Help! Double glazing manufacturer run-around?

I am a little surprised that if the alloy frame is insulated, that moisture condenses on it, but yet not on the glass of the windows. It does rather suggest that there is no insulation within the frame and cold from outside is being conducted through - That the alloy is conducting much more cold through, than the window glass.

No the OP stated the bi-folds aren't suffering despite as we all know they'd be the coldest surface

........"My confusion is that downstairs we have bi-fold doors and don't have the issue".....

 
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I think the problem is that it is difficult to make an aly frame profile with a thermal break that is strong enough yet also restricts the conductivity of heat.

Whilst accepting that, lack of insulation within the alloy box section would certainly compound the problem. If cold air is just allowed to circulate without hindrance in the inside the box section, then the entire box section will be cold and suffer condensation. With insulation, cold transmission through the alloy will be much more restricted. The moisture collected on the frame is evenly spread over the entire surface, rather than just close to what ought to be the colder part of the frame nearest the outside.
 
Whilst accepting that, lack of insulation within the alloy box section would certainly compound the problem. If cold air is just allowed to circulate without hindrance in the inside the box section, then the entire box section will be cold and suffer condensation. With insulation, cold transmission through the alloy will be much more restricted. The moisture collected on the frame is evenly spread over the entire surface, rather than just close to what ought to be the colder part of the frame nearest the outside.

I make timber doors. For a while I used to fit an aly threshold, but customers complained it got condensation and got mould on it
 
It may well not have a thermal break in the frame as it looks like commercial aluminium apart from the doors. Its 100mm x 50mm curtain wall with a pressure plate by the looks of it.
 
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I've gone back to the manufacturer to find out if the box frame is insulated. I have a feeling it isn't but I do know there are thermal breaks where the doors are but I don't fully understand how they work as we had a lot of discussion about them when the doors were found to be fitted incorrectly and were therefore moved forward.
 
I have a feeling it isn't but I do know there are thermal breaks where the doors are but I don't fully understand how they work as we had a lot of discussion about them when the doors were found to be fitted incorrectly and were therefore moved forward.

I would guess that the metalwork at the outside, does not form a continuous metalwork surface through to the inside. There will be a gap of some sort, maybe supported by something less conductive than metal, such as plastic.
 
Had a reply from the supplier not manufacturer and "As far as I am aware it is a hollow section"
 
ME : "Wouldn't the fact it's hollow allow cold air to travel and hit the frame where it's warm inside and cause condensation?"

THEM : "this wouldn’t happen as the frame has a thermal break inside."
 
ME : "Wouldn't the fact it's hollow allow cold air to travel and hit the frame where it's warm inside and cause condensation?"

THEM : "this wouldn’t happen as the frame has a thermal break inside."

Well then, either the thermal break is not working, or cold air is bypassing seals to get into hollow part. A lot of cold air, to cause that much condensation.

I wonder if there is some way to access the box section to blow expanding foam into it to provide insulation? Do you have, or have access to a IR thermometer, or even better a thermal camera to measure the temperature of the box section? If the insulation is decent, then it should be close to the temperatures around it, like the carpet and walls low down.
 
I have a thermal camera, much fun to be had with one. But it would give you a clearer picture of which parts are colder than the rest

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Probably too late to be useful but I just stumbled across this post which concerns problems I've encountered with new aluminium-framed windows and doors that were fitted to my place in 2107.

Apologies in advance for the rambling post!

Our alloy framed, triple-glazed windows have an WER band B rating according to a sticker on the frame (Band A+[etc] is the best insulated). Since October 2010, all new windows must be WER band C as a minimum - so yours should be at least that too. Ask the supplier.

In my opinion, it would be very difficult - if not impossible - to manufacture an aluminium-framed window with thermal insulating properties approaching the best modern plastic-framed windows. Those of us who choose alloy window and door frames for the cleaner sight-lines, security, longevity and strength have to accept the thermal insulation hit. So alloy frames will always be more prone to internal condensation than the best insulated plastic frames - doesn't mean to say it's inevitable though. It's all about the dew point of water (i.e. the point at which water vapour condenses as liquid. There are dew point charts that show at which temperature and air humidity this will occur so it's predictable.

