How many windows are in the wall facing the road? Do you plan to make any window changes?

Bruce

If the wall is already insulated, I doubt those changes will make much of a difference. Most of your sound will be coming through any windows.

Thanks for the replies. I have one window facing the road. I am not sure how well insulated the wall is. The house was built in 1978 with aluminum siding on the 2nd floor and brick on the 1st floor. The first floor is much quieter than the upper and it has 2 patio doorwalls and 1 window versus 1 window in the upstairs bedroom where I sleep. I was thinking that since the lower level is so much quieter that the brick vs aluminum was making the main difference.

I will check into a local acoustical engineer. I am hoping to make an improvement with the siding and potential underlayment of some type and then tackle other factors like the windows. I just don't want to miss an opportunity to do something with the walls under the siding when the siding goes up. Thanks!

You are correct that the brick will do more to block noise than any kind of aluminum or vinyl siding. Can you brick up the rest of the wall?

Bricking the rest of the wall would be much more costly and wouldn't look very goo on the style of house I have. I am hoping to find something can can under the new siding that will help dampen the noise.

Just thinking out loud here, I wonder if you could use mass loaded vinyl (MLV) behind the siding. Normally it's used between the studs and drywall. Again, a good acoustical engineer would probably have some ideas.

I'm no expert on acoustics, so take my advice with a grain of salt.

You could throw a lot of money at this without much result. Go for simple, obvious fixes. If the window is single pane, replace it with a double pane or install a storm window over it. A layer of soundproof drywall on the interior would probably be cheaper and help more than any type of exterior siding.

Hi, Dave,

Another option you might consider is the use of landscaping to mitigate noise. I don't have expertise in that area, but wanted to put it on your radar.

Thanks again for the helpful ideas. I am going to get siding anyway so want to do what I can underneath the siding to dampen noise while I have the chance. A rep at Certainteed told me today that he put 1" thick rigid foam underneath his siding and it greatly reduced the sound from outside. I am going to look into this but if anyone has thoughts it will be appreciated!

Foam will have minimal effect as a noise blocker. It's too light. You need the exact opposite, something dense.

I'm not an expert, but I've worked in places where noise control was a Big Deal, and have watched soundproof studios being built. As I suggested above, I think you might be able to use mass loaded vinyl alone to get some noise blocking.

I would use it under the siding, where you'd otherwise apply foam board. It works best when it can move at least a little; normally it's stapled to studs before drywall is put up. I would try either 1 lb. or 2 lb. MLV. The higher mass version will have more blocking effect at low frequencies.

It's critical to caulk and tape every seam in the MLV.

If you can't do real non-parallel sound reduction windows, at least use double glazing. And make sure all gaps are caulked, both indoors and outdoors. This includes gaps around interior wall penetrations.

But as I say, I'm not an expert, and in your situation there may be a better solution. That's what you need an acoustical engineer for. If you're serious about soundproofing, it's probably worth it to pay for a consultation.

Good luck. Let us know how it goes.

Thanks for the suggestion about mass loaded vinyl and I will check it out. Also, will try to contact a local acoustical engineer and pay attention to windows and sealing the seams if I end up going that route.

I found the following soundproofing insulated board at home depot's website https://www.homedepot.com/p/SilveRboard-24-in-x-1-in-x-48-in-R5-Radiant-Acoustic-Insulation-Kit-STC-19-5-Piece-SB12AKIT/205975329 It looks like it has an stc rating of 19 if I am understanding the literature correctly. Maybe can use this with the mass loaded vinyl?

I'm not familiar with that material. Maybe one or both faces have some extra mass? If the STC rating is accurate, it will certainly help. 1 lb MLV has an STC of 26-27, and 2 lb. MLV's is 32-34. I don't know whether STC figure add directly, when they're used in combination but putting that over MLV should give you significantly reduced noise transmission through the walls. Get your windows and doors under control too, and you should have a nice improvement.

I still suggest consulting an acoustical engineer.

I’m not an acoustical engineer, but have been researching this topic for years, and have begun implementing some techniques to my complete home remodel.

The most important step is closing all air gaps. Adding MLV that is properly taped and caulked at all seams will take care of the outside. If you have a layer of plywood sheathing beneath that, foam caulk all seams.

Quality double or triple pane windows is next most important. Equally important is a proper installation with a double layer of foam caulk around the whole window. That means a thin layer from the inside, an air gap, and then another layer from the outside. Windows need to be shimmed from the bottom so you have enough room to get foam in there, whether the shims are needed or not for leveling.

Third most important is mass. You need a lot of mass to attenuate a wide range of frequencies. MLV is a perfect choice to accomplish this. Your new choice of siding will help some too, but MLV is on another level.

A distant fourth is sound decoupling, which is not practical for most residential applications. Also, even in the best executed scenarios, decoupling does nothing for lower frequencies, and can even increase resonance at certain higher frequencies.

