Some additional information which I have obtained from:
"Isle of Man 20th Century Military Archaeology - Part 3" published by the Manx Heritage Foundation 2006
These barracks comprised the Army Guard Site for RAF Scarlett, not the accomodation for the RAF staff.
The small building by the entrance gate is the Armoury. The other building is a combined barracks / cook house. The internal arrangement is believed to have included, canteen area, toilets, the barrack room itself and an NCO's bed room.
John