The Mountaineers first added another weapon on the offensive side of the ball when Johnson, a tall and rangy tight end, committed on Tuesday morning.
Johnson made the decision while at his school, and informed BlueGoldNews.com of his choice soon afterward.
Johnson had an outstanding visit to WVU last weekend, and left impressed with everything he saw on campus.
Joseph is a three-star safety, rated as the #37 player in the country at his position. Johnson is also a three-star prospect, and is rated as the #38 tight end in the nation.
The commitments bring West Virginia's known list of verbals to 27. Several of those players are anticipating early enrollment this January, including quarterback Ford Childress.