I had some double glazing units replaced by a local firm when I moved into my
house about 8 years ago. The ones I replaced had obviously failed as
condensation was forming on the inside.

Now the same units have become misty again - no condensation as such, just a
faint film on the inside which looks very ugly (particularly in sunlight). A
glazier who came to look at them told me that this was quite normal and that
one couldn't expect any double glazed units to last more than 8 to 10 years.
Is this true? Are there cheapo units around that will fail more quickly? (Or
conversely more expensive ones that last longer?).

I would appreciate any advice before I go ahead and replace them again.
Thanks

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

Mike Lane wrote:
I had some double glazing units replaced by a local firm when I moved into my
house about 8 years ago. The ones I replaced had obviously failed as
condensation was forming on the inside.

Now the same units have become misty again - no condensation as such, just a
faint film on the inside which looks very ugly (particularly in sunlight). A
glazier who came to look at them told me that this was quite normal and that
one couldn't expect any double glazed units to last more than 8 to 10 years.
Is this true? Are there cheapo units around that will fail more quickly? (Or
conversely more expensive ones that last longer?).

I would appreciate any advice before I go ahead and replace them again.
Thanks


The "faint film" you're getting is also condensation but, unless it's
between the 2 panes, there's probably nothing wrong with the units. If
it's only just started, it may be to do with the strange weather we're
having. I'd reserve judgment until that wind gets back to SW and brings
us some warm stuff

On 17 Apr, 09:47, Stuart Noble
wrote:
The "faint film" you're getting is also condensation but, unless it's
between the 2 panes, there's probably nothing wrong with the units. If
it's only just started, it may be to do with the strange weather we're
having. I'd reserve judgment until that wind gets back to SW and brings
us some warm stuff

If my experience is anything to go by, it is not condensation per se,
but the result of condensation causing salts to be leeched from the
glass, leaving a cloudy film. This film cannot be removed (at least,
not easily) even after getting access to the inside pane. My
understanding is that this is not uncommon with any double glazing
that is not truly hermetically sealed, and such units commonly have a
life of around 15 years before this clouding starts to happen -
although I have some units over 25 years old that are still clear.

crb

On Thu, 17 Apr 2008 09:47:20 +0100, Stuart Noble wrote
(in article ):

Mike Lane wrote:
I had some double glazing units replaced by a local firm when I moved into
my
house about 8 years ago. The ones I replaced had obviously failed as
condensation was forming on the inside.

Now the same units have become misty again - no condensation as such, just
a
faint film on the inside which looks very ugly (particularly in sunlight).
A
glazier who came to look at them told me that this was quite normal and
that
one couldn't expect any double glazed units to last more than 8 to 10
years.
Is this true? Are there cheapo units around that will fail more quickly?
(Or
conversely more expensive ones that last longer?).

I would appreciate any advice before I go ahead and replace them again.
Thanks


The "faint film" you're getting is also condensation but, unless it's
between the 2 panes, there's probably nothing wrong with the units. If
it's only just started, it may be to do with the strange weather we're
having. I'd reserve judgment until that wind gets back to SW and brings
us some warm stuff

Sorry, I didn't make myself clear. The film is between the two panes. If it
were not I could simply wipe it off (i.e. clean the windows!).

I was told that the space between the panes was originally evacuated, and
when the vacuum fails (after 8 - 10 years) the filming occurs and the unit
needs to be replaced. If this is true I would be tempted to get rid of the
double glazing and go back to normal windows that at least could be cleaned
properly.

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

Sorry, I didn't make myself clear. The film is between the two panes. If it
were not I could simply wipe it off (i.e. clean the windows!).

I was told that the space between the panes was originally evacuated, and
when the vacuum fails (after 8 - 10 years) the filming occurs and the unit
needs to be replaced. If this is true I would be tempted to get rid of the
double glazing and go back to normal windows that at least could be cleaned
properly.


I don't think that gap was ever a vacuum.
I've never had this happen on dg units, even on one that I accidentally
cracked. That used to steam up very slightly in the corner where the
crack was, but never got any worse.

Stuart Noble was thinking very hard :
Sorry, I didn't make myself clear. The film is between the two panes. If it
were not I could simply wipe it off (i.e. clean the windows!).

I was told that the space between the panes was originally evacuated, and
when the vacuum fails (after 8 - 10 years) the filming occurs and the unit
needs to be replaced. If this is true I would be tempted to get rid of the
double glazing and go back to normal windows that at least could be cleaned
properly.


I don't think that gap was ever a vacuum.
I've never had this happen on dg units, even on one that I accidentally
cracked. That used to steam up very slightly in the corner where the crack
was, but never got any worse.

25 years old and no such problems here. The gap is not a vacuum, but
filled to a similar or slightly less pressure to normal atmosphere.
Were it a complete vacuum, then there would be about 14 pounds per
square inch of pressure on the glass - multiplied by the area of the
glass. The seals should not fail after 8 to 10 years, they have an
indefinite lifetime, but most companies seem to provide a 10 year
guarantee - then disappear. Check the terms of your guarantee.

