As the rainy season encroaches, you may notice some issues in the areas in and around your windows. Sometimes the evidence of moisture seems inconsequential or merely a nuisance, while other times it can appear to be more problematic. It's always best to address any moisture related issues sooner rather than later. What are some of the issues you're likely to come up against and what can you do to counter them?
Double Glazing Misting
If you have double glazing units installed in your home have you noticed that sometimes there will be evidence of "mist" in what is supposed to be the sealed interior cavity? This normally happens when a small pinhole appears in the rubber that runs around the sealed unit edges. Water vapour can then penetrate. Even though absorbent material is normally placed in this cavity (similar to the little bag of desiccant that you get when you purchase an electronic item), these quickly reach a saturation point in the rainy season. Then, whenever the temperature drops, vapour condenses into tiny droplets and will adhere to the colder surface of the glass. Unfortunately, misting of this type is very difficult to fix by yourself. You may well have to go back to your original installer, or ask your window repair company to replace the sealed unit.
If you notice that condensation is forming on the interior of the windows on the sills, this may well be due to infiltration through gaps around the edges of the windows. If you do see gaps between the frames and the masonry then you can use silicone mastic material to seal them.
Relieving Bridging Issues
However, even though you may not notice any obvious gaps you should bear in mind that some condensation can always form on the walls that are around the edges of the window frames. This is because the masonry in this area is effectively a bridge between the colder outdoor air and the warm interior. This issue can often be relieved by installing extractor fans that will expel the moistened air, or by generally improving the ventilation of the room to relieve the condensation.
Note that if you are in the process of replacing or repairing your windows or want to relieve the issue caused by dampness "bridging" once and for all, you should get your contractors to install special plastic "cavity closers" within the cavity between the outer and inner walls to remove the bridge.