What is second mortgage Toronto? Second mortgages are loans you intentionally borrow against the value of your home. Your home, regardless it is a single-detached family house, a posh condominium or a humble townhouse unit, is an asset that will gain more value with the passing of time. Home equity lines of credit, or HELOC, is another term that can be used when you refer to second mortgages. Second mortgages can be used to put that asset into some other prolific goals or projects may be that you have.