Windows for noise prevention

[GraemeCook]

We lived for at time in Boston, USA where winter temperatures hovered around -10`C.

All windows were double hung wooden sashes about 30-36 inches wide. We had double glazing like that mentioned by Autogenous although the gap was only 6-8 mm. This had great thermal/insulation benefits and also reduced noise.

We also had secondary glazing in addition to the double glazing. This consisted of quite light aluminium, or should I say aluminum, framing with Al sash windows, similar to that commonly used in Australia for fly wire. The framing was screwed onto the outside of the window frames and the Al sashes contained 1/4 inch (6.5mm) glass instead of flywire. We put the sashes in place for winter and stored them in the basement in winter, although the sashes slid up, just like normal sash windows and they could be easily opened and closed. Beside the improvement in the thermal insulation it very noticeably reduced the sound ingress. The gap between the double glazing and the secondary glazing would have been about 100mm.

Good luck

[kevin pickering]

hi all

from what i know about pvc double glazed windows , the preferred system by manufacturers at present is a 6mm glass / 9mm gap / 6mm glass . the spacer bar is now filled with an air drying dessicant not gas . this is sufficient enough for both thermal and noise reduction control . beading in europe is tended to be put on inside of window, preferred to the outside to reduce the risk of burgulary . new retractable fly screens are also now available .

anything above 9mm gap in the double glazing industry is considered unnessary ,added to the fact it distorts the vision .

pilkington glass became a major player in the u.k these last couple of years mainly due to the fact it cut down the u.v rays only not noise reduction.(all windows had to be fitted with this external glass)

more details can be found on my website- innovated solutions via the home improvement web site .


hope this as helped .

[Wombat2]

This forum may be of help http://supersoundproofing.com/forum/index.php

The consensus on there seams to be that double glazing for heat and cold - laminated for sound.

After telling someone that who is a sound engineer he laughed at me and said laminated glass wouldn't work. That afternoon going home on the bus the driver stopped the bus for a driver change on a busy road and turned off the engine - I noted that it was quiet in the bus while there was a lot of traffic not only passing but accelerating away from traffic lights - this convinced me that the large laminated windows of the bus certainly worked to deaden the sound.

[pharmaboy2]

Hi guys, happened about a great littl;e resource written my RMIT for melb city council - has noise recomendations for lots of diffrent problems - enouhg detail, comparisons to keep the nerd happy, and not too much as to make it unintelligble.

click on the fact sheet links.

http://www.melbourne.vic.gov.au/info...a=3005&pg=3008

To sum it up - 100mm gaps are good ofr sound, 6mm gaps make very little difference. Laminated makes a large difference for high frequency noise, no diffrence for low frequency.

So - truck rumbling, heavy traffic - 100mm air gap, light traffic, talking , other outside noise, aircraft - laminated glass - and they recomend a particluar type PDE I think from memory.

edit - David - great site - i think I'll make my own acrylic window inserts now!

[myla]

hello,

for those in melbourne,

if you want to check out a double glazing system whereby upvc frames and around a 100mm air gap is used then go to the Chevron

on the cnr of commercial and st kilda rd, melbourne

the existing buildings on the corner where converted into apartments and the windows were all upgraded

thankyou

myla

[Paige]

hi everyone

Pharmaboy2 sums it up well on double glazing versus single laminated, as does Autogenous on insulation. Two additional questions...

(1) Has anyone had any experience with using Pilkington Optilam Phon glass in windows for noise reduction?

It now seems to be called Viridian VLam Hush. The "product information" PDF on this page http://www.viridianglass.com/Products/vlam-hush/default.aspx?ProductType=HouseHolder is interesting.

The table in the PDF shows that basic 3mm float glass gives a sound insualtion of 30db, compared to standard 6mm lamintate at 33db, and Vlam Hush glass: 6mm at 36db, 8mm at 38db, 10mm at 39db and 12mm at 40db.And it says that "Every 10dB is perceived as twice as loud, so that a 20dB reduction would reduce the noise by four times" (keeping in mind it means high frquencies not low frequency traffic).

We presently have say basic 3mm float glass, so if I'm reading this correctly, if we installed say the 10.5mm Vlam Hush, it would NEARLY reduce high frequency noise by half. I guess this would be best case, depending on seals, and we also have an old (brick) house which probably wouldn't help. This leads to my next question...

(2) Any thoughts on whether wall insulation is more important than upgrading windows when looking to reduce noise? (hope this is OK in this thread, not meaning to change track)

Our house is 37 years old, with original aluminium windows with aging seals, with an ACT house energy rating of 1.5 stars (average).

The ceiling insulation is apparently good, being fully insulated with fibreglass bats over loose fibreglass throughout (R 5.0).

But the EER report suggested we add additional wall insulation (R 2.5) (it is currently R 0), seal wall vents (not sure about this one as I thought some air vents were needed to allow the house to breathe), seal external doors, seal internal doors, and weather strip the entry door. Apart from thermal benefits this would no doubt help reduce noise.

I know upgrading the windows plus adding wall insulation would be best, but we have a limited bucket of money for renovations.

Thanks again