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Author Topic: I want to build plugs to reduce 8 lane highway noise, where and what materials  (Read 11676 times)


  • Guest

I want to build window plugs to reduce 8 lane highway noise, where to buy and what materials would be best please?

Two windows in my bedroom, wish they would not have build any windows in the master bedroom with this eight lane Interstate about 200 feet past my back yard.  However, I don't care if they are covered up completely, but after reading a lot, sounds like plugs for each window may be best value and effectiveness?

Each window is around 35" x 58 1/2" inside the frame.

Any other advice is more than welcome, thanks.

Would it be best to board these two windows up with half inch fiber board on the inside covering and caulking it, rather than build plugs - or, get the inside second windows and install, there is 3" of air space between the windows and edge of inside window frame/wall.

Goal is to be able to sleep with all these big tracker trailer rigs running north and south all night long, so reduce the lower frequencies as mush as possible is what I believe I need to do.

Thank you for your help.

Randy S

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Randy Sieg

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  • Guest

Basicly, buy a super soundproofing mat from supersoundproofing... yes, i suppose that would work, but if youre willing to plug your window, im guessing you dont have the money for stuff like a soundproof window, or an expensive soundproofing mat.  This is what i know: if your walls do a good job blocking the sound, then try to mimic their construction. That is, mass air mass, for example.  The air gap helps with higher frequencies, but not the lower ones; that where the mass comes in.  Use something heavy like MDF (though it can get moisture damaged easily). Personaly, i used a 1/2 inch cement board, though im wandering if i should have used 5/8 inch MDF instead, as a solid thick layer is better for low frequency.  You can pretty it up by installing some little shelving on to put stuff on; you may also attach doors on hinges to cover over the shelves as even better soundproofing.  One final note is that soft, yet dense materials seem to help with all frequencies (hence, the soundproofing mat).  Bitumen is another alternative, considering that you dont have the money for a sheet of solid lead either.


  • Guest

I'm having A issue, with A room on the back of my  house located in central Florida. There is a semi busy 4 lane highway 2 blocks from my home, and A neighbor behind my house who owns A rumbling pickup truck. I am also next to a 2 square block park that attracts the occasional teenager with loud subs in their car. I realize there is not much I can do cheaply about the teenagers, but I am trying to find A cheap solution for the traffic noise. I want to permanently plug the two double 3'x6' windows in my back room. My 1 story house is made with cinder blocks but the additional back room is just wood framed with I am assuming A plywood exterior , and drywall on  the interior.I also have aluminium crank out windows from the 70's. I have caulked the windows well, and I saw an improvement.

 Question... I have practically no budget. How well would 2-3 layers of 5/8 drywall work ,pressed against each window, sealed and caulked , with some framing on the room side, to hold it in place in the window well? A professional acoustical consultant suggested this on another forum. In addition he said to fill the space between the framing with absorbent. I don't quite understand what he meant by that last part, maybe someone here can help me with it?

The room is small , about 9'x15' and may consider A couple more layers of drywall over the walls in the future, but for now I am concerned with the windows.


  • Guest

If you're going to do that, make sure that the framing is 'between' the window and the drywall to create as large of an airgap as you can.  The low frequency resonating point begins to form even with the slight gap that would exist even if you just laid the drywall directly against the window glass; in other words, you might as well just make the gap as large as you can.  Speaking of which, how deep is the wall cavity?  Also, I'm guessing by "absorbent", he just means to say an absorbent material, such as fluffy fiberglass insulation.  For the future, there are two main things that will help with low frequency aside from a solid foot of airgap:  mass and structural decoupling.  Alone, each of these two is limited in effectiveness, but together they are exponentially better.


  • Guest

I believe the wall cavity is 3.75 inches.The aluminum frame around the  window accounts for about 1.25 inches of that, but from the glass in my window to the edge of the cavity , its about 3.75 inches. If I use 2 layers of 5/8 Drywall I think I could get a air gap roughly 2.5 inches. That would mean that drywall would be flush with the rest of my wall. I hope I explained that well. I would just need A way to secure it properly, maybe just molding? I am not much of A carpenter.


  • Guest

You really need as much air space as you can possibly allow for, and two and a half inches is not much.  If you're wanting these windows permanently pluged, does this mean that you are wanting or willing to eventually remove the windows and replace with siding sometime in the future?  If so, you might just cut the drywall pieces over-sized and temporarily screw the two layers in place directly over the top of your current drywall, that way you can achieve at least the same airgap as what is in your wall cavities.  Later after removing the windows, you can redo the plug so that it sits flush with your drywall.

If you're not going to replace your windows, but are going to eventually add more layers to your wall, just frame the plug into the window as you were going to, but make the framing flush with the framing of your wall; that way when you redo the wall, you'll be able to easily make the whole wall flush.  If you're going to tear out the wall and add staggered studs, just do the temp job I mentioned in the first paragraph.

If you're not going to replace the windows or fix the walls, I would again make the airgap in these window cavities the same depth as your wall cavities by attaching the plug to the top of the current drywall; just frame around it with trim or something so that it looks more professional.  Maybe hang some paintings on the plugs.   


  • Guest

I think I will do as you say and attach the plug over my current drywall and see how much that helps.I might get lucky and be satisfied with the results.Adding  drywall to my walls is something I would not look forward to.I believe I could get some nice quilts and hang them on my walls also, that might help.
So, I believe I  would just have to make sure the plugs are caulked well, and that they could be attached securley.I think they may have framed the window cavity with 2x4's. I will have to get my stud finder and check. That would help hold them. How much larger than the window cavity should I make the plugs?
By the way, I appreciate your advise, you have been very kind and helpfull.