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6 Signs Of Attic Mold

Mold Grows Quietly & Spreads Fast

Here are the 6 warning signs of mold in your attic space. 

  1. Discoloration on Wood in Attic
  2. Water Stains on the Ceiling 
  3. Poor Ventilation or No Gable Vents
  4. Roof Leaks
  5. Wet/Damp Insulation
  6. Musty Smell 

1. Check For Discoloration On Plywood 

Discoloration on plywood, black blotches, white spots all these can be signs of mold growth. One of the easiest ways to check for mold in your attic is to look for colored spots. Mold commonly possesses colors that stand out from its surroundings, such as, yellow, or white. Other colors to watch out for are gray and black. These are typically more harmful than other types of mold and tend to spread quickly throughout the attic. Black, however, is more of a concern. This is the color of the infamous black mold you often hear about being a problem in homes. Prolonged exposure to black mold can lead to severe health problems. 
2. Water Stains On The Ceiling

Visible Satins on your ceiling or walls. – Some people may not realize what mold looks like and think that it is merely dust or dirt that is staining their walls. Mold comes in many different colors, including gray, brown, green, white, and black. The moment you notice any visible signs of mold in your home, you may be in a very tough situation. This fact is particularly true if you see more mold the higher up you go in your home and spot dense mold growth in your attic: your roof is definitely to blame here.
3. Poor Ventilation or No Gable Vents

In our area Gable vents are highly recommend. If you walk around your home and notice there are NO gable vents, there is a big chance your attic might have mold. Homes with only ridge vents and soffit vents sometimes do NOT allow sufficient air flow. Soffits can easily get blocked by attic insulation and we know for our north eastern climate you cant skip out on insulation. 

Attic condensation happens during winter & spring months when warm and moist air from the main living area rises into the attic space and reaches the roof deck, the cold temperatures cools the air, condensing it back into a liquid form. These water droplets can lead to lots of problems for you as a homeowner, mold, rot and leaks.

Airflow is important! Gable vents offer passive ventilation of the attic space and roof. This allows cool air in and hot air out.  This prevents hot air from causing condensation on the inside of the attic. 

4. Roof Leak

A broken seal around a vent pipe or a popped nails, can cause water to leak in the attic space. Over time this causes the wood underneath to stay damp and wet. This makes perfect conditions for mold to grow and spread. ​We recommend a seasonal inspection during spring or fall as part of a standard preventative roof maintenance program. 

​Undiagnosed Water leaks, missing or worn out shingles can cause mildew damage, rotting fascia boards, flashing problems, and deterioration from seasonal weather conditions 

5. Moisture or Damp Insulation

Wet insulation means there is moistures in the attic. It could be from condensation or a roof leak. The source water needs to be correct and the insulation needs to be dried out.  When that insulation is exposed to moisture, mold can grow.  If insulation is left wet for long enough, mold and bacteria will start to grow in it. The longer wet insulation is left untreated the more mold spores grow and the greater the risk to your health and home becomes.

Insulation can be dried out but if its molded it may need to be replaced. Replacing insulation can be an expensive, time-consuming, and labor-intensive process, but it is also an issue that cannot be ignored. The moment you suspect your insulation is wet, you should check it out. 

6. Musty Smells 

There might be a problem in your attic, if you notice some unpleasant smells.  If you have a rodents up there you might smell urine and feces from their nesting material, or the smell of decay if rodents die and decompose. 
You should also be mindful if you notice a musty smell in your house. That musty smell probably stems from mildew or mold growth. Mold can grow in an attic if there is the presence of moisture, which may occur if you have a leak in your roof. One of the benefits of attic clean up sanitizing  is being proactive in addressing any musty smells, as unmitigated mold growth can contribute to allergies and respiratory issues.

If you different smells coming from the attic, this is a really strong sign that you should have an inspection of your attic and crawl space done for rodent removal.

CNY Roof Cleaners are professional and experienced roof inspectors that evaluate your roof’s and attic’s conditions and recommends roof maintenance centered on the existing roof’s age and other environmental factors, avoiding costly and unnecessary repairs. We do our best to resolve minor roof repairs and leaks; any repairs out of our scope notify the client after inspection and provide referrals to roofers or roofing installation company.
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