I'm moving into a sharehouse and I'm worried my portable aircon is going to be unbearably loud for my flatmates. I don't share a wall with anyone but there is another room across the hall. Is there any way I can dampen the noise of the portable aircon for people outside the room?
Welcome to the Bunnings Workshop community @itsangus. It's fantastic to have you join us and many thanks for your question.
Sound can transfer through structures and the air. Vibrations are the form in which sound transfers and reducing them will minimise the noise. Initially, I would start with trying to isolate the machine itself from vibrating through the floor. Placing anti-vibration pads underneath it will help. You can try to stop the sound transferring through the air by hanging a thick woollen curtain or blanket over your door frame.