Side Effects of Overheated Attics
Gus Koedding • June 8, 2025
Attic Temperature with Dark Composition Shingle Roof
When it's 90°F (32°C) outside and the home has a dark composition shingle roof, attic temperatures can skyrocket due to heat absorption and poor ventilation.
๐ฅ Expected Attic Temperatures:
- Average attic temp under dark shingles: 130°F to 150°F (54°C to 66°C)
- In some cases (poor ventilation or no radiant barrier): it can reach up to 160°F (71°C)
โ ๏ธ Why It Gets So Hot:
- Dark shingles absorb more UV radiation.
- Heat radiates into attic space and gets trapped, especially if ventilation is poor.
- Radiant heat gain continues into the evening even after the air temperature drops.
๐จ Side Effects of Overheated Attics:
- Degraded insulation performance
- Warped roofing materials
- Increased cooling load on HVAC system
- Higher risk of attic mold growth due to trapped moisture and condensation at night
๐ ๏ธ Pro Tip:
Installing attic ventilation upgrades, air sealing, radiant barriers, or blown-in cellulose insulation with proper R-value can help bring those attic temps down by 20–40°F.

Attic mold foggers might sound like a quick-fix miracle in a can—but the truth is, they’re often more smoke than solution. Here’s a straight-up breakdown of the shortcomings of mold foggers when it comes to attic mold : ๐ซ 1. They Don’t Eliminate the Source Mold grows because of moisture and poor ventilation . Foggers don’t fix: Roof leaks Bathroom fans dumping into the attic Blocked soffits Air leaks from the home into the attic No matter how much fog you pump up there, the mold’s coming back if the conditions stay the same. โ ๏ธ 2. No Physical Mold Removal Foggers do not scrub, lift, or remove mold colonies . They only coat surfaces. Mold still needs to be: Brushed off Vacuumed with a HEPA system Treated with antimicrobial agents Dead mold spores can still trigger allergies and health issues—so leaving them there isn’t a win. ๐ชต 3. Poor Penetration on Porous Surfaces Attics are full of raw, porous wood —rafters, sheathing, joists. Foggers often can’t penetrate deep enough into the wood grain where mold roots have taken hold. That means: Spores may survive inside the wood Regrowth is likely, especially in humid climates ๐งด 4. Short-Term Fix, No Residual Protection Most over-the-counter foggers don’t leave behind a long-lasting antimicrobial barrier. Unlike encapsulation with mold-killing primers , foggers offer: No surface sealing No moisture resistance No long-term protection ๐งฏ 5. False Sense of Security Because foggers leave a scent and the mold "looks better," homeowners may think the problem is solved—but the underlying issue remains . This delays real remediation and can lead to much worse (and more expensive) problems later. ๐ธ 6. Cost vs. Effectiveness For DIYers, foggers aren’t cheap—and they don’t replace: Proper insulation removal Real mold remediation Ventilation correction So you're spending money to mask the problem rather than fix it. โ
Bottom Line: Foggers may help with odor control or surface disinfecting, but they’re not a standalone solution for attic mold. Real mold remediation requires: Source control (leaks, ventilation) Physical removal Disinfection with EPA-registered products Sealing with mold-resistant primers Insulation replacement if contaminated

Mold remediation isn't just spraying bleach and walking away. It's a multi-step process that requires proper containment, safety, treatment, and restoration. Here's a deep dive into the phases of mold remediation. ๐งฐ 1. Inspection & Moisture Source Identification What’s involved: Visual attic inspection Moisture readings (IR cameras or moisture meters) Identifying leak sources, venting issues, insulation saturation ๐ 2. Containment & Setup What’s involved: Sealing off the work area with plastic sheeting Creating negative air pressure (HEPA fan) Floor protection and access control ๐งผ 3. Insulation Removal (if contaminated) What’s involved: Attic vacuum system for blown-in or batt insulation Bagging and disposal of contaminated material ๐งช 4. Mold Cleaning & Disinfection What’s involved: Applying EPA-registered products (e.g., Vital Oxide , Benefect, Concrobium) Brushing/scrubbing visible mold HEPA vacuuming all surfaces ๐จ 5. Encapsulation