
The new building, which will house a fully-equipped gym and indoor training facility, will be the first of its kind for the club.
It was made possible by club fundraising, including a charity ball which raised more than £26,000 in November last year.
The new building will be 135 square meters and work will begin in the Spring with completion due by next rugby season.
The project will be overseen by Mr Dan Boddy who was also the project manager for the original Kilnwick Road development.