Anyone had specialist acoustic double glazing fitted?

[VivaLeBeaver]

Did you use an ordinary double glazing firm or a specialist company?

I'm going round in circles firstly not knowing whether it's the size of the gap which is important or whether it's more important to have two panes of different thickness so they deflect at different rates.

So I don't really know what I want/need and need some advice as well as fitting.

[longearedbat]

I've got acoustic glazing fitted in my bedroom. I used a local double glazing company who came and measured up, then came back a few weeks later to fit the glass into the existing 3 year old window.. It took them about 15 minutes. It does the trick and I am happy with it.
I am struggling to think how much it cost, but I think it was about £300. (If you really want to know the cost, I could look it up for you)
I'm allergic to any external noise at night and I certainly can't hear a thing with the window shut.
We only did one bedroom window because I'm the one funny about noise. (We live in a rural spot, but just one car is enough to wake me up). I think it would be very expensive to get a whole house done.
It's the sort where you have two different thicknesses of glass, if that helps.

[VivaLeBeaver]

Thank you, did you find it made a big difference?

It's only the sitting room I want done - sadly it's a big bay window with 4 panes so expect it will be pricey.

[longearedbat]

Yes, but the noise wasn't that great tbh (think a car engine running type of noise. My neighbour leaves early for work and has a habit of leaving his engine running for ages very early). I discussed it with the dg company chap that came and he said he thought it would be sufficient. The next, or rather alternative, stage (of soundproofing) would have been secondary glazing, but that would have meant losing half the windowledge to accomodate it.
My last house was on an A road. I had double glazing plus secondary glazing installed on all the front windows and you couldn't hear the traffic at all. When I moved in it was single glazed and unbearable. I think for a lot of noise secondary glazing is better.

[VivaLeBeaver]

It's traffic noise. Just a village high st with a 30mph limit so not that bad. It's really only busy between about 5pm and 6:30pm but I am a bit intolerant of noise and find it irritating.

Currently double glazing is over 20 years old so it could just be its old, past it's best, etc. It might not be offering as much noise insulation as it did when new.

[Ctaftyclogs]

An ordinary double glazing firm should be able to source the correct glass. Do get a few quotes because they tend to charge a premium for acoustic glass, but it will cost more than standard double glazing.

If your windows are 20 years old I would be a little wary of replacing with acoustic glass, which is much heavier than standard double glazing, for 2 reasons: firstly noise also gets in through the gaps around the seals and the seals on an old window will likely be poor. Secondly can the window take the weight? Modern uPVC windows often don't work with heavier acoustic glass so how will an old window perform?

You also mentioned air gap v. Glass thickness. Glass thickness should always be different to stop it amplifying sound through sympathetic resonance. There are lots of thicknesses of acoustic glass and each will be better at stopping sounds of different frequencies. However as you are retro fitting you choices will be limited and anything will be better than nothing!

Air gap within the window isn't so important and won't have a major effect at this level. It only starts to make a big difference at around 100mm, which is why secondary glazing is so effective (but ugly!).

Expect to pay upwards of £150 per Metre squared for the glazing + fitting, but if you sre competent with a filler knife and a hammer you can fit it yourself, but it will be heavy! Given the age of the windows, I'd get someone in to do the work.

Good luck!

[VivaLeBeaver]

Just had a guy round to measure up.

He says the current glass is 4mm thick. Any new glass going in will have to be the same thickness.

So I'm worried there will be no noise reduction. He says the modern Pilkington K glass is better at noise reduction than the old stuff. No idea if that's right? I can't have different thickness glass. Well I assume I can if I change the frames......so not sure what to do now.

So he's going to quote for modern standard Pilkington K glass and also acoustic glass. He said the seals looked ok.

@Ctaftyclogs - when you say noise getting in through poor seals do you mean between the window frame and the brickwork? If so can anything be done to rectify/upgrade the seals? Thanks

[Ctaftyclogs]

The acoustic performance of K glass is no better than normal clear float. K glass / low E glas is about thermal performance. To confuse matters acoustic glass can be K / low E glass!

If the existing windows are uPVC /Ali and are single glazed with 4mm glass then you likely won't be able to fit acoustic glass.

If the existing double glazwed unit consists of 2 sheets of 4mm glass and has a cavity (gap between the glass) of greater than 6mm, then it will be posible to fit acoustic glass by substituting one of the sheets of a replacement unit from 4mm to 6.8mm acoustic glass.

You don't make the double glazed unith thicker - the increased thickness of glass is compensated by having a thinner cavity between the panes, which you can then gas fill with Argon /Krypton to compensate for any loss in thermal performance. The overall thicknes is then not affected.

Hope this helps?!

[VivaLeBeaver]

Thanks, yes it does help.

Confirms I don't want normal pilkington k.
Current glass is double glazed, so 2x 4mm panes with a spacer inbetween. Not sure of width of the space but the guy today said he'd do a quote for acoustic glass so I assume he thinks it can be fitted.

[VivaLeBeaver]

But 6mm is quite tiny and looking at it I would say it's more than 6mm. So only one sheet needs to be acoustic, not both of them?

[Ctaftyclogs]

Yes, only one sheet needs to be acoustic. If they are uPVC windows the cavity is probably at least 12mm, if not more, so you should have plenty of space for acoustic glass. The acoustic glass will be 6.8, 8.8, 10.8mm thick (6.8mm will most likely suffice and make a good difference to what you currently have).

