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Leaky Windows Can Cause Mold Issues

by BrianReeves
window molds due to winter

Why is it that when we look at our windows, most of us aren’t surprised to see unsightly black spots, fuzzy growths and discoloration on or around the window frames and sills?
Although this is particularly true in older homes, brand new constructions can have equally devastating damage, and it’s usually linked to mold.
Mold around windows is one of the most common household problems, but many people don’t even realize the problem exists. They may look at it every day, but they often dismiss it without further thought.
This only makes the problem worse, and, in this blog, we’ll explain why.

How Does Moisture Lead to Mold Growth?
Mold spores are present in your home practically all of the time. However, when given a constant source of moisture, they begin growing and reproducing at incredible speeds, destroying any carbon-rich material in sight, including wood, ceiling tiles, wallpaper, paints, carpet, sheet rock and insulation.
Since mold grows best when it has a constant supply of moisture, getting rid of excess moisture is the key to preventing mold growth, especially around windows.
But since it’s impossible to completely eliminate all mold spores from your home, the best way to control mold is to keep your home dry.

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Where Does the Moisture Come From?
Moisture typically gets into your home through holes and gaps in walls, cracks in the foundation, and poorly sealed windows and doors.
Another source of moisture is condensation, which often occurs on windows because the glass tends to be cold. When warm, humid air comes touches this cold surface, it cools down and turns into a liquid.
If you have window mold, then it’s a good idea to check behind the frame or even behind the entire wall, as this will likely reveal a bigger mold problem underneath.

How to Check for Mold: Tips

So what can you do? How can you protect your home from nasty mold?
Well, checking it regularly for common indicators of moisture intrusion is crucial. Here are a few warning signs to look out for:

Water leaks
Where there is a leak, there is likely a mold problem. Leaks can happen in pipes, taps, roofs, basements, appliances and windows. Because they are often hidden (for example, behind walls or in attics), leaks can keep releasing water into your home for long periods of time, thereby fueling mold growth.

Water stains
Look for water stains on walls, floors and ceilings as they indicate past or present water intrusion. It is strongly suggested to also check behind the affected area to make sure that everything is dry and mold-free.

Warping or bowing of walls
Bowing is when the walls of a building start curving inward, in the shape of a bow. One of the most common causes of bowing is moisture intrusion and inadequate waterproofing. When water penetrates wood, drywall or another material, it can lead to bowing as well as major foundation damage.

Deterioration of wood
When it comes into contact with moisture, wood attracts various molds and other fungi that feed off of its nutrients. In these cases, the wood will decompose quickly, so it’s crucial to catch moisture infiltration early on.

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Bubbling or cracking of paint and wallpaper
A sure sign of moisture problems is bubbling or blistering paint. When a painted wall gets wet or when moisture is continually seeping through painted walls, a loss of adhesion occurs and bubbles form. The same is true for walls covered with wallpaper.

Unusual or persistent mold symptoms
The following symptoms are commonly associated with mold exposure. If you are experiencing any of them on a regular basis, your body might be warning you of a mold problem.
-Sore, watery or itchy eyes
-Skin irritation
-Runny or congested nose
-Coughing and sneezing
-Sore throat

How to Prevent Mold
If you want to minimize your chances of developing a mold problem, there are some simple things you can do around the house. Here are a few:
1. Keep indoor temperatures moderate to prevent condensation on walls and windows.
2. Fix leaks immediately. Don’t put off fixing a leaky toilet or pipe, as this will only make the problem worse.
3. Increase air circulation by regularly opening windows and doors.
4. Turn on exhaust fans when cooking and showering.
5. Use a dehumidifier if you feel that despite all of these efforts, the relative humidity inside your home is above the recommended 30-60%.
6. If your windows are old and allowing moisture to penetrate into your home, replace them with good-quality, energy-efficient ones.
Finally, by recognizing common signs of mold like stains and water damage around windows, you can detect mold problems early on, prevent major structural damage, reduce repair costs and live a happier and healthier life.
And if you have any questions, don’t be afraid to ask for help. The certified mold professionals at Mold Busters are experts in the field of mold remediation and are always here to help.

Bio: Ivan Ward – specialist at Mold Busters, professional mold removal and mold remediation company, from Ottawa, CANADA.

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Steeve April 29, 2014 - 7:50 am

Sometimes we can not prevent the mold in our homes, but as soon as you realize it in your home or in your office, is really important to contact a professional. The mold may cause serious illness.

Last month I had this kind of problem in my office, just called http://www.servpromartincounty.com/ and problem solved

A honing June 16, 2015 - 12:59 pm

I have a stucco home. Windows were leaking inside around the lower corners of window frames. The windows have since been replaced by company professional. There was already black mold formed inside the lower corners of the window and wall. This was left there When the windows were replaced. They were very well sealed and he guaranteed that they were perfectly sealed. Being stucco could moisture from rain or frost still be a problem

Mike September 11, 2015 - 8:59 pm

Great tips on spotting mold before it gets out of hand – so many expensive remediation jobs we’ve done could have been prevented with proper use of a de-humidifier.

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A. Ebel January 15, 2016 - 8:20 am

Lived in home since 1973. Never had a mold problem. Remodeled in 2009 – partially gutted interior, replaced all windows. All new paint and molding, tile & wood floors. Spots of black mold appeared 3 yrs ago in 5 or 6 small spots in bedrooms on ceiling above molding. Had it removed and spot repainted . Mold appeared n new spots last year always on ceiing, in rms with windows. had it eradicated and repainted. Now it has appeared in all rooms in a lot more places. In last 3 yrs have had a new roof put on, replaced an aged HVAC system 6 months ago. Have had attic cked for leaks, plumbers have explored beneath the house (beam & peer fndn. Must be these new windows??? Where do we go for help?

Mike May 23, 2016 - 8:08 am

Thanks for the tips. We see mold issues all the time on our industry (replacement windows). I know leaking windows and often the culprit, although they may not get near the blame that basement issues and roofing issues get.

Thanks for the tips!


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