What is Retrofitting Insulation?
Last updated February 13, 2026
Last updated February 13, 2026

Have you ever walked past an exterior wall of your house only to feel the winter wind coming through the insulation? Homes insulated 30 years ago have lost a substantial portion of their R-value over three decades. If your exterior walls feel cold to the touch in the winter or neglect to block the wind, a good way to lower your energy bills and make your home more comfortable is installing retrofit insulation. In fact, re-insulation can make your home a lot more energy-efficient and help you save money!
When it comes to installation methods, insulation retrofitting can differ from new home construction insulation, but the material choices are generally the same:
• Fiberglass
• Cellulose
• Spray foam
• Radiant barrier
Of these choices, non-expanding spray foam offers the least intrusive installation process paired with the most longevity and best energy savings.
Do You Need to Re-Insulate?
First things first—how can you even tell when it’s time? You may need retrofit insulation if:
• Your energy bills have been increasing
• It’s drafty and uncomfortable in your house
• Temperatures from room to room aren’t even
• The AC is running more than normal in the summer
While there are other signs of a poorly insulated home, these are the most common ones experienced by homeowners. Of course, you can always talk to a professional insulation company. And scheduling an energy audit, like a blower door test here, can help you determine your needs.
Get a free energy audit and discover how much you could save on your utility bills.
Get Your Free QuoteOwner & Founder
Chris didn't start RetroGreen Energy because he wanted to be in the insulation business. He started it because he wanted to fix homes the right way.
After earning his BPI Building Analyst certification and Minnesota Building Contractor license, Chris spent years studying how homes perform as systems. He saw firsthand that most comfort and energy problems weren't caused by old windows or outdated furnaces — they were caused by air leakage and inadequate insulation that nobody was diagnosing properly.
In 2009, he launched RetroGreen Energy with a commitment to doing things differently. Every project would start with proper diagnostics. Every recommendation would be based on data, not sales targets. And every homeowner would get the honest truth about what their home actually needed.
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