Drywalling the studio’s outer wall — using double 5/8" drywall and Green Glue

Part 21 — Designing and building a DIY home recording studio.

6 min readMay 20, 2019

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The whole story — part 1, part 2, part 3, part 4, part 5, part 6, part 7, part 8, part 9, part 10, part 11, part 12, part 13, part 14, part 15, part 16, part 17, part 18, part 19, part 20, part 21, part 22, part 23, part 24, part 25

Here we go!

With both the inside walls framed and the outer walls framed (for the room-in-room construction), and both electrical and insulation done on the outer walls, it’s time to drywall the outer walls. This will help move both the studio and the rest of the basement along at the same time.

If all goes well, this is what I’m building.

Putty Pads

Before I can drywall, I first need to seal up the back side of the electrical boxes. If left untreated, electrical boxes (even metal), are a real weak point for sound transferring between rooms. Putty pads really dense, but flexible clay pads that can layer if needed and are completely plyable. When wrapped around the back of the electrical boxes, they bulk up the box so sound can’t just push right through it. It also seals up the holes that the wires are running through — which are necessary to run wire, but are the biggest sound issue with these boxes.

These putty pads aren’t cheap, but they do the job! I bought mine on Amazon. At the time, they were $20 less per box when I bought them. They are made of clay. You know, like, from the Earth. I have no idea why they jumped up to $90 now. (?!)

There are several knock offs out there, but read the reviews before buying. I found a couple that looked good until reviews said they were actually quite flammable — as opposed to fire retardant like this brand.

This is a small, but heavy little box!

Here is a picture just before we insulated the exterior studio wall and began drywall. We are finishing the rest of the basement at the same time, so there are lots of things happening almost simultaneously.

The electrical boxes are sticking way away from the wall so by the time the 2nd 5/8" layer is up, it will be slightly recessed like it would using normal 1/2" drywall in standard construction. Even though I was totally focusing on the placement, I still forgot to account for double wall on a couple of them and had to move them further out at the last minute

My father-in-law is being very patient with all the extra craziness and work required with installing double perpendicular drywall layers and using Green Glue between in between. Having a little fun with my Green Glue patterns this time. As long as I have 2 speedload of Green Glue on the sheet fairly evenly distributed I’m good.

Some of the best advice for working with Green Glue is to leave approx 3" of border around the edge of the sheet — so I’m not grabbing Green Glue when I grab the sheet edge. This glue really is an amazing substance. Almost odorless, completely workable, but keeps it’s shape and doesn’t run down the sheet when we tip the drywall up.

If you need to scrape it off the side of the bucket or the sheet itself, simply use a silicone spatula. It works fantastically well. Also, if you want to wear gloves so you don’t get this stuff on your skin (I highly recommend wearing gloves!), the gloves that are dipped in the blue rubber material work really well and the Green Glue wipes right off of them.

The outer layer is laid perpendicular to the first layer. As you can see, this covers up the seams of the first layer really nicely. Then I will still caulk (with acoustic caulk ), all the borders and edges etc of the second layer.

The double exterior drywall layers with Green Glue are up!! Now back to the inside of the studio.

Sealing the gaps with acoustic caulk

More on this later, but suffice it to say that every gap around every board of every wall and seam has to be closed. Using acoustic caulk is the way to go when possible because it remains flexible once it dries and it can flex when the walls move. If caulk cracks, then it’s no longer air tight, which means sound pressure can push its way through.

In order for the drywall to pass over the electrical junction box, I had to cut it so it was large enough to pass over the little parts that protrude from the sides and top/bottom of the box. It’s annoying, because I wanted the drywall to almost be pressure-fitted around the box, but the box just has too many little weird things. Oh, well. I guess that’s why we have acoustic caulk for here too. PLUS the putty pads sealing things up on the back side of it. We are all good. I just don’t want any gap or crack that isn’t absolutely necessary — If I can help it/prevent it.