Homeowners are often unaware that mold is growing on their windows until it has spread to the adjacent seal, sill, or jamb, or sometimes even farther to the apron and the surrounding wall. Especially when window sills and frames are partially obscured behind drapery, houseplants, or furniture, mold can flourish. Fortunately, you can avoid mold growth with routine window maintenance. If it does appear, it’s easy to recognize mold, and eliminating it is a straightforward process — if it hasn’t grown too extensively. 

Below is information on how to identify mold on your windows, eradicate it, and help prevent it from recurring.

How Can I Tell if My Windows Have Mold?

There are various reasons you may find that areas of your window frames have become discolored? Mold growth is one of those. Mold often starts growing along the bottom of window sashes or along the seam of the glass and the sash frame. 

Mold on window sills is typically black, white, brown, green, or one of several other colors, making it easy to see and identify. But some mold can appear the same color as the window frame or blend in with dust in the window track, making it hard to detect until it spreads. 

Is Black Mold On Window Sills Dangerous?

A small amount of black mold or other mold species on your windows is not usually harmful to people or property. But, sometimes, people do not know there is mold on a window until a significant amount has developed. 

A more dense and widespread mold accumulation can be hazardous to human health. Mold reproduces by releasing its spores into the air. That means people are at risk of inhaling those spores, which can be dangerous. Mold infestation presents the most severe risk to children, the elderly, and people with respiratory sensitivities. 

Mold proliferation can also damage or destroy wood window sills and frames and affect walls, carpets, wood flooring, draperies, blinds, or even the internal structure of your property. It can also destroy furniture, artwork, and other possessions near the mold-infested window(s).

Health and Safety During Mold Removal

When you undertake to remove mold from your windows, prioritize your health and safety. Be careful to prevent inhaling mold spores or exposing your skin to bleach:

  • Wear safety goggles.
  • Wear a protective mask over your nose and mouth.
  • Wear rubber gloves.
  • Open windows and/or doors for ventilation.

How To Prevent Mold On Windows

The cleanup process for mold removal is not complicated. The priority is to be sure you clean thoroughly to succeed in mold elimination and prevent recurrence of the problem. Here’s how to get rid of mold on window sill and sashes:

  • Make a cleaning solution of 1/4 bleach and 3/4 warm water. 
  • Cover the floor below the window before cleaning to catch any falling mold particulate. 
  • Use a soft cleaning brush to apply the bleach solution liberally and scrub the mold-infested window frame, sill, and other affected areas of the window. 
  • Use a clean damp cloth to remove the mold you loosened with the scrub brush.  
  • Use another clean damp cloth to wipe off any residue remaining on the surfaces.
  • Leave the window open until it is thoroughly dry. 

IMPORTANT: If there is a substantial amount of mold growth on walls, especially due to a leaking window frame, the infestation might be inside the walls, impacting the structural supports of your home. This may require professional mold abatement.

How To Prevent Mold On Window Sills and Sash

One of the most common causes of mold on window frames and sills is worn-out windows. Old windows often leak, allowing outdoor humidity, rainwater, and snowmelt to enter. Poorly performing old windows are also notorious for allowing excessive heat transfer, causing condensation on the interior side of the windows. 

There are multiple things you can do to help prevent mold from reoccurring on your windows:

  • Inspect windows periodically to ensure the glass, frames, seals, weatherstripping, and sills are good.
  • Replace leaky old windows with energy-efficient replacement windows to stop water leaks, and help slow heat transfer from causing extreme condensation. 
  • Control moisture in your home with adequate ventilation in the kitchen and bathrooms and wherever dust accumulation is highest. Consider using a dehumidifier, if needed.
  • Control the interior temperature by keeping the thermostat in your home set above 70 degrees. 
  • Routinely dust, damp wipe, vacuum, and mop to maintain windows properly and keep them free from conditions in which mold thrives. 

Advanced Window Products Energy Efficient Windows

Advanced Window Products manufactures today’s best energy-efficient replacement windows for homes. We offer a 100% satisfaction guarantee and a double lifetime warranty. Our customers buy factory-direct, which ensures the best product and service quality and eliminates the risk of typical warranty issues with third-party retailers. 

If it’s time to replace an old leaky window, call Advanced Window Products at (801) 505-9622, or contact us online to schedule a free in-home estimate!

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