Crazy Ideas To Block Traffic Noise From Yard/House

[pelican]

Hello. So glad I found this forum.

We are buying a home on the oregon coast. Nice home, nice neighborhood, large lot with lots of tall mature trees and other plants in the back yard. HOWEVER, behind the back yard is a shopping center with a large parking lot and then a busy part of highway 101 and we can hear traffic noise. It is not as bad as what you might hear in a bigger city or if we were even closer to the highway. However, we like to keep our windows open and sit on the deck and love the sweet sounds of birds and wind rustling through the trees so the traffic is loud enough to be annoying. One of the biggest draws for us to this house is all the wonderful trees which form almost a mini-forest....and we want to be able to enjoy this to the max. There is a bank in the very back maybe 10 feet and then a very gentle slope (in spots) to the back of the house so add a few more feet the house would set above the road which I would guess would be a several 100 feet away. I think though the sound might be funneling up somehow.

I have been reading about masonary fences and other tall solid fences that might reduce the noise by 10-15 decibels....but instead of spending all the money that I suspect that would cost, I have been thinking of "do it yourself a little at a time" alternatives. Some are quite crazy I think. I will list a few here and I'm hoping that you can comment on them and offer other suggestions :-)

1. Collect stones from old logging roads and/or other legal locations and start building a stone wall literally one stone at a time...need to know a cheap/free way of filling the cracks....I was thinking of filling it in with mud or something equally natural. Would the sound travel through the dirt?

2. Create a big long pile (high) of dirt and then plant plants on it. Kinda got the idea from reading about some cities putting raised areas beside highways.

3. Plexiglass - does this work as well as stone?

4. I had other ideas like planting thick stands of bamboo or bushes but from reading this forum it sounds like this might be only marginally helpful.

5. Cinderblocks and then fill with sand.

6. Painting a mural on the side of a thick wooden wall or maybe brick....but this would require buying something...maybe I could find some materials from a building be torn down??

7. A wall of used old tires filled in with something.

Any ideas or suggestions?

[supersoundproofing]

Fencing a yard against sound is one of the most difficult things to do, but here are some guidelines:
1) the fence must be very high- higher than you would expect- 10-12' as a minimum, because otherwise sound waves will just roll over it.
2) It must be closed- that is no gaps or crevices in the fencing.  No gap at the bottom!
3)What it's made of is not so important as what it's faced with: aborbent material preferably.
4) shrubbery, trees, etc will not work, contrary to what you might think or have been told. (Because sound is like water- it will find the path of least resistance).
5) Noise generators can have some masking effect if placed strategically, but add to the overall level of noise.

These are just some of the issues in a very complex subject.  But now you have a strating place on whats known about fencing ourt noise!

BTW- Hay bales are cheap, halfway attractive and when stacked high, can provide some sound blocking!

BJ Nash  Super Soundproofing co

Hopefully, others will weigh in on this!

[pelican]

Hay bales :-)  now that's an idea worth exploring :-) I was at a park the other day and I saw these high areas of dirt enclosed with rustic boards....I wonder if that could be made 8 feet tall?

I have another question...the house in question already sits much higher than the highway (which is right at 500 feet away from the backyard - I looked it up on a tax map), shouldn't I be able to get away with a lower fence? I don't know exactly what elevation it is but I'd guess at least 10 feet from the back of the yard and maybe 15 for the deck/house.

[soundproof]

<B>Here's why low fences don't work.
<P>Visualize the sound coming up and off the cars on the road as if the sound was a big soap bubble.  It expands up and outward, ever larger, losing energy as it does, of course, but huge as it rolls on over your fence!</B>

For more detailed info on this, go to:
http://www.uwm.edu/Dept/CUTS/noise/noiseb.htm

[pelican]

Thanks for the link....great illustrations!

I'm getting more and more interested in the straw bale (supposedly better than hay bales) contruction....someone told me today that they often put chicken wire and the straw bale and then stucco over the top of that....supposed to look like a stucco wall when it's done...anyone heard of this/seen this?

How does straw bales compare to masonary in it's ability to block sound?

Also someone suggested building it with logs and putting cement between the logs....anyone seen this? does it work?

[Hickory Stick]

I'm just guessing mind you, but maybe it's not so much of what the wall is made of, but how high it is?!

I've seen a chainlink fence fitted with plywood panels, hinged so they would blow open in a strong wind that seemed to work really well.  But it was high- 20' or better.

[pelican]

more research into the staw bale idea and it's looking better all the time...I thought I'd mention here on this forum that an issue seems to be breathability of the straw wall so that moisture can get out and of course a substance that also doesn't allow as much moisture in...concrete seems to be bad as it wicks the moisture toward the bale and other stuff like certain stuccos are breathable enough...if you have more info on this, I'd love to hear it since this wall/fence will be built in a very rainy climate!

Thanks again everyone :-)

[andmur]

Hi There
I've been considering a large earth berm in front of the house to cut the traffic noise.  My reseach on internet shows it is most effective noise barrier.  Plants on it help reduce noise bouncing around too.  Trouble is cost and space.  Hauling in all that dirt ain't cheap.  And you need about 3 feet of foot space for every foot you go up.  So a 5ft high berm needs 15 ft of yard.  
  So I'm thinking of a fence made out of landscape timbers.  They come in 8ft lengths, measuer 3x5 inches, about $2.50 each.   I'll stack them on the 5 inch side to a 4 ft height.  Local zoning only permits 4ft fences in front of houses.  But I can get them up higher by putting then on an earth berm.  Or maybe just start them a couple feet off the grouund and pile earth up against the bottom to seal them to the ground.  Plant some ivy or nice ground cover along the bottom.
  The result won't be 8 ft high, but it will cut off traffic line of sight to my windows, and therefore attenuate the sound, I bellieve
  Reactions?  Anybody try anything like this yet?

