Retro-fitted double glazing?

[mashman]

The houses need some ventilation...

The windows are open just about all day every day in every room.

Yes, to replace the moisture vapour saturated air (from breathing, cooking, showering etc) before it starts dropping moisture all over the place when the temperature drops in the evenings. It's not just the visible condensation that is a problem. Moisture vapour diffuses into everything (furnishings, gib, insulation and timber) as it moves through walls, floors and ceilings toward the colder face of the external cladding.

For my money proper heat pumps (with dehumidifiers) and a small amount of natural ventilation, is a healthier alternative to the HRV type systems which are (sometimes) proving to be making things a lot worse (completely destroyed ceilings) and frequently make no difference to temperature or moisture vapour (because the nonces don't understand what they are doing when installing them). All the HRV type systems are doing is moving existing poor quality air from one part of the house to another to another .

I was told this a while ago, so thought we'd try something different. 2 inch (at least) thick particle board mix with veneer overlay make upm the walls and the ceilings, no jib. The insulation is on the outside walls covered by weatherboard. Showers/bath time, the doors are closed, the extractors are left on and the window left open until the mirror condensation has gone entirely. The dehumidifier, when we run it, pulls next to nothing out of the air. We do not have gas in the house, apart from Mrs Mash (could be the issue). We have enough gaps in the house to ensure airflow, believe me. The windows in the bathrooms are left cracked all night most of the time.

It kinda blows a hole in the theory for me. You guys obviously know better and you're more than welcome to come and see for yourselves.

[steve_t]

That's what we always thought and were told... but not quite true. The brand spankin new houses we've built so far have both had double glazing. The condensation starts on the aluminium, then by morning the windows are all but dripping with condensation... that's on pretty much every window in the house.

Aluminium window frames need to be thermally broken otherwise, what you're describing happens. The aluminium conducts the cold from outside and condensation starts here.

Strange that you have a lot of condensation yet your dehumidifier pulls hardly any moisture out of the air. I'd have to suspect the dehumidifier isn't functioning well.

[mashman]

Aluminium window frames need to be thermally broken otherwise, what you're describing happens. The aluminium conducts the cold from outside and condensation starts here.

Strange that you have a lot of condensation yet your dehumidifier pulls hardly any moisture out of the air. I'd have to suspect the dehumidifier isn't functioning well.

The humidifier worked fine after the house was reclad and the builder knicked a pipe and one of the carpets got a might tad damp (windows open all day maybe?). I think you're bang on in regards to the aluminium window frames. Two sets of double glazing in two houses and as you say, it always starts on the windows frames. I'll be looking at PVC next time... by the looks of things the extra cost will be worth it.

[Maki]

What is the area around your house like, Mash? Is it in a sheltered spot lying low compared to the immediate surroundings? Are there a lot of trees nearby? Do you often get fog/mist at night? It has been raining frequently so the ground is very wet and this raises the humidity. These factors could make your case more difficult than normal. Is it possible that moisture (humid air) is somehow coming up through your floor?

Does your dehumidifier have a display that shows the relative humidity? It does not seem right that it pulls no moisture out of the air and yet you have a major problem with condensation. It sounds like it is not working.

I have looked at houses in sheltered spots with bush surroundings and these have clearly been more prone to problems with damp than most...

[flyingcrocodile46]

The windows are open just about all day every day in every room.



I was told this a while ago, so thought we'd try something different. 2 inch (at least) thick particle board mix with veneer overlay make upm the walls and the ceilings, no jib. The insulation is on the outside walls covered by weatherboard. Showers/bath time, the doors are closed, the extractors are left on and the window left open until the mirror condensation has gone entirely. The dehumidifier, when we run it, pulls next to nothing out of the air. We do not have gas in the house, apart from Mrs Mash (could be the issue). We have enough gaps in the house to ensure airflow, believe me. The windows in the bathrooms are left cracked all night most of the time.

It kinda blows a hole in the theory for me. You guys obviously know better and you're more than welcome to come and see for yourselves.

