job growth from energy efficiency retrofits ranges from low to highskilled jobs some of which will require training in the case of residential retrofit projects for instance most tasks will involve the installation of insulation and window replacement both of which tend to be more labourintensive than the heatingventilationair conditioning hvac or electrical work likely to occur on retrofit projects in large commercial buildings schrock schrock and sundquist insulation jobs are relatively lowskilled while window replacement jobs involve semiskilled carpentry experience regardless onthejob training may suffice as formal credentials in carpentry are usually not required