I used the first three techniques for my street facing wall along 3/4 the length of my house. Completely rebuilt the wall, MLV sandwiched behind 5/8” drywall, all air gaps caulked inside and outside. Installed 4 large windows with techniques described above. I can’t tell a car is going down my street anymore, just silence, it’s wonderful.

And, ultimately, some of us just end up moving when noise keeps encroaching on our living space and the solutions are complicated and expensive. I'm not discouraging anyone from noise proofing, but after I tried technical solutions that were inadequate, and noise-cancelling headphones for when I was out in the yard, I decided I was done fighting, and found a new house for the about the same price as the old one: it's at the end of a private cul de sac that will never have road traffic.

Kudzu9, great point! Years back when we were house shopping, we fell in love with this one particular home that was perfect in every way except for road noise. We tried playing down the noise but in the end never placed a bid.

Our current neighborhood is extremely quiet (not a cul de sac which would be even better). Our main motivation for sound reduction was to actually contain sound within the house. We are remodeling an 800 sf room into a home theater / multipurpose room and want to be able to play movies and host gatherings without disturbing neighbors. With two 5000 watt subwoofers and high efficiency surround speakers, containing sound is a challenging task. Just wanted to point out to others soundproofing has benefits both ways.

I'm not an acoustic engineer - but I do know density is key in noise abatement. I'd say brick or hardiboard. A storm window would help by giving an additional 2"-3" air gap. Also if possible would be to add an additional layer of 5/8" drywall to the interior wall.

Thanks for the additional comments and detailed explanations of how to soundproof the walls. I wanted to ask about the following product -

https://www.soundproofcow.com/product/quiet-batt-30-soundproofing-insulation/?attribute_size=16in+on+center+spacing+(42sqft)&gclid=CjwKCAiA1L_xBRA2EiwAgcLKA8GCOs-PpeFBBhDUC2SYIIoHA492UxT5GB7tWxof2lYAUEJGtSyDhRoCtYgQAvD_BwE
It is called Quiet Batt 30 soundproofing insulation. The sales rep thought this would be even better than their mass loaded vinyl product. Not sure though what is underneath the siding I have - not sure if there is access to the the space between the studs or if that space is covered with plywood or something else. Does anyone know what a typical subdivision built 1978 upper story would have underneath aluminum siding?

There is also the following product from home depot which is also meant to go in between the studs. https://www.homedepot.com/p/ROCKWOOL-Safe-n-Sound-3-in-x-15-1-4-in-x-47-in-Soundproofing-Stone-Wool-Insulation-12-Bags-RXSS31525/205972532?mtc=Shopping-B-F_D22-G-D22-22_4_INSULATION-Generic-NA-Feed-PLA-NA-NA-&cm_mmc=Shopping-B-F_D22-G-D22-22_4_INSULATION-Generic-NA-Feed-PLA-NA-NA--71700000033760329-58700003913725483-92700049583712701&gclid=CjwKCAiA1L_xBRA2EiwAgcLKA8fpR5ZXggZRqehg4xp7XE6aDSOsRsjtA17HFPJAoGxzjBad-9eSdRoC5CoQAvD_BwE&gclsrc=aw.ds

Some of the mass loaded vinyl products have prop 65 warnings about antimony trioxide and would like to go as green/non-toxic as possible. The following product from home depot is listed as using eva vinyl which from what I have read so far is far less toxic than pvc vinyl. https://www.homedepot.com/p/Quiet-Wall-48-in-x-20-ft-Sound-Barrier-Quiet-Wall-QW420/309264086 If anyone has any additional comments, they will be appreciated!

David,

Sorry to tell you all the soundproof insulation marketing is not true. If you don’t have insulation in your walls just add regular insulation, it’s cheaper and has the same soundproofing effects. If you’re worried about plastic off gassing I would stay away from new cars =).

Can you sound proof your bedroom wall that faces the road ?

Dave, found this. The AcousticCurtain™ is a soundproof curtain that blocks outside noise, solving your noise problems at minimal expense and without disrupting the comforts of your home. Each AcousticCurtain™ is  hand-crafted and customized to fit the dimensions of your window.

Cotton insulation is a little better than fiberglass at blocking noise, but it's not really dense enough to be a good blocker. You could use it in conjunction with MLV or some other dense blocking material. But keep in mind that cotton insulation will need fire retardant treatment, which might go against your goal of avoiding chemicals.

The rock wool insulation has the same density problem, but not the fire retardant problem.

Actually, anything that's a good thermal insulator won't be dense enough to block much sound. But thermal insulation still has its place. It keeps noise from bouncing around inside the wall cavities, which is of some help.

I don't know anything about the Home Depot MLV. I notice that the ad doesn't specify the stuff's STC, though. You'll want to check into that before buying it. If it's as good as any other MLV's, I don't see why it wouldn't help.

As far as the safety and greenness of vinyl, if you don't like PVC, what are you planning to do for siding? If you put up PVC siding anyway, does it really make that much difference what kind of vinyl is behind it? Just asking.