Before I purchased my new alloy-framed windows and doors, I tried to find out if frame condensation would be an issue. It was a frustrating experience. I even asked a question on this forum. The universal response was that condensation would only occur if the room air humidity was "too high". Strictly speaking, this is only half the picture.

The window inner frame temperature is just as important in determining the dew point. And anyway, what is the optimum room humidity level for a domestic property? Turns out that's a million dollar question. Depends on what reports you read. In late 2016, when I looked into this, anything from 30% to 60% relative humidity is mentioned as an optimum range.

I purchased a humidity meter. In a room where the floor was screeded in July 2017, the humidity level was typically in the 50 to 65% range over the 2017/18 winter - because the floor wasn't completely dried out. We suffered condensation on the internal bottom ledges of both a sliding door and a floor-to-ceiling window (i.e. only on surfaces very close to the new floor level) - and it was worse than the example shown in your video. This past winter, humidity levels have been lower on average, I'd say 35 to 55%, and condensation has been minimal but not completely absent. Like your window, our sliding door does not have a trickle vent (due to my error) and that's where a little condensation formed but only on the coldest days. In the same room, our tall windows have a trickle vent and I don't remember seeing any condensation this past winter (though I live in the South and it wasn't a particularly cold winter).

Either you can increase the temperature of the inner window frame surface (other than increasing room air temperature, it's difficult to image how to do this without serious surgery) or reduce room humidity. I'd suggest getting a humidity meter and a thermal temperature 'gun' - I use both. Compare the temperature of the problematic inner window frame with another in the house that doesn't give the condensation problem. Also, check room humidities. Without a trickle vent and with no open windows, overnight humidity in a bedroom will likely be too high, in my limited experience. Get the humidity in the bedroom to 50% -ish and you may minimise the condensation problem.
 
Welcome from the future dogfonos!
I would have thought they would have solved the aluminum condensation issues by 2107 but I guess not :(

I used to make and fit ali windows and was taught it was the best of the best, Its not.
It is really mostly for commercial applications (and bifolds).
Aluminum is something like the 4th most conductive material of temp, Its will always be cold and condensate. Is it really worth the extra 10-20mm of glass?
 
Is it really worth the extra 10-20mm of glass?

I guess that's the decision we all have to make when deciding on new windows & doors. In some cases though, such as a new 3m x 4m window in our recent extension, the architectural technologist advised against plastic due to strength issues. And as you say, applies to bifolds too. Our obvious choices were either wood or aluminium - or a combination of both.

There was one manufacturer that injected insulating foam into the box sections of their aluminium windows but it was a new technique to me and I couldn't find much info or reviews about them so I avoided them (seems like an obvious idea but I didn't want to be the guinea pig).

Most manufacturers of alloy framed windows and doors use plastic strips (nylon, I think) to isolate/insulate inner from outer alloy sections but the box sections created are hollow. Some constructions are more complex (and bulky) than others and involve multiple hollow sections and sophisticated seals. I wanted to use the services of a local company so that narrowed things down considerably. I looked in detail at samples of their frame cross-sections to see how they were engineered before choosing. Also, I wanted to fit triple glazed panels so needed reasonable frame depth to allow worthwhile space between the panes - though I would have preferred even deeper panel spacing to give optimum insulation.

I still wish to fit new windows to the front and one side of my property. No big windows or sliding doors. Things may have advanced during the past 2 or 3 years. Alloy or Plastic? It's a close call this time around.
 
Thanks for all the responses.

Guess it's a valuable lesson and literally costly in don't trust the architect :)

I'll get the window fitters to add some trickle vents to the doors to increase ventilation and somehow try and combat the moisture levels.

Thanks again
 

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