If you just need to insulate a small area, or you have plumbing on an outside wall, this video is for you. Matt Risinger will show us how to get a ton of insulation into half the space of traditional insulation.Whenever Risinger is dealing with plumbing on an outside wall, he's got good insulation in place before the plumber starts to make sure we don't encounter freezing pipes on the wall. All he needs is some leftover rigid foam and a cheap can of spray foam. On a side note, don't forget that if spray foam gets on your clothes, they are totally ruined. If you're in the south, you want to have at least R10 behind the plumbing. In the north, you'll want R20. Watch as he cuts the sheet of rigid foam, leaving space to incorporate the spray foam (big-gap style). The spray foam will expand to do a great job at air-sealing. Once it dries, take a knife and shear it right off. Some products used in this videoSpray Foam - http://amzn.to/2tF6AT8Utility Knife - http://amzn.to/2tCRu0R