How much noise should double glazing block out?

martin2345uk

Hi all,

The windows in my house (approx 16 years old) are terrible at keeping out sound, they are double glazed but the type that open...

As an example, when lying in bed at night (on the 1st floor) we can clearly hear if a car pulls up in the street outside, can clearly hear its engine running, clearly hear any chat from people in the street walking by etc.

As I find it hard to sleep with noise, it's starting to bother me more and more, and I was considering getting a new window (just in our bedroom, i'm not so bothered by the other ones).

But before I look into it, would a decent double glazed (but sill openable) window actually seal out such noise? Or is this just tha nature of openable windows?

Sorry if this is a stupid question

Thanks

Aylesbury_Duck

Three things to check. Are the double glazed units blown? Do you see moisture or misting inside the unit? If so, the gas seal between the panes has gone and with it, a small amount of sound and thermal insulation. You can replace these for less money than replacing the whole window and frame.

Secondly, have you checked that the openings shut squarely and tightly? If they do not, it might be down to hinge distortion, a fault with the handle not engaging the side bolts or simply a break, tear or crush in the seal around the opening, allowing sound to travel through.

Thirdly, do you have trickle vents? These are notorious for permitting sound to travel through them. Others have improved this by blocking the vents with anything from loft insulation to spray foam. Neither is recommended because the vents probably do an important job allowing fresh air to circulate, but you need to consider the noise/ventilation trade off.

Icecannon

Have you got room to try secondary grazing? You can buy cheap kits, will give you an idea of what a decent window will block.

The ideal window, will be fitted correctly, that is the main factor, then no trickle vents and the double glazing panes should be of different thicknesses.

No point going for a cheap plastic replacement.

Do the above and you should expect a greatly rediuced sound proofing but dont expect total silence, you will still hear all you mentioned but very much muffled.

z1a

Icecannon wrote: »

Have you got room to try secondary grazing? You can buy cheap kits, will give you an idea of what a decent window will block.

The ideal window, will be fitted correctly, that is the main factor, then no trickle vents and the double glazing panes should be of different thicknesses.

No point going for a cheap plastic replacement.

Do the above and you should expect a greatly rediuced sound proofing but dont expect total silence, you will still hear all you mentioned but very much muffled.

I think OP's after a greatly INCREASED sound proofing.

martin2345uk

Thanks for the answers so far guys...


To answer these questions:

Aylesbury_Duck wrote: »

Three things to check. Are the double glazed units blown? Do you see moisture or misting inside the unit? If so, the gas seal between the panes has gone and with it, a small amount of sound and thermal insulation. You can replace these for less money than replacing the whole window and frame.

Secondly, have you checked that the openings shut squarely and tightly? If they do not, it might be down to hinge distortion, a fault with the handle not engaging the side bolts or simply a break, tear or crush in the seal around the opening, allowing sound to travel through.

Thirdly, do you have trickle vents? These are notorious for permitting sound to travel through them. Others have improved this by blocking the vents with anything from loft insulation to spray foam. Neither is recommended because the vents probably do an important job allowing fresh air to circulate, but you need to consider the noise/ventilation trade off.

1. I can't see any evidence that the units have blown, there's no misting on the inside that I've ever seen

2. It seems to be shutting dead square, no funny angles or anything like that, though when you pull down the handle once you've closed the window, to tighten the seal, there isn't all that much resistance...

3. Yes there are trickle vents but i don't know how I would go about sealing them, they have moveable flaps over them that open/close, I keep them closed

martin2345uk

There are some decent size cracks around the edge of the frame as seen in the below photos... I assume this won!!!8217;t help the sound leakage...

Aylesbury_Duck

martin2345uk wrote: »

Thanks for the answers so far guys...


To answer these questions:



1. I can't see any evidence that the units have blown, there's no misting on the inside that I've ever seen

2. It seems to be shutting dead square, no funny angles or anything like that, though when you pull down the handle once you've closed the window, to tighten the seal, there isn't all that much resistance...

3. Yes there are trickle vents but i don't know how I would go about sealing them, they have moveable flaps over them that open/close, I keep them closed

2 and 3 seem the likely culprits then. I do not think the cracks you have photographed are the problem. It sounds as if the opening is not pulling up tight, which will either be down to some movement in the hinge or handle mechanism, or the seal around the opening has become crushed or completely detached. Trickle vents, even when closed, admit a lot of sound so investigate what you can do to improve things there, but watch out for condensation problems as a result.

stator

Get a local window repair company out. Get a quote to replace the Glazing units with Accoustic glazing units (double glazing where the two bits of glass have different thicknesses)

martin2345uk

Ok so Ive been looking more closely again this evening.

The window shuts and when you turn the handle a bolt slides upwards into the slot you can see in the second photo below. Doesnt look like that bracket thing can be adjusted. So I dont think theres much I can do there..?

As for the trickle vents, first photo below is outside the window looking up - thats one of the vents. Looks like that cover can screw off. That being the case, any suggestions what I could fill it with to reduce the noise..?

stator

crumpled up paper?

Furts

There are various puzzling matters about how your windows are designed, how they were measured and how they are installed. The default answer, without seeing them, is it all appears bodged.

But also the trickle vents - these appear to be aimed at your soffit so where do they connect to and how do they do this? Then the the internal trim at the head is covering a gap - you will not know how big until you remove it and see. Couple this with the cracks at each side and it is highly likely that sound is pouring through here.

Since you have no side trims on the internal face who knows where the sound is travelling to there? I suspect the gap/joint here with the window has not been sealed. Hence sound will be transmitted behind the wall - it could then be echoing or booming.

If you are serious about cutting your noise levels then you need to do some methodical investigation coupled with methodical diy - clearly nobody has been bothered about this in the 16 years the windows have been installed.