The super executive summary is this

"Changes in many extreme weather and climate events have been observed since about 1950. Some of these changes have been linked to human influences, including  a  decrease  in  cold  temperature  extremes,  an  increase in warm temperature extremes, an increase in extreme high sea levels and an increase in the number of heavy precipitation events in a number of regions."

Basically the events that most people see as extreme events hurricanes, droughts and floods have no evidence of a increase. However if you include very warm days as extreme events, then yes the IPCC does say there is an increase in 1 example of extreme weather. However those extreme events which have damages in the billions of dollars are not increasing, well, there isn't strong evidence for it.

All of this comes from page 53 of this documents http://www.ipcc.ch/pdf/assessment-report/ar5/syr/SYR_AR5_FINAL_full_wcover.pdf

The AR5 IPCC synthesis report from 2014.