We had fibreglass batts as insulation and it was becoming a mess as a result of animal nesting and genrally poor installtion. We hired GNI to remove the old insulation and install polyurethane foam. They were recommended by a competitor who doesn't have the equipement for this type of job as there are lots of irregualr surfaces. They removed a lot of materials that the fibreglass was behind and installed the foam carefully and precisely and cleaned up the old material. However, they ripped apart many surfaces and as a policy left them open with removed materials in a pile - which the salesman had not expected to happen. We had it repaired and things now are fine.