Why Is There Mold on my Windowsill and What To Do About It?

By: Nicole Patri

Recently, a homeowner called and asked if we could replace her windowsills without replacing her newly installed windows because there was mold growing on her sills on the outside of her windows. This outdoor mold could be caused by excess water and weathering over time. But, what if you’re experiencing this on the inside of your house- is it possible to replace the sill without replacing the window?

Q: Can I replace my windowsill without replacing my windows?

A: The quick answer to this question is yes! We can replace your windowsills without having to remove or disturb your existing window.

Q: Why is there mold on my windowsill?

A: Leaking windows and condensation are two of the biggest culprits of windowsill mold. We recommend having a contractor check your window seal to make sure that the mold isn’t caused by water getting through the window. Condensation is especially prevalent in bathrooms and kitchens because of the use of hot water and steam.

Q: Can you still replace my windowsill even if my current sill is moldy?

A: Yes, we can still replace your windowsill without disturbing your windows even if your windowsill is moldy. In this case, and in most cases when replacing windowsills, we recommend replacing exterior window trimming with a PVC windowsill.

The advantage of PVC windowsills is that they are resistant to moisture, able to withstand extreme temperatures, and are mechanical strength (able to withstand the stress of physical forces).

However, if your contractor finds that your windows are leaky, you might want to consider getting your windows replaced with a better seal. This will prevent all mold or mildew growth on your walls.

Call Almar (781-826-2577) today for any of your window or windowsill replacement needs.

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Almar Building & Remodeling Co (Hanover Ma). As a third-generation family-owned and operated company for over 60 years Almar Building has all the benefits of a small company with the options of a larger company. From Additions, Kitchens, Bathroom, Basement Renovations, Siding, Windows, to Doors Almar services the entire South Shore of Massachusetts including Hanover, Hingham, Pembroke, Norwell, Scituate, Cohasset, Duxbury, Hanson, Braintree, Weymouth, Milton, and many more towns, Why Is There Mold on my Windowsill and What to Do About It?

Craig Guido

With 20 years of remodeling experience both in the field and working in collaboration with homeowners to develop remodeling projects designed to fit your lifestyle.