A friend is getting quite desperate to move house because of traffic noise in the house. It is a really nice brick and stone built house but could do with some work to improve the situation - new door, etc.
Before embarking on spending money and finding it does not have the desired effect, is it possible to have some sort of objective survey done?
Any ideas?
Don't know about surveys - doesn't sound likely - I would have thought that the best they can hope for is someone to suggest methods of soundproofing that particular house.
For starters, is it double glazed? If not, that's got to be the first thing to do, even if just secondary glazing. Needs doing slightly differently if the object is primarily sound, rather than heat, insulation (eg, glass separation should be greater). It's got to help, and even if it turned out inadequate to prevent your friend from selling up, I can't help feeling the outlay would be recouped in the sale (if all the double glazing did was stop the attention of a buyer being instantly drawn to the traffic noise, it would probably have paid for itself!)
David
Secondary glazing is likely to achieve a far better soundproofing result than sealed D/G units.
Secondary glazing with 'thick' glass will have a vast effect. Not that expensive, either. Ordinary double glazing makes little difference to noise.
......to those interested. The above comment was nonsense. Double glazing does have an affect.
_________________________________________ Usenet Zone Free Binaries Usenet Server More than 120,000 groups Unlimited download
Indeed!
Also, I'm told (but not ever tested it) by someone who builds studios that you're suppose to have 2 different thicknesses of glass when soundproofing with double glazing. It apparently improves the range of frequencies that are suppressed.
Scott
I have found double glazing better, mainly because of the rather better seals.
It makes a phenomenal difference as aginst a rattly sash and no sealing.
True. It stops the panes acting like a diaphragm. If using secondary DG, use perforated fibre board on the walls between the two window sections.
_________________________________________ Usenet Zone Free Binaries Usenet Server More than 120,000 groups Unlimited download
Some friends of ours lived very close the flight path at Heathrow. They had secondary double glazing fitted with a 100mm gap, as they were advised that it was more efficient than replacement windows with sealed units for dealing with noise.
Ignore the troll, Scott
*Ordinary* double glazing - of the type commonly found in domestic premises is designed to minimise heat loss - not to provide sound insulation. Of course it has some effect, but that's because of the extra mass of the second layer of glass. To provide a decent amount of sound insulation the gap has to be much greater.
It's common practice to avoid having the two sheets of glass parallel to one another, to avoid the creation of standing waves. But each one will be plain thick plate glass of about 1/2" thickness. And spaced apart by some
9 inches or so at the nearest point. This will give the same sort of sound insulation as a specially constructed 9" brick cavity wall made out of heavy bricks.
So you understand less about sound than anything else? I didn't think this possible.
To prevent something acting like a 'diaphragm' at audio frequencies, you make it as rigid as possible. Or you damp it in some way. With glass windows in an acoustic insulated wall, you do this by not having the two
- or more - sheets parallel to one another, to prevent standing waves.
Just perforated board? I'd suggest you look behind it. As if.
I researched this for my own project - yes to 100mm gap, lining the gap walls with perforated board (proprietary sound absorbing stuff can't remember the name), different glass weights (so they don't reverberate in synchro) or different glass panel size for the same reason, good air seals, heaviest glass the design can accomodate. cheers Jacob
I researched this for my own project - yes to 100mm gap, lining the gap walls with perforated board (proprietary sound absorbing stuff can't remember the name), different glass weights (so they don't reverberate in synchro) or different glass panel size for the same reason, good air seals, heaviest glass the design can accomodate. cheers Jacob
The simplest and cheapest first step is to make sure all the windows, doors and other openings facing the traffic are properly draught proofed. Most noise travels through air and stopping up all the air gaps can make a surprising difference. In a detached or semi-detached house, you may also need to treat windows on the side of the house. Draught proofing will also reduce heat losses.
If the house has sash windows, which can be difficult to seal, you can do a temporary fix with gaffer (duct) tape over all the gaps. It won't look pretty, but it will give you an idea of whether it is worth going to the trouble of sealing them properly. (It almost certainly is, but it may require the complete replacement of the original windows).
