. Reduce Humidity: The first prevention method is to reduce humidity within your home. This can be done by using exhaust fans in bathrooms and kitchens, using a dehumidifier, or opening windows and doors to allow fresh air to circulate around your property. 
  2. Improve Ventilation: Another prevention method is to improve the ventilation within your property. Installing ventilation fans or opening windows and doors can help you to circulate the air throughout your home and remove the humidity within the air.
  3. Insulate & Seal Skylights: If you suspect a leaking skylight then you should look to seal your skylight. This reduces your leaking skylight from allowing warm air to leave your home. You can also insulate your skylight to keep it at the same temperature as your property, preventing the creation of water droplets and moisture.
  4. Install Skylight Covers: Another effective way of reducing water and condensation on your skylight is to install covers. These covers can help to insulate and reduce the temperature differences between indoors and outdoors.

How To Fix Skylight Condensation?

Preventing moisture and water from forming with your skylight is great. But what if you are already experiencing skylight condensation?

If you’re already experiencing the issue, there are several steps you can take to fix the problem.

  1. Remove Condensation: If you notice droplets or moisture forming on your skylight, you can simply wipe them away using a cloth or towel.
  2. Increase Ventilation: Increasing ventilation by opening doors and windows or using fans can help to reduce humidity levels and prevent condensation from reoccurring.
  3. Seal And Insulate: Sealing and insulating your skylights can help to prevent warm air from escaping and cold air from entering.
  4. Use Anti-Fog Products: Anti-Fogging Products can be applied to the surface of the skylight to prevent condensation from forming. These products work by forming a barrier on the glass to prevent moisture from forming.
  5. Replace The Skylight: If your skylight is old or damaged them replacing it with a new one could solve your issues. Newer installations mean new sealants and they are designed with better ventilation and insulation.


Skylight Condensation is a frustrating problem fo most homeowners. By addressing the issue, you can prevent damage to your home and reduce your costs. By understanding the causes of skylight condensation and taking steps to prevent/fix the problem, you can enjoy the benefits of natural light without the headache of water damage and mold growth.

If you take steps towards preventing or fixing moisture and notice the problem persists, we recommend that you contact a Roofing Contractor such as TDH Contracting. An experienced contractor will be able to look at your problem and recommend an effective repair.