Expanding foam insulating system and method

A method and system for the application of foam insulation onto a surface or into a cavity include a sheet with an aperture, where the sheet covers or partially covers the surface or a cavity with the aperture adjacent to the surface or cavity. A pressure-activated foam generator which generates foam is coupled with the sheet. The pressure-activated foam generator includes a frangible output seal with a ruptured position. The pressure-activated foam generator is positioned so that in the ruptured position the foam has a path from the frangible output seal through the aperture and onto the surface or into the cavity. The sheet is connected to cover or partially cover the surface or cavity, and the pressure-activated foam generator is activated and the foam flows onto the surface or into the cavity.