Wales defence coach Shaun Edwards is to join the London Irish coaching staff after the Grand Slam winners\' summer tour to Australia.The Aviva Premiership club confirmed the former Wasps coach will join the coaching team following the news that Toby Booth, Justin Bishop and Neal Hatley are to leave the club.Edwards will continue in his role as Wales defence coach but will spend one day a week at the Aviva Premiership side as allowed under his contract, it was reported in the Guardian.