[toddrav]

 Straw Bale Fence - 6 ft

I'm also looking into building a straw bale fence.  They appear to offer a cheap way to build a solid fence.

My house is near a busy two lane road and set back 130' from road with some trees at property edge.  

This site recommends an 8' min height.  However, code allows me to build a 6' fence at the property line but an 8' fence would require additional setback.

Why doesn't a 6' fence deliver decent results?  It blocks the line of sight and is closer to the source.

Using the Path Length Distance model, I should expect a 11-16dB drop at higher frequencies and a 7dB drop at lower frequencies.  Won't this amount of reduction take the edge off the traffic noise when out in the yard?  

If a 10dB drop cuts the percieved sound in half, I though a 6 ft fence should move traffic noise below the level people find annoying.

I'm very new to solving sound problems.

[andmur]

From what I've read, blocking line of sight reduces the line of sound.  But it has to be line of sight from where you hear the noise.  So on first floor you may have sound blocked but on second floor not at all. Or if you stand back from the barrier and can see over it, you'll hear over it as well.   The blocking material has to be accoustically dense and without breaks too.  That's why berms work so good.  There will still be noise of course, it's not like a stream of water you can block, but  at least you can cut the racket a bit.    

[supersoundproofing]

Concerning what to cover the Straw Bales with, Tyvec bags would seem to be a durable way to encapsulate them.

Concerning 8' fences: building codes usually limit "privacy" fences to 6', but noise pollution codes are different, recognizing the need to build them high.   See http://www.nonoise.com

BJ Nash

[gayletillman]

Regarding hay fences....How do you stablize them from falling over?  Should there be some kind of material on bottom?  How long will it last? Will they mildue and rot?  I'm in southeast texas where it rains alot.  Someone help me with this please.  I need to block out the road noise asap.

[cherylmorris@comcast.net]

Easy...don't buy that house.   Heard the phrase "location, location, location???" A bad location will drop the price for the seller unless you get a buyer who doesn't know better or simply can't afford anything else.  Would you rather pay $10-20k more for a house or buy the cheaper one that has problems and may take 5+ years and thousands of people viewing it???   Never know when your company will dry up and you may have to move from the area.  Sorry to be so cynical, but I was in real estate for years and we're now in a market that may be dead slow for decades to come, not to mention so many companies downsizing and closing down nearby locations.

[wren]

I'm planning the exact same project for my house.  60ft long wall, 7-9ft high (depending on what the building department will allow) made of straw bales.  Get yourself a good book - libraries rock!  I've researched this and you want to have a concrete reinforced foundation for the wall.  Have rebar sticking up out of it every 2ft or so inbeded in the concrete.  The rebar can be anywhere from 18" - 3ft... it's kind of preference. Have bolts imbeded in concrete near the edge of foundation every 3ft or so (think like in line with railroad tracks) The foundation MUST be 6-8" above soil so moisture doesn't wick into bales.  Attach Trex or presure streated 2x4s to bolts as a kind of mudsill - now it should look like a rail road track wall. Fill gap inside with gravel for drainage incase any moisure gets into wall it can drain out bottom.  Buy high compressed rice bales - rice material has higher mold resistance.  Now get some buddies that owe you and have a straw bale implalement party!  Basically implale the first row of bales on the rebar sticking up.  Now stack the second layer, staggering the bales like bricks on a wall.  Now drive in more rebar (3-4ft long) between the 2 layers so some is sticking up for the third layer (this can also be done with sharpened wooden sticks).  Now do the next layer, staggered, and drive some more stakes through.  Continue until wall is desired height.  Now get a whole bunch of lath like boards, as tall as your wall, and lean them against the wall every 2 ft or so on both sides of wall (each board/stick should have a buddy in the same location on the other side of the wall).  Now you need a whole lot of ridged wire to thread through the bales, wrap around the opposide stick, and return to the stick on the other side, tie together tight and move 8" up and do it again and again.  This wood is what you will staple the stucco wire to and it cinches the bales tight and adds extra support.  Staple tar paper over sticks or it will crack the stucco.  Staple 2x2 wire first, then 1.75 - 3.5 awg wire (1.75 is thin and easy to mold around corners, 3.5 is stiffer if you want even more support).  Now comes the stucco.  Personally, I would hire this done.  If you get your stucco wrong you're in for a world of hurt (and cracks!).  You can also use Lime Plaster which is a breathable coating, but may need up to 5 coats, and may possibly let in too much moisture.  But if stucco gets a crack, which it will inevitably get, it will let moisture in.  I'm thinking of going with the lime plaster, (we get a fair amount of rain here in the Bay Area) but I have reservations about both.  Good luck!!  I would definitely recomend checking out books on this - pictures really help!

[wren]

Oh, and lime plaster cannot be painted or it will not breath - you can mix in a whole host of colors to suit your tastes.  Plus, lime is actually more elastic than cement stucco, so you'll have less cracking possibility.  The wire to pass between the bales is ceiling suspension wire, I think 14 awg.  You can use a weed-whacker to cut out sections in the wall if you want to have little nooks to hold things (this is mostly if you're doing a wall inside a house).  A good video is building green at www.buildinggreentv.com