The changes will also allow a 39 per cent increase in fixtures between tier-one and tier-two nations, with tier-one countries touring the Pacific Islands, Japan, Canada, United States, Georgia and Romania.
Roux said the change to Super Rugby would be effective from 2019 - as June tours are not undertaken in Rugby World Cup years - even though the new calendar will only come into operation in 2020.
The Rugby World Cup will also begin a week earlier from 2023, starting in the second week of September.
Emerging rugby nations - including those mentioned above - will be integrated into the July and November windows, with World Rugby setting a goal of 110 Tier One vs. The agreement between the four home unions and New Zealand, Australia and South Africa ends after this summer's series against the All Blacks and there have been calls to cut trips from 10 matches to seven.
World Rugby yesterday announced its plans for a new global calendar that included breakthrough pledges to the Tier 2 rugby nations and also represents the possibility of a significantly improved Premiership club competition in England.
Rob Nicholl, the chief executive of the International Rugby Players' Association, backed the new set-up, which is due to run from 2020-2032 by saying: "We welcome the agreement of a calendar and appreciate the genuine consideration given to the player welfare needs of the world's top players throughout the process".
But with the 15-a-side code traditionally a winter sport in both the northern and southern hemispheres, all attempts to streamline the match programme have so far floundered, despite often repeated concerns about player welfare and burn-out.
The current June worldwide window will move to the first three weeks of July to allow the Southern Hemisphere club championship, Super Rugby, to be completed prior to the matches.
"It will just mean that all three matches won't be against the same nation in the years following the Rugby World Cup", he said.
France and England are also pencilled in to tour the Pacific Islands in this period, while Japan, Canada and the USA will host tours.
"(The schedule) sets new standards by prioritising rest periods, promoting equity for the sport's emerging powers and harmonising the relationship between the global and domestic games", World Rugby said in a statement.
Former Wales stand-off/full-back Jenkins toured as a Lions player in 1997, while ex-England loosehead Rowntree toured in 1997 and 2005.