Dual Carriageway noise

DianaD701

Hi All , Newbie to this forum but hoping that you can give us some tips please.
We live in a house which at the bottom of our 40 foot garden runs a 4 lane dual carriageway . Reason for buying was the house had the space we desperately needed for our family of 6 plus pets at a price we could afford.
However , since lockdown and using the garden alot more the traffic noise has started to get to us and wondered what we could do to deaden it a little . We have a high wall around 2 thirds of it with a 6 foot wooden fence seperating us & next door . Then a row of approx 7 foot leylandi trees in front of the wall that faces the road. 
We did think about moving but the road is set to be widened offline in the next 5 years (Highways Agency funds funds in place) adding value to the property. Plus of course its a tricky one to sell. 
Anyone used acoustic fences or the like with any success please ? We're open to all suggestions at this stage .
Appreciate any help you can give 
Many Thanks
Di :-) 

princeofpounds

It is very hard to significantly reduce traffic noise over a short distance, perhaps unsurprisingly. There will be a benefit to having something appropriate that blocks the direct sound, but it can only improve things up to a point because the sound waves will diffract over the top or round the sides of any fence, the same way that you can still hear rather well around a corner.

A few principles might help you - a barrier will perform best if it is:
a) really tall and wide, and/or situated as close to you and/or the noise source as possible (so you are almost in it's acoustic 'shadow').
b) has significant acoustic mass i.e. made of a material that is effective at blocking sound. You don't need super high-tech material because so much noise will still get around the barrier, so any small improvement in the capability of the barrier itself will not be very perceptible.
c) has no gaps in it - sound energy can be disproportionately transmitted through tiny gaps.

Your current wall and leylandii will do relatively little (particularly the trees - good at blocking wind and light but not sound) so perhaps installing a proper barrier will help, especially if you can convince your neighbours to do so too. But it's questionable about whether the cost would be worth it. It's also a planning permission job given you'll want it over 2m tall.

If you google acoustic fencing images, you'll see lots of very tall, sturdy, fully-overlapped wooden fences. If I was investigating this further, I'd probably go off and read the british standards on acoustic fencing to see if they suggest anything about the requirements for installations to be effective.

FinallyStoppedLurking

I presume your neighbours back onto the carriageway too? May be worth speaking to them as a co-ordinated approach could reduce cost and help reduce sound if you have a long run of fencing that goes either side of the end of your garden. 

DianaD701

Thank you both for your replies .Super helpful re the barrier principles too  Am trying to find out about the British standards as suggested . All acoustic companies that i've looked at (predictably)  make claims that their fencing can help alot ! 
Unfortunately , the neighbours are elderly & almost deaf so wouldn't be willing to participate in anything like this. 
We love the house so maybe we'll just have to all invest in some decent air deafenders lol . Be madness to sell up really if our property stands to shoot up in value @£50Kish once the road is completed , just need to find a way to live with it meanwhile. 
HHHhhhmmmmm 

princeofpounds

DianaD701 said:

All acoustic companies that i've looked at (predictably)  make claims that their fencing can help alot ! 

It will - if you stand immediately behind a really wide and tall expanse of it! Unfortunately the physics are such that it's a bit like trying to create your own personal night-time using a parasol; you can create some shade but that's about it. 

Is the road at the same level as your garden, lower or higher?

DianaD701

princeofpounds said:

DianaD701 said:

All acoustic companies that i've looked at (predictably)  make claims that their fencing can help alot ! 

It will - if you stand immediately behind a really wide and tall expanse of it! Unfortunately the physics are such that it's a bit like trying to create your own personal night-time using a parasol; you can create some shade but that's about it. 

Is the road at the same level as your garden, lower or higher?

Unfortunately all at the same level ;-( 

ProDave

If the road is widened, say to 6 lanes, how will that "add value" to your house?  It will make it nosier and possibly closer.

moneysavinghero

Council installed extra soundproofing between the estate and dual carriageway of our last house, can't say that it made any noticable difference really (they had all the expensive sound experts come to survey what needed to be done, so not a quick bodge job)

DianaD701

ProDave said:

If the road is widened, say to 6 lanes, how will that "add value" to your house?  It will make it nosier and possibly closer.

Fortunately , its being widened off line so a good distance from our house . The existing dual carriageway will just become a local link road 

AdrianC

DianaD701 said:

ProDave said:

If the road is widened, say to 6 lanes, how will that "add value" to your house?  It will make it nosier and possibly closer.

Fortunately , its being widened off line so a good distance from our house . The existing dual carriageway will just become a local link road 

So a long-term benefit, but at the extent of years of construction hassle/noise/light/dust.

You've already got reasonable isolation from the road - a wall plus leylandii won't let a lot through. The single most effective thing you could probably do now is to upgrade your glazing on that side of the house... but that won't be cheap.

happy_2008

I recall viewing a house where the garden backed up to the A2 and the sound was horrendous. I didnt think it would be bad prior to viewing but it became clear that the noise was far too much