I have heard of one DIY solution, if you are completely stuck. It
involves drilling holes in the seal between the panels in two opposite
corners and circulating warm dry air through for some days, before
re-sealing. From memory the method used silica gell in a sealed box,
with a fish tank pump to circulate the air via small pipes in a closed
loop through the box, pump and window. Then re-seal the holes with
silicon sealer as you withdraw the pipes with the idea to leave a
slight vacuum between the panes. It is supposed to be very effective
and the slight vacuum helps pull the seals in.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

On Thu, 17 Apr 2008 20:52:04 +0100, Harry Bloomfield wrote
(in article ):

25 years old and no such problems here. The gap is not a vacuum, but
filled to a similar or slightly less pressure to normal atmosphere.
Were it a complete vacuum, then there would be about 14 pounds per
square inch of pressure on the glass - multiplied by the area of the
glass. The seals should not fail after 8 to 10 years, they have an
indefinite lifetime, but most companies seem to provide a 10 year
guarantee - then disappear. Check the terms of your guarantee.

Yes of course - I hadn't really thought about it properly. The panes would
never stand the pressure. (I should have remembered the 'collapsing can'
experiments that science teachers loved to demonstrate in the old days :-)).


I have heard of one DIY solution, if you are completely stuck. It
involves drilling holes in the seal between the panels in two opposite
corners and circulating warm dry air through for some days, before
re-sealing. From memory the method used silica gell in a sealed box,
with a fish tank pump to circulate the air via small pipes in a closed
loop through the box, pump and window. Then re-seal the holes with
silicon sealer as you withdraw the pipes with the idea to leave a
slight vacuum between the panes. It is supposed to be very effective
and the slight vacuum helps pull the seals in.

I don't think that would help. The misting is definitely not condensation -
it's more like the haze one gets on the inside of a car windscreen that's not
cleaned for a few months - not very obvious until it gets into direct
sunlight, when it looks horrible.

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

On 18 Apr, 07:35, Mike Lane wrote:
On Thu, 17 Apr 2008 20:52:04 +0100, Harry Bloomfield wrote
(in article ):

25 years old and no such problems here. The gap is not a vacuum, but
filled to a similar or slightly less pressure to normal atmosphere.
Were it a complete vacuum, then there would be about 14 pounds per
square inch of pressure on the glass - multiplied by the area of the
glass. The seals should not fail after 8 to 10 years, they have an
indefinite lifetime, but most companies seem to provide a 10 year
guarantee - then disappear. Check the terms of your guarantee.

Yes of course - I hadn't really thought about it properly. The panes would
never stand the pressure. (I should have remembered the 'collapsing can'
experiments that science teachers loved to demonstrate in the old days :-)).



I have heard of one DIY solution, if you are completely stuck. It
involves drilling holes in the seal between the panels in two opposite
corners and circulating warm dry air through for some days, before
re-sealing. From memory the method used silica gell in a sealed box,
with a fish tank pump to circulate the air via small pipes in a closed
loop through the box, pump and window. Then re-seal the holes with
silicon sealer as you withdraw the pipes with the idea to leave a
slight vacuum between the panes. It is supposed to be very effective
and the slight vacuum helps pull the seals in.

I don't think that would help. The misting is definitely not condensation -
it's more like the haze one gets on the inside of a car windscreen that's not
cleaned for a few months - not very obvious until it gets into direct
sunlight, when it looks horrible.

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

DG units nearly all fail sooner or later. 25 years is possible but
rare. 15 nearer the average. Nowt you can do about it except replace
them.

cheers
Jacob

On 18 Apr, 12:44, normanwisdom wrote:
On 18 Apr, 07:35, Mike Lane wrote:



On Thu, 17 Apr 2008 20:52:04 +0100, Harry Bloomfield wrote
(in article ):

25 years old and no such problems here. The gap is not a vacuum, but
filled to a similar or slightly less pressure to normal atmosphere.
Were it a complete vacuum, then there would be about 14 pounds per
square inch of pressure on the glass - multiplied by the area of the
glass. The seals should not fail after 8 to 10 years, they have an
indefinite lifetime, but most companies seem to provide a 10 year
guarantee - then disappear. Check the terms of your guarantee.

Yes of course - I hadn't really thought about it properly. The panes would
never stand the pressure. (I should have remembered the 'collapsing can'
experiments that science teachers loved to demonstrate in the old days :-)).

I have heard of one DIY solution, if you are completely stuck. It
involves drilling holes in the seal between the panels in two opposite
corners and circulating warm dry air through for some days, before
re-sealing. From memory the method used silica gell in a sealed box,
with a fish tank pump to circulate the air via small pipes in a closed
loop through the box, pump and window. Then re-seal the holes with
silicon sealer as you withdraw the pipes with the idea to leave a
slight vacuum between the panes. It is supposed to be very effective
and the slight vacuum helps pull the seals in.

I don't think that would help. The misting is definitely not condensation -
it's more like the haze one gets on the inside of a car windscreen that's not
cleaned for a few months - not very obvious until it gets into direct
sunlight, when it looks horrible.

