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Why is My Window Leaking and How Can I Solve the Problem?

December 11, 2017

It’s not uncommon, when temperatures plunge, to feel cold air coming into a room. To say the least, its uncomfortable, but worse still it’s a sign of trouble. Window leaking is particularly obvious in the winter months, when cold wind and cold air have a habit of intruding.

The window leaking itself points to significant air leakage, either in the window frame or in the actual window structure. But either way, it makes for an uncomfortable room, a serious waste of energy (heating and cooling), and frustration about how best to solve the problem.

Why is my window leaking and how can I keep out the cold air?

Window leaking happens for a variety of reasons. Oftentimes, window leaking is a result of poorly installed windows. More than that, lower quality windows undergo wear and tear, and the sealing components wear out. The fact is, window leaking is much more than just an annoyance. When unresolved, it can promote mold and mildew, and even cause structural damage.

Beyond the intrusion of cold air, there may also be water deposits around the frame, especially after a rain. The bottom line is not to neglect leaking windows. They should be properly assessed by an experienced contractor and recommendations made with regard to repairs or retrofits. In a worst-case scenario, full replacement may be required but often there are effective fixes.

Some common causes of window leaks:

  • when there’s no rain, water deposits on windows is a sign of condensation
  • when water shows up inside the window panes, it’s a sign of a bad glass seal
  • when windows lose their “insulating gas” they can also accumulate moisture
  • loss of “insulating gas” can also significantly compromise energy efficiency
  • frame sealant may have deteriorated allowing air and moisture to intrude
  • water stains above the window frame are a sure sign that the wall is leaking

Preventing/resolving window leakage

Clearly, the best way to prevent windows from leaking is to install a high-quality product in the first place, and professionally. However, there are many options when it comes to remedies and repairs – most of which will make a big difference with air leakage and moisture collection.

One of the better solutions for window leakage is professional weatherization – a very effective way to block air leaks, stop cold air from infiltrating and prevent condensation from forming. This can be done with comprehensive draft proofing, window caulking, and weather-stripping.

To be most effective, weatherization techniques must be thorough. With problem windows, it means air sealing the window frames and any other source of air leakage. For the optimum in air sealing, homeowners would be wise to seal doorframes, ceiling lights, and heating registers.

Sealing windows and doors is essential to blocking air leakage and ensuring energy efficiency in a home. It will also provide indoor comfort, without uncomfortable drafts or fluctuating indoor temperatures. What’s essential is to weatherize with high-quality products, and have the work professionally managed. Shortcuts and DIY techniques may compromise long-term performance. 

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