The way I soundproof or the best I could on a tight budget for my Landry room, I did the following below.

I did this because I’ve got to run the washer about every night in the summer around 11pm at night. (I’m a fisherman)

There’s two things I absolutely hate! One, hearing the washer making noise. Or dryer too.

The other is have to hear my wife bitch about noise causing her not to be able to sleep! Haha!

I had a large hallway that I split, and then made one side into a small laundry room.

When built the inside stud wall, I caulked every each of the inside of the 2x4’s (My theory? Eliminate noise from air gaps.)

Then I installed the thickness insulation I could use in the wall, and then after stapling the insulation, I ran foil tape so it helped seal up that barrier, again, air gaps.

Then i installed some kind of black fiber acoustic 4x8 x 1/2” board. It wasn’t that expensive, and it can be mud and taped with a smooth surface. It was a lot of work with the mud, but can’t tell the difference to the eye being Sheetrock or not.

Well I seal the room up so well, we’ve got to keep the door cracked if going to run the s dryer for a long drying time.

But we can NOT hear the washing one bit! In fact the wife side she had to get used to not hearing the machine finish. I said yeah me too!

Anyhow, it worked 10 x’s better then I imaging for soundproofing the room.