How to Soundproof a Ceiling
Hi, If you’re looking for information on ceiling soundproofing you came to the right place, my name is Ned Shatzer, I’m the owner of Hush in New York City. Soundproofing is a combination of multiple noise reduction techniques. We attack sound from every angle possible for a combined overall reduction. My goal for this video is to give you a solid understanding for what an impact noise treatment should look like, we also encourage other contractors to use our techniques, if you’d like to hire us for a consultation, please contact us here firstname.lastname@example.org, we will come to your location, take an onsite reading, provide you with the suggested treatment, a full list of materials and a quote for the job.
It’s important to understand that frequencies under 80hz are very difficult to eliminate. We may only see a 20+% reduction in this range. However, these frequencies are not affecting us the most. Humans are naturally triggered by higher midrange frequencies between 300hz to 4khz, banging, yelling, babies crying, we’re supposed to respond to these frequencies for a reason, this is how we survive. However, when we’re trying to relax and these uncontrollable noises are happening around us, it creates anxiety, loss of sleep, higher blood pressure, higher cortisol levels and lower dopamine which we know leads to depression... The good news is within this particular frequency range, we can see a 70+% reduction with the treatment I’m about to show you. To the human ear, this would be considered inaudible in most cases. As you can see the higher the frequency, the greater the reduction.
What I’m about to share with you is a heavy STC 75+ treatment, It uses a combination of 14 layers of materials, we’ve used this treatment many many times, we know it works and all of our clients have been very happy with the results.
During the job, there will be a lot of dust in the air, we ask that you find a place to stay for the duration of the project and make sure all of your valuable items be moved, covered and stored in a safe place.
The first thing we do when we enter your home is cover the floors with ram board and apply wall coverings around the perimeter of all the rooms. We then kindly remove your ceiling and dispose of all debris.
We search for any weak points that sound can resonate or travel through such as HVAC ducts, pipes and electrical, we seal all gaps and cracks with acoustic caulk and or spray foam, we then wrap the ducts with foil-back self-adhesive neoprene or Mass Loaded Vinyl. All electrical boxes and recessed lights get covered with quiet putty clay sheets which help reduce noise transfer through metal. So we basically make your ceiling virtually air tight before we even start.
We then install 2 layers of Sheetrock with mass loaded vinyl against your upstairs neighbors subfloor between the joist. This strengthens the floor and weakens sound on impact. It also reduces the sound pressure from the air being pushed every time someone walks above you. By throwing Mass loaded Vinyl in the mix we also damp vibration and block additional airborne noise such as floor creeks, loud television and talking. I like to think of this part of the process as a drum or Conga, if you put your hand on top of the Conga and apply pressure then hit it, it doesn’t make as much sound, and that’s exactly what’s happening when we apply the extra mass directly to the subfloor, the number one way to reduce sound transfer is Mass, meaning sheetrock, mass loaded vinyl, concrete, wood, dense materials and lots of it.
Next, we install 3 layers of mineral wool insulation. 2 layers of Sound Proof Insulation (Rockwool SafenSound) and 1 layer of Rockwool Comfortboard. Comfortboard is a more densely compressed insulation board made from the same material, the combination of the two insulation densities reduce different frequencies within the cavity.
So Without insulation we have sound reflecting within the cavity that amplifies and resonates, very much like when you hit the Conga. If I were to fill the Conga with a blanket it would muffle the sound significantly. Same with the ceiling. So Insulation doesn’t necessarily stop sound but it weakens sound energy and reduces the amplified reflection within the cavity. That’s why it’s important that it’s installed correctly and we don’t leave any gaps.
Let’s talk about decoupling, Right now the Sheetrock on your ceiling is attached directly to the joists that run the entire length of your ceiling, if someone were to drop something on the other side of the room, that impact vibration is going to travel across the entire ceiling soundproofing and can be easily heard as if it happened right over you head. With decoupling we attach hat channel to resilient isolation clips, now vibration can only travel through a single screw every 32 inches instead of the entire ceiling. I like the A237R clips from resilmount, if you buy a box of 100 they get cheaper. Also make sure you use 25 gauge hat channel, you won’t be able to squeeze 20 gauge into the clips.
We then install 2 layers of Sheetrock with either Green Glue or Mass Loaded Vinyl in between. Green Glue and mass loaded vinyl both have vibration damping properties. I prefer Mass Loaded Vinyl to Green Glue, however Installing MLV is a bit more labor intensive with higher materials cost, it also performs 10x better than Green Glue, so in some severe cases, it’s very necessary. Finally we encase the treatment with a level 5 skim coat, skim coating is an additional layer of joint compound over the entire ceiling which adds more mass to the ceiling, mass is the best way to reduce noise transfer, so we can’t get enough of it. All soundproofing treatments are delivered complete with painting and finishing.
In the end, there is absolutely no cutting corners in New York soundproofing. Theres a lot of products and gimmicks and misinformation. Please talk to a professional before wasting your valuable time and money. I hope this video gives you a bit more insight into ceiling soundproofing, feel free to ask questions in the comments. And if you learned something from this video, click like and subscribe.
Sound Proof Insulation for Ceiling Soundproofing