What’s involved: Spraying mold-resistant primer/sealant (e.g., Zinsser Perma-White , Fiberlock Aftershock) Covering all exposed wood (rafters, decking, joists) ๐ฌ๏ธ 6. Ventilation Correction & Air Sealing What’s involved: Bathroom fan rerouting to exterior Unclogging soffits Installing baffles Sealing light can penetrations, top plates, pipes ๐งฑ 7. Insulation Reinstallation What’s involved: Installing new blown-in cellulose (often R-49 or greater) Final prep, air sealing touch-ups ๏ปฟ โ ๏ธ Notes on Pricing: Emergency jobs (flood/mold after storms) = higher labor rate Crawlspaces or tight attics increase time and hazard pay Licensed mold remediation companies often include limited warranties, which may increase overhead

Mold in the attic isn’t just an eyesore—it’s a serious problem that can wreck your insulation, damage your roof, and affect your health. Unfortunately, it often goes unnoticed until it becomes a full-blown issue. Whether you're in Spokane , Coeur d’Alene , or anywhere mold loves to hide, here's what you need to know. ๐ง How Do You Know If You Have Mold in the Attic? (Symptoms to Watch For) Most homeowners never think about their attic until there’s a problem. Mold usually develops silently, but here are the key warning signs: Musty or earthy smell upstairs or in rooms near the attic Stains or discoloration on ceilings or around light fixtures Increased allergy symptoms (sneezing, coughing, itchy eyes) without a clear cause Frost buildup on roof nails in winter (a sign of moisture) Dark or fuzzy patches on rafters, roof sheathing, or insulation High humidity or condensation in the attic If any of these sound familiar, it’s time to investigate—and fast. ๐ ๏ธ What Causes Attic Mold? Attic mold thrives on three things: moisture , organic material (like wood) , and poor ventilation . Here are the most common culprits: โ Bathroom fans vented into the attic โ Blocked or clogged soffits and lack of ridge/gable vents โ Roof leaks or ice dams โ Inadequate insulation leading to warm air intrusion โ Unsealed gaps around light fixtures or plumbing All of these create a moisture-rich environment perfect for mold growth. ๐งผ How to Get Rid of Attic Mold (The Right Way) Cleaning attic mold isn’t a DIY spray-and-pray job—it requires a professional mold remediation process to truly fix it. Here’s how we tackle it: 1. Inspection & Moisture Source Identification We perform a full attic inspection to identify not just the mold—but why it’s there. Bathroom fans, roof leaks, and ventilation issues are common offenders. 2. Attic Insulation Removal If your insulation is mold-contaminated, it has to go. We use a high-powered attic vacuum system to safely remove and dispose of infected materials. 3. Mold Treatment & Disinfection We apply professional-grade solutions like Vital Oxide to kill active mold spores. It’s safe, effective, and leaves no harsh chemical residue. 4. Encapsulation with Mold-Resistant Primer To prevent mold from coming back, we apply a mold-killing primer like Zinsser Perma-White to all exposed attic surfaces. This seals the wood and blocks future mold growth. 5. Ventilation & Air Sealing Fixes We correct any airflow issues—unclogging soffits, rerouting bathroom fans, and balancing intake/exhaust ventilation. We also air seal attic gaps to stop warm, moist air from entering. 6. Insulation Reinstallation We install blown-in cellulose insulation , which resists mold and pests, provides excellent R-value, and performs great in extreme temperatures. โ
How to Prevent Attic Mold from Returning Vent bathroom fans outside , never into the attic. Keep soffits unblocked and attic ventilation balanced. Install air sealing before insulating. Choose mold-resistant insulation like cellulose. Have your attic inspected regularly—especially after a leak, ice dam, or roof repair. ๐ฒ Serving Spokane & Coeur d’Alene with Trusted Mold Solutions At Pacific Insulation & Mold Remediation , we know attics inside and out. Our mold remediation services are built to eliminate the root cause , not just treat symptoms. From inspection to encapsulation, we stand by our work—and we do it right the first time. Think you might have attic mold? Don’t wait until it spreads. ๐ Call us today or schedule your attic inspection online.