Once that has been done, then you need to add mass - things like fitting a solid and heavy front door and double glazing. For best effect, fit secondary double glazing, which should be separated from the original windows by at least 50mm and preferrably by 100mm. Ideally, the glass in the secondary double glazing should be a different thickness from that in the original windows and, as we want to add mass, thicker is better than thinner. This can be quite expensive, so start with the rooms where noise reduction is most important, usually a bedroom or two. Note that secondary double glazing allows air to circulate between the two panes of glass, so it is not as effective at heat insulation as ordinary double glazing.
If the noise is worse upstairs, it may be coming in through the roof. Again, the answer is to add mass and avoid air gaps. Heavy soundproofing felt, draped across the ceiling joists and overlapped where two pieces meet, is one way. If your ceiling joists will take the weight, or you are willing to fit extra load-bearing joists, flooring it out with T&G flooring quality chipboard (not loft flooring quality), preferably 22mm or even 38mm, is another way. However, it can be difficult to make sure that all air gaps are sealed around the edges, so you may need to combine that with soundproofing felt there.
Colin Bignell
We live on a road off a busy road and which is a bus route. Apart from buses, the traffic is reasonably quiet (apart from boy racers who insist on zooming up the road). When we moved in we had old aluminium + original frames thin gap double glazing. Some of the windows didn't close properly (broken keepers causing the hinge edge to not stay in place) and so lots of noise. This was a problem for us as we noticed this soon after moving in.
We replaced the double glazing at the front with uPVC DG which had larger gaps than when the old stuff was installed - but normal gaps for modern glazing. The effect was enormous! We do still hear the buses and cars, but not enough to annoy us. Its probably a combination of the new DG and us getting used to it.
In our situation the reason it was so bad was that the old windows didn't fit properly. Once the new windows closed and sealed properly everything was better.
Normal DG is designed to keep heat in and isn't designed to stop noise. It does have an effect (as we found) but not as much as can be done using proper accoustic glazing. Basically the gap required to stop sound is much more than used in normal glazing. The size of gap is in the order of a few inches, rather than the inch you get normally. As a result secondary glazing will probably be easier/cheaper to implement the size of gaps required.
David
......our DIYing caber maker is shown to pass misinformation....he continues....
...he failed to note that Scott disgareed with him, and many others on the thread too......buit he goes on....
...of course this is not worth reading it is so bad... Sad but true.
_________________________________________ Usenet Zone Free Binaries Usenet Server More than 120,000 groups Unlimited download
nightjar Note that secondary
The air "circulates" by convection - the recommended gap for good heat retention is 25mm - this, however, is hard to get into some windows, so smaller gaps are found much more often, which aren't so good. The main benefit IMO for sealed unit D/G is the reduction or elimination of condensation on the inside of the glass that is such a pain with single glazing. Even 4-6-4 DG units are quite effective.
Perhaps you'd give some figures of the noise reduction for normal single glazing, normal double glazing, normal single glazing plus secondary glazing with an approx 6" gap, and normal double glazing with secondary glazing?
After all, you're good at searching for such things.
Hint. I've done my own tests, and after making sure the original single glazing is properly sealed, secondary glazing makes *by far* the bigger improvement.
We could not replace the SG sash windows in our house (and we would no have wanted to anyway), and could not fit secondary DG because o shutters. Simply having the windows refurbished and draughtproofed ha resulted in 10db drop in the noise level (68 -> 58). Not totally quiet but much more tolerable. Our windows were in an appalling state, thoug (1/2 inch gaps were not uncommon), and this may account for the "good result.
(averaged over three 3-minute observations with RIAA "C" weigthing a
7.30, 12.00 and 17.30 in four rooms on ground and first floor using TRS digital phonometer - I think you can still buy it at Maplin fo about £50)Be careful over secondary DG installation in listed buildings - w heard stories of people being forced to take the secondary glazing of as the conservation officer objected. It is visible, especially i located 100-150mm inside the window, which you need to get goo soundproofing.
Good luck!
David
-- Davide
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.