Apr 15, 2019

Top 4 Reasons Why You Have Mold in Your Attic & What to Do About It

Attic mold thrives in warm, damp, humid environments.  Failure to pinpoint and address the source will only result in mold manifesting itself after clean-up has taken place.  Left ignored, a moldy attic can result in a breakdown of your roof’s structural components and attic sheathing.  This is one of the many reasons why insulation is a powerful tool for attic mold prevention.  Here are four common reasons attic mold growth occurs.

Leaky Roofs Can Lead To Attic Mold

Rafters, insulation, and sheathing with mold growth and discoloration are signals that the moisture source is a leaky roof.  Improper or weakened flashing around valleys, chimneys, and skylights can allow for water penetration into a home’s attic.  Ultimately, this will create mold.   


Improper Installation of Bathroom Exhaust Fans Causes Excess Attic Moisture & Mold

One of the biggest bath fan installation mistakes is having it vent into home’s attic instead of outdoors.  This approach introduces an unnecessary amount of moist air into the space.  When the warm, humid air encounters the attic’s cold roof sheathing, condensation takes place.  This leads to wet rafters and insulation, creating an environment for mold to thrive. 

Flawed Insulation: The Wrong Choice Can Cause Common Mold Or Black Mold In Attics

Attic insulation projects should be entrusted to reliable professionals that have a working understanding of building envelopes.  Opting for the wrong combination of insulation types or improper installation will trap the moisture that’s risen from the home’s lower levels.  With an inability to escape, the moisture will create an environment for mold to thrive.

Unsound Ventilation & Soffit Insulation Traps Moisture In Attic 

A common mistake insulation DIYers make is placing insulation in a home’s soffit vent.  Doing so prevents the vents from allowing in outside air to regulate a home’s attic temperature, creating a scenario that raises the attic’s temperature, allowing ice dams to form.  If ice dams cause water damage within the attic, it’s only a matter of time before insulation becomes saturated, allowing mold to grow. 

It’s vital that attic ventilation be balanced, allowing an equal amount of incoming and outgoing air.  Utilizing multiple ventilation systems in tandem can also lead to the creation of mold because the vents can cause moist air to circulate instead of dispelling it.     

Components That Make Up a 50 Year Roofing System & Prevent Attic Mold:

Is Mold In The Attic Dangerous?

Long answer short, attic mold can be incredibly dangerous to your health and to your home.  Unfortunately, out of sight does not mean out of mind when it comes to attic mold.  Moldy insulation should be removed, not only because it means the insulation’s properties are compromised, but also because of the health hazards associated with it.  Mold spores have the ability to circulate throughout your home.  This can lead to respiratory infections, eye irritations, compromised immune systems, and an array of allergic reactions. 

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What Homeowners Are Saying About Our Home Insulation Services:

“Thank you to the entire team for the outstanding job on the insulation job of my 100-year-old home!  Eric took the time to walk me through the entire process and even came back a second time to sort out venting questions.  Project manager, Randall, made sure the insulation installed met your quality standards.  Every member of your team worked very hard and didn’t end their day until the job was done right.  I look forward to energy savings and no critters in my attic!”

Pat M.
Bloomington, MN
July 26, 2022

"Eric is great. We used him on my mom’s house for several projects: new doors, windows, re-insulating the inside of the roof in upstairs bedrooms, tearing down & rebuilding the garage. My sister also used Eric to install LeafGuard® on her own house, build her a new deck, and install a metal roof. We recently had a meeting to discuss building a new deck for me, to replace the old one. We will be using no-maintenance materials, so no more sanding, staining, painting."

James N.
Minneapolis, MN
July 20, 2022

“We are very pleased with Lindus' work from start to finish. They did an energy audit, foam insulation of basement rim joists, removed and replaced damaged attic insulation with foam and cellulose, installed new attic access, replaced upper-level bathroom fan and exhaust to roof, removed and replaced soffit and fascia. We had storm damaged steel siding on front upper level of house. All of the siding on front upper level was replaced with LP® smart siding, all front windows were retrimmed. We believe they went above and beyond our expectations.”

David L.
Robbinsdale, MN
July 15, 2022

"We hired Lindus for attic insulation and new LeafGuard® Gutters. We had an issue arise a couple years after the work was completed. I called Lindus and had no problem scheduling someone to review and create a plan. Randal has worked diligently to get to the bottom of the problem and fix it permanently. The company truly does stand by their product, a claim that is not always realized, but with Lindus has proven to be true. I am so appreciative and would recommend them to anyone."

Sarah W.
Edina, MN
May 30, 2022

"They were contracted to insulate the garage ceiling which they did in a two-step process with both foam and blown-in insulation. They then returned to put up new gutters facia and soffits in a two day process that was professional, neat , and used materials economically."

Stephen G.
MInneapolis, MN
April 28, 2022

"Excellent and efficient work. Thankful that the Lindus crew was accommodating to our needs as homeowners and for their communication throughout."

Bloomington, MN
April 19, 2022
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