"Just Adding More Insulation" to Your Attic Isn't Always the Answer!

When homeowners consider improving their home’s energy efficiency and upgrade their attic’s insulation, one of the most common misconceptions we hear is: “Why not just add more insulation over the existing one?” While this seems like a quick and affordable fix, it does not always solve the problem and can lead to underperformance and even like mold proliferation.

The R-Value Trap: More Doesn’t Always Mean Better 

R-value is a measure of thermal resistance. The higher the R-value is, the better the insulation resists heat flow. So logically, adding more insulation should mean better performance, right?  

Not necessarily! 

In fact, If the existing insulation is underperforming due to air leaks, compaction, moisture, or mold contamination, then piling more material on top only masks the real issue and doesn’t fix it. 

Common Limitations of Adding Insulation Over Existing Material: 

• Air Leakage: This is the number one reason for attic insulation failure. If your attic has air leaks (from light fixtures, plumbing stacks, attic hatches, etc.), heat will continue to escape no matter how much insulation added. 
• Mold and Moisture: If your current insulation has been exposed to high humidity, roof leaks, or condensation, it may harbor mold. Trapping that mold underneath new insulation will result in this new insulation being also exposed and deteriorated.  
• Obsolete Insulation: Old fiberglass batts or cellulose that has settled won’t deliver its labeled R-value. Layering more on top won’t restore the original performance. 
• No Air Sealing: Without meticulously sealing the attic, you're still losing conditioned air from your home and allowing unconditioned air from the attic to circulate back into living spaces. Adding insulation is not the solution here. 

The Real Solution: A Complete Attic Energy Upgrade 

At Systèmes Éconergie, we recommend a complete insulation process that addresses not just R-value, but air sealing, mold decontamination, and moisture control Here's what the process looks like: 

 Step 1: Remove Old Insulation 

Safely remove all existing insulation materials, including fiberglass batts or blown-in cellulose. This reveals hidden problems like mold, rodent droppings and sources of air leaks. 

Step 2: Air Sealing 

We meticulously seal gaps, cracks, and holes in the attic floor using expanding foam and specialized materials. This dramatically reduces air infiltration and increases HVAC efficiency. 

Step 3: Mold Removal (If Needed) 

If mold is present, we apply a targeted antimicrobial treatment like our Mold-X2 to infected areas. This prevents regrowth and ensures the attic is safe and healthy before adding new insulation. 

Step 4: Install New High-Performance Blown-In Insulation 

We typically use blown-in cellulose for its excellent thermal resistance and eco-friendly composition. In addition, and unlike fiberglass, cellulose conforms to irregular surfaces and fills gaps more effectively. 

It is applied evenly to achieve the desired R-value (often R60 in Quebec for optimal energy performance). 

Adding more insulation to your attic without addressing the root causes of poor insulation performance is like putting a band-aid on a broken bone. For true efficiency and comfort, your attic needs a detailed inspection and tailored solution: air sealing, mold remediation (if necessary), and the installation of an adequate quantity of new insulation. 

Ready to stop wasting energy through your attic? Book your free attic inspection today!