Soundproofing Ceilings

On average, noise coming through a ceiling is the worst soundproofing problem you’re likely to encounter. The reason is two-fold. First, the hard flooring choices of today don’t help the noise control problem at all. Carpet and pad used to reduce a lot of the noise. Hardwood, linoleum and tile are not the friends of the neighbor below. Second, a footfall introduces a great deal of energy into a very small cross section of floor. This can overwhelm many common soundproofing efforts.

Here’s what you’re up against.

Imagine your neighbor’s footstep hitting the floor above. This large amount of vibration will race through the flooring above and start entering your ceiling framing. The framing is VERY conductive, so vibration passes through very easily. Your ceiling drywall is rigidly attached to this vibrating framing, so a millisecond after the footstep slams the floor, the vibration enters your ceiling drywall and then hits you.

Another problem with vibration entering the ceiling framing is that your walls downstairs are holding up his framing. So his sound is also entering your room through your walls. This is known as flanking noise. Not as much sound will come through the walls, however perhaps 5% to 30% of the noise you’re hearing may be coming in through your walls in stereo.

Lastly, there are generally holes in your ceiling for lights, ceiling fans and ventilation. There are also possible flanking paths that need to be dealt with.

Do I treat the noise from the floor or the ceiling?

When designing any soundproofing solution, we would always prefer to treat the noise at its source. This allows us to control and reduce the (sound) vibration before it enters the building’s framing. If the vibration enters the framing, the very conductive framing materials can carry that vibration a great distance.

If we could treat the floor above to immediately destroy the vibration before it gets into your ceiling framing, things would be a lot easier. With a hard finished floor above, however, this is generally not possible, and he probably doesn’t want to help you anyway. So really all you can do is treat the ceiling on your side.

How to soundproof a ceiling?

There are three levels of isolation that you can consider:

Soundproof Solution 1 - Add double drywall and Green Glue to your existing ceiling

This level of isolation suggests adding two additional layers of 5/8” drywall to the existing drywall or plaster. This make the ceiling more massive and utilizes standard $8 drywall. Install a medium coverage of Green Glue between the layers. This will damp a great deal of the vibration, but not all, since the vibration is racing through the framing above the new drywall layers, with some of this energy entering your walls.

This method adds Mass and Damping, two of the 4 Elements of Soundproofing.

Ease and Cost	Performance
Inexpensive Simple Fast The only issue is accurately finding the existing joists	Customers select this Level about half the time. Results are quite effective. Impact noise is reduced. Airborne noise is reduced.

Soundproof Solution 2 - Remove original ceiling and add Drywall and Green Glue to the subfloor

Remove your existing ceiling drywall or plaster & lathe and treat the floor from the underside. This is a distinct departure from Level 1, since we now are able to directly address the vibration at its source and treat the underside of the subfloor.

You may need to trim any exposed nails that may have been used to attach hardwood flooring above. You can rent a long handled nail clipper or use a hand held grinder. There is no need to trim them totally flush with the ceiling. Leaving ½” of the nail exposed is fine.

Add one layer of 5/8” drywall and one layer of Green Glue to the underside of his flooring and secure with screws as shown. Don’t worry; simply select the correct screw size and there’s no possibility of the screws penetrating his floor. If you have shortened nails still exposed, simply tap the drywall on place with a rubber mallet. The short nails will.

This will effectively arrest a good deal of that vibration before too much gets into the framing. Then add standard R19 fiberglass for Absorption (nothing thicker or expensive).

Add two layers of drywall and Green Glue to the joists.

This method adds Mass, Damping and Absorption, three of the 4 Elements of Soundproofing.

Ease and Cost	Performance
Moderate expense Simple More preparation is required to allow removal of old ceiling No loss of ceiling height	Customers select this Level about 10% of the time. Results are broader and more effective than Level 1 Impact noise is greatly reduced. Airborne noise is also reduced.

Soundproof Solution 3 - Remove original Ceiling and add Drywall and Resilient Clips

Solution 3 provides the best and most definitive soundproofing. Remove your existing ceiling and add two layers of 5/8” drywall to the underside of the subfloor above. The added mass and double damping is almost as effective as adding a rubber isolation pad to the top of his floor. This very effectively reduces the amount of vibration racing through the floor toward your walls.

As with Solution 2, you may need to trim any exposed nails that may have been used to attach hardwood flooring above.

Install R19 fiberglass for Absorption.

Install Resilient Sound Isolation Clips and metal Drywall Furring Channel to the underside of the joists. This is a significant aspect of Level 3 since it effectively decouples vibration in the joists from the drywall.

Then add two layers of 5/8” drywall and two layers of Green Glue to the Drywall Furring Channel. All screws are secured to the Furring Channel, not the original joists.

Solution 3 provides all 4 Elements of Soundproofing. Decoupling, Absorption, Mass and Damping.

Ease and Cost	Performance
Most expense Simple More preparation is required to allow removal of old ceiling Only 2 ¼” of ceiling height lost	Customers select this Level about 40% of the time. Results are broader and more effective than Level 1 or Level 2 Impact noise is dramatically reduced if not completely eliminated. Airborne noise is likely non-existent

Who Should Install These Systems?

In any of these soundproofing scenarios, the best tradesperson to look for is a drywall contractor. The most difficult aspect of these sound isolation solutions is the finishing of the drywall.

Have a Concrete Slab for a Ceiling?

A single layer of concrete poses a unique challenge for sound isolation. The ceiling is already massive, and adding more mass alone won’t help you. The only real choice is to:

• Introduce an air cavity
• Insulate the air cavity

Decouple the new drywall ceiling from the old slab ceiling with Resilient Sound Isolation Clips and Drywall Furring Channel

Add double drywall to the Drywall Furring Channel and one layer of Green Glue.

The deeper the air cavity, the greater the sound isolation. A 3” air cavity is a minimum. There are various methods of securing this ceiling to the slab above. To help we suggest you give us a call. 800-397-8791

Phone: (800) 397-8791 | 2520 Schuette Drive Midland, MI 48642 | Back to Top
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