The Sauna is a room with a wooden door (possibly oak), a plank on the left side of the door, the switch on the right side of the door and a diamond shaped hole on the door.
To lure Granny in, the player must drop an object like a vase, Hammer, keys, etc. in there and hide in the Cabinet or Car. When Granny goes in, the Player can close the door and lock her in by barring it off.
Once she has been inside for 15 seconds with the steam turned on, she will be knocked out for the same duration as being shot with a Tranquilizer Dart. However, if she stands at the door for 20 seconds without being knocked out, she will break the plank off of its hinges and open the door, permanently rendering the trap useless until next game.
- The Sauna is one of the four ways the Player can knock Granny out.
- It is strange that Granny would build the Sauna at the Garage.
- It is possible to lock yourself in if you stand in the doorway, close the door and lock it with the plank, then walk inside. Take note that you can't suffocate from the steam, and the trigger allowing Granny to break open the door is only on the inside of the door, meaning you are permanently stuck inside unless you restart the game.
- This is not always the case as of the 1.5 update. It is now possible to bring a Gasoline Can and loaded Shotgun into the sauna before performing the glitch. This allows you an easy out by detonating the can while standing near it, respawning you in the Starting Bedroom at usual. Keep in mind this can only be done once, as the Gasoline Can will not reappear. You only get one chance, and if you miss it, it's gone.
- There is a trick you can perform by throwing an object inside of the sauna, hiding and then locking her in. When she is about to get knocked out, there is a glitch if you die then, Granny will become frozen on the respawning spot. This can be extremely useful except on Day 1, due to the fact the bedroom door is locked on Day 2.