Step 1 - Comprehensive Attic Inspection: A proper attic inspection isn’t just a quick peek under the hatch—it’s a full-scale diagnostic of your home’s hidden overhead ecosystem. In Spokane , Coeur d’Alene , and surrounding areas, we specialize in uncovering the hidden issues that wreck your insulation, create mold problems, and drive up energy bills. Here’s what we look for during a full attic inspection: โ
Roof Leaks & Water Intrusion: We check for active leaks, roof nail rust, staining, and damp insulation. Even a slow drip can lead to major attic mold or structural rot. โค Solution: Repair roofing, replace damaged decking, and dry out the area before mold sets in. โ
Improper Bathroom Fan Exhaust: A fan dumping humid air directly into the attic is a fast track to mold growth and soggy insulation. โค Solution: Vent fans through the roof or gable with a damper to the exterior—not into the attic. โ
Clogged or Blocked Soffits: Insulation can shift and block soffit vents, or they get clogged with dust, debris, or paint. This kills your attic’s ventilation and traps moisture. โค Solution: Unblock soffits, install baffles, and ensure free airflow from soffit to ridge. โ
Lack of Ventilation (or Wrong Type): We assess ridge vents, gable vents, and attic fans. Poor airflow causes heat buildup in summer and condensation in winter. โค Solution: Upgrade to a balanced system of intake and exhaust vents tailored to the attic's size. โ
Mold & Insulation Damage: We look for attic mold on sheathing, framing, and insulation. Damaged or contaminated insulation loses performance and becomes a health risk. โค Solution: Mold treatment, insulation removal , air sealing, and reinstallation with high-R-value materials like blown-in cellulose . โ
Rodent Infestation & Droppings: Mice love fiberglass nests, and their mess can ruin insulation and spread disease. โค Solution: Sanitize, remove soiled insulation, seal entry points, and reinstall clean insulation. A comprehensive attic inspection is the first step toward solving high energy bills, moisture problems, and indoor air quality concerns. We don’t just point out problems—we fix them Another important aspect of a comprehensive attic inspection is an air quality inspection. We test for various particulate and compounds including: PM2.5 (Particulate Matter 2.5) These are tiny airborne particles smaller than 2.5 microns—like dust, smoke, pollen, and mold spores. PM2.5 is a big deal for your lungs and can aggravate asthma, allergies, and other respiratory conditions. Formaldehyde (HCHO) A volatile organic compound (VOC) found in building materials, furniture, and flooring. Long-term exposure can be toxic. Often released by new construction materials, particleboard, and even insulation adhesives. Total Volatile Organic Compounds (TVOCs) This includes a broad group of chemicals emitted from paints, cleaning products, air fresheners, and more. High levels of TVOCs can cause headaches, fatigue, nausea, and irritation to your eyes and respiratory system. AQI (Air Quality Index) A general score combining all pollutants to give you a quick “good vs bad” air quality rating. Often color-coded from green (good) to red (danger zone). ๐ก Why It Matters (Especially in Attics & Homes): If you've recently dealt with mold , poor ventilation , or are finishing up attic insulation or encapsulation , a monitor like the M10+ helps verify that your air is safe to breathe. Step 2-Insulation Removal: When an attic is contaminated by mold, insulation removal isn’t optional—it’s essential. Mold spores embed themselves deep into the insulation, especially if it’s old, damp, or cellulose-based. Simply spraying disinfectant won't cut it. That’s where professional attic vacuum services come in. Using a high-powered insulation vacuum , we safely remove mold-infested materials to prevent spores from recirculating through your home’s ventilation system. This step is crucial before applying any mold treatment or installing new insulation. Leaving contaminated insulation behind means risking continued mold growth, structural damage, and poor indoor air quality. In the Spokane and Coeur d'Alene areas, where seasonal moisture and cold temps are mold’s best friends, fast and thorough attic insulation removal is key to stopping attic mold in its tracks and keeping your home protected long-term. Top reasons to vacuum out attic insulation due to mold: Prevent mold spores from spreading Remove contaminated, ineffective insulation Prepare the attic for mold treatment & encapsulation Ensure new insulation performs efficiently and safely Don’t let attic mold fester above your head— get it out, clean it up, and seal it tight. Step 3-Mold Treatment: We start by using a hospital-grade, powerful EPA-registered disinfectant and mold remover specifically formulated to kill mold at the root— not just bleach it out . It's non-corrosive, low-odor, and safe for use in attics , crawlspaces, and enclosed spaces where mold thrives. Ideal for attic mold remediation , it penetrates porous surfaces like wood, insulation, and framing to eliminate black