Thanks for the additional replies. I will check out the AcousticCurtain. I am planning to use Certainteed shake siding which is made from polypropylene. I was 50/50 on going with lap vs shake on the style but being made from polypropylene vs vinyl made the difference. I will keep in mind the the limited ability of insulation to dampen sound.

I spoke with a contractor today and he thinks I likely don't have access to the area between the studs unless I want to drill holes in the plywood that he says is probably there and spray in foam. I also asked about using the following https://www.homedepot.com/p/SilveRboard-24-in-x-1-in-x-48-in-R5-Radiant-Acoustic-Insulation-Kit-STC-19-5-Piece-SB12AKIT/205975329 and he said the maximum thickness rigid foam they could use is 1/2" otherwise the walls will be extended out too far relative to the windows. I asked if the frame of the windows could be built out but he said no and that the windows would have to be replaced if I wanted to go with a greater than 1/2" rigid foam on the outside walls under the shake siding. I don't understand why the window frames can't be built out with wood. Again thanks for the help!

Just to follow up question - it was mentioned that proper taping and caulking the mass loaded vinyl is important so wanted to ask what type of tape would be good to use? Also, any special type of caulk? Thanks!

I just read a comment about a mass loaded vinyl product that it should be used on the interior side of the exterior wall because it is an impermeable vapor barrier and can trap moisture in the wall cavity if it is placed on the exterior side of the wall. I haven't read this anywhere else and wanted to see if this is a concern.

[MLV] is an impermeable vapor barrier and can trap moisture in the wall cavity

As I said above, AFAIK normally MLV is used on the inside, between the studs and the drywall. So I can believe that this might be true.

I can't answer what tape to use with MLV. I've seen it used, but not watched the application process closely. I'd suggest asking a supplier for advice. Or, again, consult with an acoustical engineer.

Sorry I'm not of more help. :(

I am confused about what to use if anything underneath the siding when I have it replaced in the spring. It looks like the rigid foam insulation rated to deaden sound https://www.homedepot.com/p/SilveRboard-24-in-x-1-in-x-48-in-R5-Radiant-Acoustic-Insulation-Kit-STC-19-5-Piece-SB12AKIT/205975329 is recommended to be used on exterior walls underneath siding per the following statement in the product review - " Built-in waterproofing eliminates need for house wrap or additional vapor barriers ". It is also recommended in the questions/answers section as well to be used on exterior walls. I have heard from several that mass loaded vinyl shouldn't be used because it may trap moisture underneath so why is that not ok but the SilveRboard ok to use? Also, Tyvec house wrap is advertised as allowing moisture to escape from from underneath so that is consistent with the mass loaded vinyl not being used on the exterior side of the wall. Thanks!

I asked on HomeDepot's website about using the quiet wall eva vinyl and received the following response - "The material is an impermeable vapor barrier. If there is a vapor barrier on the warm (interior) side of the wall adding the Quietwall to the cold side of the wall will trap moisture between the 2 vapor barriers and cause a condensation problem. The only time it should be used on the cold (exterior) side of the wall is if there is no vapor barrier on the other side of the wall. "

I can't think of a material that's both dense (to block noise) and permeable (to pass water vapor). Maybe a layer or two of 3/4" particle board? It's somewhat dense. Better than nothing, I guess. Sorry, I'm grasping at straws here.

Thanks for the reply and I will check out the idea of particle board and maybe see if there is a rigid foam that is permeable to water vapor and blocks sound.

The reason I thought of particle board is that 30 years ago stereo speakers that weren't expensive hardwood were often made of particle board, because of its relatively high density and low cost. I think (correct me if I'm wrong) that these days speakers are more often made of MDF, a material that's not acoustically superior, I suppose because it's even cheaper.

It takes density to block sound. In the old days they used lead. Foam by definition is not dense, so I'm skeptical of any sound control claims for foam material.

MDF is much denser than particle board and accoustically superior because of density alone. I don’t know about price since I’ve never bought particle board.

MLV is generally levels better than any type of wood material because it does not reflect sound nearly as much. It’s floppy damp nature does a really good job absorbing sound waves across all frequencies assuming you do not sandwich between two hard materials.

Foam itself does 0 to attenuate sound, but it does have a decoupling effect which helps for some frequencies but not all.

David Adams-

Just keep in mind that if you have water penetration at any time, particle board and MDF are going to swell and ultimately fall apart.

If you want to block sound in a house the first step is to address the windows as they are the first and largest entry point for sound. You need to find and research dual pane laminated windows. Opt for different width panes (3/16 + 1/4 if you can) as well as a large air gap.

Secondly is the wall. If you are doing a rebuild of the exterior research Roxul R30 for in wall. If you want to go all out find a contractor that can install Roxul comfortboard. Its 1.5 to 3 inches of sound canceling exterior insulation.

Can you share your final result? How did the sound proofing go?

Hi Wayne, CertainTeed stop making the siding that I wanted to use so I haven't been able to do the project. I am thinking about switching 2 Hardie board siding which is a fiber cement product. With it being more dense then vinyl I would think it would block sound better.

I’m going through this sound battle now. It’s so confusing!!!