Good luck!

btw you can download an app on your phone, like sound metre or similar, which measures dB. It's not an exact science but you can tell apprx. noise levels from this and do a before and after comparison. It;s really all a bit of an approximation though as noise is quite a compicated subject and there are lots of factors that affect it.

Good luck!

[ProperVexed]

We live near a busy road and had acoustic double glazing fitted by a normal window company. It has made a huge difference to the noise levels inside the house.

[galaxybrain]

We moved to a house on a busy main road and replaced most of the windows using Hugo Carter specialist windows.

www.hugocarter.co.uk/product-range/noise-reduction-windows/

They are not cheap but if you want the most noise reduction we have found them very effective.

From memory - they use different thickness (coated) glass which each deal with different frequencies of noise i.e. higher and lower pitch. They also fit them themselves as the fitting is just as important as the windows. They're used in hotels etc. They know their stuff, anyway.

[galaxybrain]

The phone apps are only as good as your phone mic (mine was rubbish) but you can buy the microphoney sound meter things online.

[VivaLeBeaver]

Just downloaded an app. It's not very busy here at weekends so only the odd car passing, dB goes up to mid 30s when a single car passes. I'm guessing it will be more when a stream of cars in the week.

That specialist website was interesting. They don't recommend acoustic glass as the sound also goes through the frames still. Which echoes what Ctaftyclogs said.

I found a recording thing on the pilkington k website where you pick a noise level/type and it plays the sound. Then you can pick a type of glass and open/close the window, swap between the non acoustic and acoustic glass. The acoustic glass seemed to make a big difference.

[johnd2]

Just to add to the great advice given already, don't listen to anyone selling you glass as double glazing sales have a reputation for telling you anything despite having little knowledge.
More concretely we had triple glazing fitted at the front for noise reasons, the overall unit is 42mm as 4,18,4,16,6, and the seals are designed to be airtight onto timber, the outside is aluminium.
On the side and rear we got 4,18,4,18,4 standard triple and the resonating noise when the cars pass is very bad, worse than the front and even seems worse than outside.
The same company also do what they call 2+1 windows which are double glazed units with an additional pane on the inside of the timber frame, like secondary glazing. They are the gold standard but not as convenient.
All the windows from them are tested and come with a table of test results and all the jazz, they are used in commercial and social housing as well as owner occupier

[Littlebluetinofdorcaspins]

WE had triple glazing fitted about 10 years ago due to serious noise issues and it has been nothing short of miraculous - saved my sanity. Sorry, don’t have any specs, but windows are upvc and replaced late Victorian sash windows.

[tentative3]

@galaxybrain could I be cheeky and ask for a ballpark price? I'm intrigued that they make their own windows as we are listed so would need wooden sash which they do. We thought that secondary glazing was our only option. It might still be depending on the prices!

[Phillipa12]

Ive just had victorian sash replaced with double glazed sash with acoustic. I wanted triple glazed as i live on an A road but they couldnt do that with external astrical bars and recommended acoustic instead, it cost an extra £400 for 3 windows, 2 are large windows but the difference is really noticable, it dosent cut out all noise but reduces it significantly. I had a local company fit mine for me.

[womblessofwimbledon]

We've just replaced our old aluminium double glazing and the noise reduction is fantastic. Before we might as well have not had windows.

[galaxybrain]

@tentative3 when we had a listed building replacing the wooden sashes cost about £1k per window - these silent ones were on average £3k per window - although our windows are pretty big and this included French windows - so about as expensive as you can get. We mentally included it in the cost of buying the house.
You can at least open them though. As I said, we live on a really busy road and it's made several rooms that were very noisy almost silent.

They replace the boxes (fittings around the window) as well to ensure effective fit.

[tentative3]

Thanks for that. The price doesn't surprise me although yes it's very ! I've just not seen an option that would work for listed buildings before so am intrigued. We're not allowed double glazing and we could have secondary but we have very shallow reveals which makes that difficult and more expensive than ordinary secondary glazing so if the silent windows are good, it might be worth us taking the leap. I think we'd only do the ones facing the street, which is three big windows.

[galaxybrain]

The windows that were already here were decent wooden sash double glazed, but quite "leaky" and we have thick walls/ recesses...

[VivaLeBeaver]

Been quoted £630 fitted for acoustic glass and £340 for pilkington k fitted. So I think for the difference I will go for the acoustic. I want to confirm with them what thickness the glass will be.

[Ctaftyclogs]

tentative3, just read your post about listed building and nit being allowed double glazing. If it's only noise you want to stop, then thick acoustic single glazing is more effective than most acoustic double glazing (i.e. 12.8mm sg v. 6.8/12/4mm dg). It won't improve heat loss, but single glazed windows, in conjunction with good acoustic seals, will see a dramatic improvement, and the planning authority have nothing on how thick the glass is, just that it be single glazed.

[VivaLeBeaver]

I’ve asked the builder how thick the glass panes are and he came back and said the whole width is 23mm. I’m assuming this includes the gap as well. Should I go back and say I want to know the actual pane mm, or is 23mm for the whole thing ok. No idea if that 2x 4mm panes with a big gap.....or 2x10mm pane with a tiny gap or something

Does @ctaftyclogs or anyone else think 23mm overall sounds ok?