Insulating a finished apartment wall

[varner.s48716]

Hey guys!! Just moved into an old apartment and I'm hoping to get some advice on insulating the perimeter walls. They're already finished, framed, and drywalled, but they're completely uninsulated. It is causing a major noise issue and I have no idea how the previous owners handled it. The framing is about 10 inches from the foundation wall. My main goal is to dampen some of the noise from plumbing pipes and electrical fans that are super loud.

I was thinking of cutting a horizontal strip out of the drywall and trying to stuff rolled insulation in from the side. It sounds pretty awkward and I'm not sure how effective it would be, but it's the only idea I've got without tearing everything down. Is there a better or more efficient way to insulate an already-finished wall like this?

Also, there's a section of wall that's right next to the bathroom, and the sound of the fans and water pipes is a nightmare!! The foundation wall juts out a bit there, making for a tight space. Could I use something other than rolled insulation, like rigid foam panels, to get better sound dampening in that spot? Or does that area need to stay open for airflow? Any advice would be a huge help. Thanks in advance!!

 

[Quietwall]

Your idea of making a horizontal cut probably isn't the best choice, insulation has to fill the cavity all the way. A couple of better options would be to drill holes and blow in some cellulose insulation, or you could remove sections of drywall and insulate them properly. If you're looking to dampen sound, rockwool is a great option since it's more effective than fiberglass for noise reduction. Just keep in mind that rigid foam isn't going to do much for sound. Also, make sure to see if that cramped bathroom area needs ventilation before sealing it off.

 

[furg0y]

Just go blown in insulation, it usually is the easiest cos you can drill small holes and fill the cavities without tearing drywall. For the tight bathroom section, rigid foam won't help much with sound; acoustic panels or spray foam might work better, but make sure you don't block needed airflow

 

[cordur0y]

I'd skip trying to stuff batts from the side it's messy and usually doesn't fill evenly and everyone has made mention of blown in

 

[RFelton]

Hey guys!! Just moved into an old apartment and I'm hoping to get some advice on insulating the perimeter walls. They're already finished, framed, and drywalled, but they're completely uninsulated. It is causing a major noise issue and I have no idea how the previous owners handled it. The framing is about 10 inches from the foundation wall. My main goal is to dampen some of the noise from plumbing pipes and electrical fans that are super loud.

I was thinking of cutting a horizontal strip out of the drywall and trying to stuff rolled insulation in from the side. It sounds pretty awkward and I'm not sure how effective it would be, but it's the only idea I've got without tearing everything down. Is there a better or more efficient way to insulate an already-finished wall like this?

Also, there's a section of wall that's right next to the bathroom, and the sound of the fans and water pipes is a nightmare!! The foundation wall juts out a bit there, making for a tight space. Could I use something other than rolled insulation, like rigid foam panels, to get better sound dampening in that spot? Or does that area need to stay open for airflow? Any advice would be a huge help. Thanks in advance!!

Install MLV right onto the drywall, then cover it with acoustic panels or fabric. This adds some weight to block noise from getting through without tearing everything apart. It's great for blocking sounds from pipes or fans, maybe even better if you stack it up.

 

[warhols54]

I had the same problem in my old place. Those thin walls and loud pipes made it hard to sleep. Have you tried using soundproof caulk or pads around outlets? That helped a lot in my case.

 

[Tir_McDohl]

If I were you, I'd skip rigid foam behind drywall (that's tough to do cleanly) and instead go with isolating clips + new drywall + damping compound (Green Glue style). That gives added mass and decouples the new layer so vibration doesn't pass straight through the old wall.