Morningstar Inc. (MORN), a credit ratings agency previously focused on commercial real estate, will begin rating residential properties. Each rating Morningstar assigns to a residential mortgage-backed securitization will be reviewed monthly, with market changes factored into the rating. "We built our reputation in structured finance by providing investors with the gold standard of analysis for CMBS securities, a market that was traditionally underserved by the other ratings agencies," said Robert Dobilas, president of the credit ratings division at Morningstar. "With RMBS ratings and analytics, we intend to do the same for the RMBS market," he added. Morningstar plans to unveil the product at the structured-finance focused ABS East conference in Miami Oct. 16-19. The firm provides analytics for a large swath of financial services, in credit markets across the world. The announcement follows with recent expansion of the company's independent investment research. In August, Morningstar announced it would begin offering risk assessment on CMBS deals. The new risk assessment will monitor the potential boom in CMBS 2.0, the company said. Write to Jacob Gaffney. Follow him on Twitter @jacobgaffney.