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Noisy Furnace, Ducts, Pipes
Problem: Noise stemming from air or liquid flow transmitting through the walls of your pipes and ductwork hidden within your walls. Also, noise from the furnace or mechanical room emanating through common walls throughout the house.
Solution: Wrap the pipes and ductwork with an acoustical jacket. Hold the noise to within the walls of the pipes or ductwork.
A common problem, especially for bathroom/kitchen/plumbing and furnace/AC sources in your home.
Let's start with those lucky few who have access to their pipes and ductwork. Your job is simple. Get our NetLag Ductwrap and jacket around the pipes or ductwork. Your done! This material is ideal for the home do-it-yourself type project. Available in 4'x30' rolls. Check our link to NetLag and call us for questions. You simply cut this material to fit around your noise source, and tape it shut like a golf glove. Typically 15-20 dB drops are realized. Every 3 dB drop is a 50% drop in sound pressure.
As for the noise spilling out your supply vents, there is less you can do to effectively "block" that from hapening. If you have access to your ductwork, we suggest you consider bringing an HVAC contractor onsite, have him cut a straight piece of ductwork out of your system, and replace it with a coiled section. This would force the noise to have to "bend" through an "S" shaped duct as the airflow remains uninterrupted. Then wrap the "S" with our NetLag material. Some customers open their supply vents and apply our FireFlex to the inner walls of as much duct as they are able to treat. This foam panel is fire rated, and will absorb some of the echo. Not the best answer here, but maybe better than doing nothing.
Beyond treating these targeted noise sources, you may also opt to sandwich a layer of dB-Bloc onto your walls prior to a finished layer of drywall to help reinforce your overall effect. Remember, the more weight and dead air space you layer into your common wall, the better your result. For any furnace/mechanical/pump room noise transmitting through your walls, this dB-Bloc is ideal if you plan to frame around this room and drywall it up. You could also opt to simply call us and feed us the dimensional size of your common walls within this room, and we can cut a series of QBS-1 Blankets for you to free hang from the top of your walls within this room. These blankets contain the dB-Bloc barrier and serve as an excellent, portable solution to your noise problem with no need for finishing off the wall.
Now let's address the issue most callers have. What if the walls are already finished off and you can hear the liquid flow, air flow through the pipes or vents within your walls?
You could opt to take the drywall off, follow the procedures we just outlined, and refinish your walls. If this is not a viable option, your best bet is to follow the advice listed under the Stop Noise Bleed Through Common Wall section. Here we outline the use of our dB-Bloc barrier material when applied to an existing finished wall. Staple the material up, line the walls with horizontal firring strips, and then apply a second layer of drywall. This density + disconnection technique will help hold your pipe/duct noise to within your walls.
If you're adverse to doing that, sorry. We can't solve every problem. At this point, you might best be served calling an acoustical consultant out of your yellow pages. Good luck!
http://www.controlnoise.com/noisy_pipes.html