I don't really know what size mine is. It's a pretty good size room, and I have also have a very large closet and half the laundry room for storage. It's still not enough. LOL Don't forget you will also need space for ironing, a design board, a cutting table and storage for your stash, etc. A long arm setup will take a lot of space. Make it bigger than you expect to need - you won't be sorry. Have fun planning and dreaming.