for the extent of work you plan on having done, you are surely consulting a architect for a set of remodeling blueprints with your desired changes. for the game room area ,,the architect would have to gain the services of a certified structural engineer to verify what would be acceptable with both their certication stamps put on the drawings. Then you would need to take those drswings to your citys permit department or your general contractor would do this for you to get the necessary building permits for the job to comence. and as Henry noted city inspectors will have to inspect the job along the way and approve continuance to verify things are being done to code. good luck LJ