The 25-year-old arrives as injury cover for David Paice who is out with a fractured radius.
Kevin is a former Stirling County player who has represented Scotland at U18 and U19 level.
He's a former winner of the John Macphail Scholarship, which earned him a summer playing Club rugby in New Zealand.
London Irish Director of Rugby, Brian Smith said: “Kevin is a very promising young hooker. He’s providing cover for David Paice who is still a month away from playing. Gregor Townsend has kindly loaned Kevin to us, he’s a tough lad with a good all round game. I’m sure he’ll do well while he is with us.”