Metal Roof Windows and Condensation

One of the common issues that many people face with metal rooflights can be condensation. Here we explain the common causes of condensation and how it can be avoided.

Condensation and moisture accumulation within our homes are inevitable consequences of daily activities such as cooking, washing, and even breathing. Typically, the air inside a home can manage and absorb this moisture, but issues arise when there is a significant temperature difference between the indoors and outdoors. One activity that significantly increases water vapor indoors is drying laundry inside, as the moisture released from clothes is absorbed into the indoor air.

As the colder months approach, we tend to keep windows and doors closed for longer durations, reducing the frequency of air changes within our homes. Everyday activities continue, contributing to a gradual increase in moisture levels. While heating can enhance the air’s moisture-holding capacity, there is still a limit to how much moisture it can contain. Rising energy costs often lead people to delay heating until absolutely necessary, exacerbating the problem.

A familiar example of reaching moisture saturation is the steam in a bathroom after a shower. The air can only hold so much moisture, leading to visible condensation on surfaces. Though not as dramatic as the bathroom scenario, daily activities generate significant moisture, leading to condensation in certain months.

Traditionally, condensation formed on window frames and glass due to temperature differences between the inside and outside. Modern homes with energy-efficient windows and construction methods aim to address this, but airtight designs can inadvertently increase the likelihood of condensation by limiting air circulation.

While modern windows and skylights are less prone to condensation, contemporary living practices contribute to higher indoor moisture levels. For instance, turning off heating at night allows moisture to deposit on colder surfaces when temperatures drop. New homes also absorb substantial moisture during construction, which is released into the indoor atmosphere during the drying-out period.

Efforts by architects and product manufacturers to design out condensation face challenges due to our lifestyles. Activities like cooking, bathing, and drying clothes, combined with airtight home designs, elevate the risk of condensation. Ignoring condensation can lead to damage to paint, curtains, wall coverings, and fittings, with the potential for costly repairs.

Despite advancements in glazing, steel-framed windows, and conservation rooflights may have a slightly increased risk of condensation, especially in modern buildings. The Glass & Glazing Federation provides a booklet on condensation causes and advice, emphasising the need for occupants to manage and mitigate condensation risks. This can be viewed on our downloads section.

In conclusion, condensation is a result of our lifestyle choices and the perception that modern products are maintenance-free. Understanding its causes enables us to take preventive measures and care for our products. Regularly clearing moisture from affected areas can extend the life of windows, rooflights, and ceilings while preventing the spread of mould patches.

Share this story

The Ultimate Guide to Conservation Rooflights

Independent expert advice for architects, builders and homeowners