Check out the UAD resources link below!  Good stuff!

For appraisals with an effective date (date of inspection) on or after September 1, 2011, the appraisal report must be completed in compliance with the UAD for conventional mortgage loans sold to Fannie Mae or Freddie Mac.

Fannie Mae has some great tools to assist appraiser in learning these changes.

https://www.efanniemae.com/sf/lqi/umdp/uad/index.jsp