RetroFoam
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Our utility has a number of customers who are using a company called RetroFoam to fill their exterior wall cavities and increase their insulation. I visited one customer this morning during an installation and took some pictures and video and asked questions.
Researching RetroFoam it seems that there are people who think its great and others that think its not. I’m seeing concerns about shrinkage over time, and whether its formula is any different than the bad old urea-formaldehyde insulation of 30 years ago.
Does anyone have experience with this product for retrofits? If so, I’d like to hear your input.
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I have a customer who is using Tripolymer 105. IMO the jury is still out on a number of possible issues including shrinkage, off-gassing, and whether or not moisture problems will follow. There are a few threads here on the topic.
What if anything are you hearing or learning on your end?
Retro has a rated %2 shrinkage. It isn't the old formaldehyde formula anymore. I've seen a number of retrofits, and people are gerally pleased with the results. It is rated at R-4.3 per inch.