 I'm Corey with Tri-County Foam Insulation. So a friend of mine mentioned an ad he saw on TV about filling foam into existing walls to add to the insulation that already exists. Seems pretty slick, right? I'm sorry to say at first it will seem fine, but the product that is being used will start to shrink from all sides, which will greatly reduce the amount of foam insulation you paid for. All I'm saying is please make sure you know the products that are being used and do your research, because with us, experience makes a difference. Tri-County Foam Insulation.