The Reflectix would reflect back in your body or cooking heat. It's not going to have a role "keeping out cold". Van converters often use a mixture of foam boar

The Reflectix would reflect back in your body or cooking heat. It's not going to have a role "keeping out cold". Van converters often use a mixture of foam board insulation, Reflectix, spray on foam, etc to either keep out heat (in Summer) or keep in heat (in Winter).