On Fri, 08 Sep 2006 19:22:14 +0100, Dave Plowman (News) wrote:

... shut the secondary glazing and you couldn't hear a thing from
outside.

Properly installed double glazing should do that without the
abomination of secondary glazing.

Not for best noise insulation. Single glazing with secondary spaced to
the thickness of the wall is very much better.

I have my doubts, it must be a pretty close call single or secondary
glazing 25dB attenuation each. Double glazing 50dB... (Guesstimated
figures from experience).

Certianly our new double glazing does a fine job of keeping the sound of
Tornadoes at 200' out. Most sound now appears to come through the roof
and ceilings or the older windows, (4mm gap sealed unit glassware but in
normal timber frames).


I agree it's a pain, though, unless the sound insulation is important.

I'd go for good quality well gapped (as per the regs now 20mm+?) double
glazing first and see how that fairs before using single with secondary.
If the DG doesn't perform well enough on it's own you can still add the
secondary relatively painlessly.

--
Cheers
Dave. pam is missing e-mail