mold , white mold , and other fungal growths without the harsh fumes or residue. It neutralizes odor, destroys mold spores , and prevents future growth with residual antimicrobial protection . Whether you’re dealing with black mold in the attic , harmless attic mold , or the kind that triggers a costly inspection report, our treatment is trusted by pros for its effectiveness, safety, and broad-spectrum kill power . Key Properties: Kills 99.999% of mold, bacteria, and viruses Approved by EPA for mold & mildew removal No rinse required on treated surfaces Safe for people, pets, and HVAC systems Eliminates mold odor at the source Ideal for use before attic encapsulation Perfect for: โ๏ธ Attic mold treatment โ๏ธ Mold in attic insulation or rafters โ๏ธ Pre- and post-insulation spray โ๏ธ Safe disinfecting without harsh chemicals Step 4-Encapsulation: Attic encapsulation is the final—and most critical—step in comprehensive mold remediation. After insulation removal, cleaning, and mold treatment, we apply a mold-killing primer like Zinsser Perma-White or Fiberlock Aftershock to fully seal exposed wood surfaces (rafters, sheathing, joists). This isn’t just for looks—it’s your first line of defense against future mold growth . Why it’s important: Even after visible mold is removed, microscopic mold spores can linger in porous wood. Moisture and poor ventilation can reactivate them, causing regrowth—especially in cold, damp regions like Spokane and Coeur d’Alene . A mold-killing, antimicrobial encapsulant bonds to wood, creating a durable, breathable barrier that: โ
Kills residual mold spores โ
Blocks moisture absorption โ
Prevents future mold colonization โ
Brightens attic space for easier future inspection โ
Extends the life of your insulation and structure Attic mold encapsulation is essential for homes with past water damage, poor ventilation, or fans that previously exhausted into the attic. If you want long-term protection, not a temporary fix, encapsulation is a must. Don’t just clean the mold— seal it out for good. Step 5-Air Sealing: Air sealing an attic is the process of locating and sealing all the hidden gaps, cracks, and penetrations in your attic that allow air to leak between your living space and the outdoors. These gaps are usually found around recessed lights, plumbing pipes, electrical wiring, attic hatches, and top plates. Why it’s important: ๐ Stop Energy Loss Without air sealing, your attic acts like a chimney—pulling heated air out in winter and letting hot air in during summer. That forces your HVAC to work overtime, jacking up your energy bills. Combine air sealing with proper insulation, and you’ll actually get the R-value you paid for. ๐ฌ๏ธ Prevent Moisture Problems & Mold When warm, moist air leaks into a cold attic, it condenses—and that’s a perfect setup for attic mold , frost, and rot. Air sealing keeps that moisture where it belongs: outside the attic. โ๏ธ Fight Ice Dams In cold climates like Spokane and Coeur d’Alene , warm air leaks into the attic and melts roof snow, which refreezes at the edges, forming ice dams. Air sealing helps regulate attic temperature and prevent these costly winter headaches. ๐ช Improve Comfort Drafty rooms, uneven temperatures, and cold floors upstairs are often caused by air leaks in the attic. Seal it tight and enjoy more consistent comfort throughout the home. Step 6-Insulation: If you’re insulating an attic in a place like Spokane or Coeur d’Alene , where temps swing from deep freeze to blazing heat, cellulose insulation is hands-down one of the smartest, toughest, and most mold-resistant options on the market. Here’s why cellulose earns the crown: ๐ง๐ฅ Extreme Climate Champion Thermal performance: Cellulose has a high R-value per inch (around R-3.7 to R-4.2) and fills every nook and cranny. It creates a dense, draft-stopping blanket that keeps warm air in during the winter and heat out during the summer. No gaps = no weak spots. Unlike fiberglass batts, it doesn’t leave cold pockets or allow airflow between pieces. ๐ฌ๏ธ Superior Air Sealing Dense blown-in cellulose helps limit air infiltration naturally. When combined with attic air sealing, it drastically reduces heat loss and ice dam formation. In harsh climates, this means lower energy bills, fewer hot/cold zones in your home, and a longer HVAC lifespan. ๐ก๏ธ Mold & Pest Resistance Treated with borates , cellulose is naturally resistant to mold, mildew, and insects. Borates act as a fire retardant and a biocide—meaning if moisture sneaks in, cellulose doesn’t immediately become a mold hotel like fiberglass often does. It also dries out faster than many insulation types, helping prevent long-term mold conditions. ๐ Eco-Friendly Bonus Made from recycled paper (usually around 85%), it’s one of the greenest insulation options available—and it performs like a beast. Bottom Line: If you’re dealing with attic mold , battling ice dams , or just tired of sky-high utility bills in an extreme climate, blown-in cellulose insulation gives you airtight performance, mold resistance, and energy savings that pay for themselves.