Leak Barrier as soundproofing

[Mike Olson]

Has anyone tried to use the self stick roofing leak barrier for sound proofing?

It seems similar to the stupidly expensive stuff that they sell for car stereos. My shop is in the basement and all the noise i make goes right up through the heating vents.

I'm thinking about picking up a roll of the GAF StormGuard from HD and wrap the outside of the heat ducts in the basement to keep from waking up my 2 year old.

Mostly i'm concerned that it might off-gas some stinky tar smell. I'm sure it will withstand the heat and cold since it's made for roofs.

Thoughts anyone?
Thanks

[Mitchell Andrus]

I'm thinking that the adhesive will disappoint you in a short time.

Google soundproofing matting and see if there isn't something better. 1/2" to 3/4" plywood would prolly work much better. Can you box the joists and cover the rest with ply and use canned foam for the gaps? (without screwing into the duct, a code violation)
.

[Matt Meiser]

We used to use it in cars, on the floorboards and such to dampen sound like the commercial stuff. My dad bought a whole roll. But there we weren't relying on the adhesive to permanently hold it in place plus the summer heat baked it on to some extent. IIRC, a heat gun would make it stick better, but too much made a stinky mess. Probably depends on the brand to some extent. Some is really rubbery and smooth, some is stiffer and has some texture like the stuff they just used on my roof. The latter is probably a lot safer to walk on.

[Dennis McGarry]

I doubt it will work well at all. It will still transfer the sound waves right up.


best best construct a room within a room, stager the studs, and Do not attach it to any structure that is there. make sure to block off any runs that go stright up with a fire block. Use cheap 2x4s and 1/2 ply wood and you will have a very quiet house and loud basement...

[Greg Portland]

Mike, soundproofing uses a variety of products. Some are dampeners (typically by adding mass or making the object stiffer) and others are absorbers (lowers the transmission of sound). Optimal soundproofing uses a mix of both and is engineered for the specific space. Although mass-loading your ductwork with tar product may reduce vibration transmission, you'll still need absorption product around the duct area. Also, I think the tar paper is going to melt off the duct... it doesn't take much temperature for the stuff to turn to goo (at least that's what happens with the acoustic dampener product).

I would look at acoustic batting or acoustic fiberglass panels. Owens Corning sells a variety of products specifically designed for duct work. Alternatively you can buy some rigid fiberglass acoustic panels or batting and line / wrap the duct. Definitely e-mail Owens-Corning, they are usually happy to discuss your problem and how to solve it (with their products of course :-) ).

[Jim O'Dell]

I doubt that the ice barrier used on houses would do much for sound. Built for 2 different things. Dynamat is expensive, but seems to work very well. It converts sound into heat, from what I've been told, and dissipates it that way. Jim.

[Bruce Seidner]

I doubt it will work well at all. It will still transfer the sound waves right up.


best best construct a room within a room,..

We have needed to sound proof offices and this is the only thing that works. The failures occur at doors unless they are fitted well. But if the problem is sound going up then McGarry is spot on in my experience. Exotic materials are pretty useless. It is all about decoupling the spaces.

[Mike Olson]

looking for another of my posts, i came across this one and thought I would give an update.

I ended up using some 6" wide asphalt self stick aluminum backed patch material from Home Depot. I was a little concerned because if you poke your finger through the wrapper and sniff the package it's pretty stinky.

Turns out, the foil backing traps all the smell. The next day the smell was gone from the room.

I applied it to my heat ducts and wrapped all edges with foil tape to better secure it to the ducts and also to trap in any smells. It did a FANTASTIC job at blocking out the sounds. I have sawn, planed, used bench chisels with my hammer and have not woken up my daughter. I also had my 6 year old son stand in her room and make lots of noise and I could barely hear him from my shop. I used to be able to hear my daughter coughing and tossing and turning in her bed.

It also has held up well to being chilled with AC and heated on the cold December days. I also covered much of the ducts running through the closets.

[Jarrett Vibert]

FWIW...

The best solution would have been to replace the metal duct work with a flexible type. The Borg and the like sell a 25' length for ~$50, but it can be had at < half that cost if you can find a commerical HVAC wholesaler who sells to the public. Most types have an inner ploy sleeve but the best type for sound control has a doped material like canvas.

The best way to control the transmission of sound through ducts is to use material that doesn't transmit vibration and use bends within the run so the vibrating air loses energy by colliding into corners.