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

DG units nearly all fail sooner or later. 25 years is possible but
rare. 15 nearer the average. Nowt you can do about it except replace
them.

cheers
Jacob

AIUI - the main problem is how to effectively seal two panes of glass
together *forever* given that they have to be economically knocked up
in workshops to effectively any size.
The "metal" strips visible on the inside of a DG unit contain silica
(shake an uninstalled DG unit and you can hear it rattling) to try to
prolong the life before said effects appear.
Worse if more south facing as days & days (maybe hours this summer!)
of heat stress (differential expansion, contraction etc) eventually
break the "seal" around the edge and allow either moisture in and/or
your precious Argon out.... no repairs work, dump 'em and buy more....
someone must have calculated the "whole of life" environmental cost of
all this - is it really worth bothering with DG at all??

Jim

In article ,
normanwisdom writes:

DG units nearly all fail sooner or later. 25 years is possible but
rare. 15 nearer the average. Nowt you can do about it except replace
them.

My first DG units had no failures in 25 years.
They had to be replaced because they had been
fitted to the old sash boxes which had gone rotten.

A common cause for failure is the sealed units sitting
in a puddle of water inside the frame due to poor frame
drainage. In cold weather, this freezes and wrecks the
seal. Modern uPVC frames don't attempt to seal against
the glass (would require more highly skilled fitters).
They rely on drainage holes to allow water which gets
into the frame to run out. Check these aren't blocked,
and when you take the units out for replacement, make
sure the channels under the unit are clear of debris
so water can run out.

Early frames often used a mastic seal against the glass
which was completely waterproof, and sealed units in
those tend to have a much longer life than in uPVC frames
as the unit edges remained dry.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Sun, 20 Apr 2008 09:47:42 +0100, Andrew Gabriel wrote
(in article ):

In article
,
normanwisdom writes:

DG units nearly all fail sooner or later. 25 years is possible but
rare. 15 nearer the average. Nowt you can do about it except replace
them.

My first DG units had no failures in 25 years.
They had to be replaced because they had been
fitted to the old sash boxes which had gone rotten.

A common cause for failure is the sealed units sitting
in a puddle of water inside the frame due to poor frame
drainage. In cold weather, this freezes and wrecks the
seal. Modern uPVC frames don't attempt to seal against
the glass (would require more highly skilled fitters).
They rely on drainage holes to allow water which gets
into the frame to run out. Check these aren't blocked,
and when you take the units out for replacement, make
sure the channels under the unit are clear of debris
so water can run out.


Thanks. I'll try to do that when the fitter comes to fit the replacements.
(I'm not doing it myself I'm afraid :-).

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

On 17 Apr, 08:42, Mike Lane wrote:
I had some double glazing units replaced by a local firm when I moved into my
house about 8 years ago. The ones I replaced had obviously failed as
condensation was forming on the inside.

Now the same units have become misty again - no condensation as such, just a
faint film on the inside which looks very ugly (particularly in sunlight). A
glazier who came to look at them told me that this was quite normal and that
one couldn't expect any double glazed units to last more than 8 to 10 years.
Is this true? Are there cheapo units around that will fail more quickly? (Or
conversely more expensive ones that last longer?).

I would appreciate any advice before I go ahead and replace them again.
Thanks

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

go http://doubleglazingshop.co.uk/ get a quote for replacement double
glazed units, argon gas filled seem to be the best as they last upto
35 years, its what everest and anglian fit as standard.

wrote in message
...
On 17 Apr, 08:42, Mike Lane wrote:
I had some double glazing units replaced by a local firm when I moved
into my
house about 8 years ago. The ones I replaced had obviously failed as
condensation was forming on the inside.

Now the same units have become misty again - no condensation as such,
just a
faint film on the inside which looks very ugly (particularly in
sunlight). A
glazier who came to look at them told me that this was quite normal and
that
one couldn't expect any double glazed units to last more than 8 to 10
years.
Is this true? Are there cheapo units around that will fail more quickly?
(Or
conversely more expensive ones that last longer?).

I would appreciate any advice before I go ahead and replace them again.
Thanks

--
Mike Lane (UK North Yorkshire)
To contact me replace invalid with mike underscore lane

go http://doubleglazingshop.co.uk/ get a quote for replacement double
glazed units, argon gas filled seem to be the best as they last upto
35 years, its what everest and anglian fit as standard.

Hello Mike.

I usually think of this problem being with wooden frames but a 5' square
window in our UPVC sitting room window has done the same.

Might have been the earthquake which was 3 days before I noticed the
misting. It gave us a good shaking here.

I am having the unit replaced as the frames are OK. They are about 14 years
old and were a cheapo deal as I expected to have to move again within 2
years ..... but didn't. The cost will be about £250 to 300. It has to be
toughened glas cos it's a low window sill.

Needless to say the original firm seems to have disappeared

Awful lot of spam here these days.

--
Derby, England.

Don't try to email me using "REPLY" as the email address is NoSpam. Our
email address is "thewoodies2 at ntlworld dot com"