Does your house get cold quick when not heated? You can very easily over ventilate (a 3 to 5mm gap at the closing edge of each window should be more than enough). Big temperature fluctuations are problematic for moisture vapour control. A constant 18 to 22 degrees is supposedly ideal

[Maki]

The humidifier worked fine after the house was reclad and the builder knicked a pipe and one of the carpets got a might tad damp (windows open all day maybe?). I think you're bang on in regards to the aluminium window frames. Two sets of double glazing in two houses and as you say, it always starts on the windows frames. I'll be looking at PVC next time... by the looks of things the extra cost will be worth it.

knicked pipe... tad damp... Could the pipe or some other pipe still be leaking?

[flyingcrocodile46]

The humidifier worked fine after the house was reclad and the builder knicked a pipe and one of the carpets got a might tad damp (windows open all day maybe?). I think you're bang on in regards to the aluminium window frames. Two sets of double glazing in two houses and as you say, it always starts on the windows frames. I'll be looking at PVC next time... by the looks of things the extra cost will be worth it.

It is true that the frame creates a thermal bridge between outside and inside and that it and the material adjacent to it (incl the glass) will cool and then allow condensation to kick in. Timber has a higher thermal resistance than aluminim and I suspect better than PVC as well. Failure to insulate the small gap around the windows can contribute to this sort of problem as well.

[caseye]

Glad of this thread, have done the under floor and I'd have to say it's pretty much immediate and IT WORKS.
Were getting the Green Stuff, but at last minute they got some new white ones, in they went 1/2 a day 4 guys all done.
On the rates now.
Can't believe how much warmer it is, turned off the heat pump the next day, been off ever since for last three weeks.
Was going to look into double glazing then out of the blue a phone call from this energy place, they're coming to asses and advise next week.
Croc! what I do?

[mashman]

What is the area around your house like, Mash? Is it in a sheltered spot lying low compared to the immediate surroundings? Are there a lot of trees nearby? Do you often get fog/mist at night? It has been raining frequently so the ground is very wet and this raises the humidity. These factors could make your case more difficult than normal. Is it possible that moisture (humid air) is somehow coming up through your floor?

Does your dehumidifier have a display that shows the relative humidity? It does not seem right that it pulls no moisture out of the air and yet you have a major problem with condensation. It sounds like it is not working.

I have looked at houses in sheltered spots with bush surroundings and these have clearly been more prone to problems with damp than most...

We're on a hill in amongst other houses, classic suburbia (concrete jungle), only lower than the house above us, not overly sheltered from the wind, no trees, not often mist or fog but it does happen, the ground is wet but there's no condensation on the windows/panes just now (cold, but no condensation). Dunno about it coming up through the floor. It's slab with polystyrene blocks in it.

It does pull some moisture out, but a lot less than the last place and was working fine about chrimbo when we had the mini flood.

[mashman]

knicked pipe... tad damp... Could the pipe or some other pipe still be leaking?

nah, we got that sorted and had professional carpet cleaners and industrial sized everything to clean and sort that issue out.

[flyingcrocodile46]

Glad of this thread, have done the under floor and I'd have to say it's pretty much immediate and IT WORKS.
Were getting the Green Stuff, but at last minute they got some new white ones, in they went 1/2 a day 4 guys all done.
On the rates now.
Can't believe how much warmer it is, turned off the heat pump the next day, been off ever since for last three weeks.
Was going to look into double glazing then out of the blue a phone call from this energy place, they're coming to asses and advise next week.
Croc! what I do?

Take advantage Caseye. Give us a call tomorrow... or maybe a coffee run in the earlyish am

[flyingcrocodile46]

nah, we got that sorted and had professional carpet cleaners and industrial sized everything to clean and sort that issue out.

Wouldn't it be easier to install a toilet?

[mashman]

It is true that the frame creates a thermal bridge between outside and inside and that it and the material adjacent to it (incl the glass) will cool and then allow condensation to kick in. Timber has a higher thermal resistance than aluminim and I suspect better than PVC as well. Failure to insulate the small gap around the windows can contribute to this sort of problem as well.

I had a look at the thermal break stuff 2 or 3 years ago and it looked quite smart, but not perfect said the sales guy (I know, an honest sales guy)... We had wood in my dads old stoned house, single glazed, and it was condensationy... but that was in the middle of a valley in bumfuck nowhere. After that any other houses I've lived in had PVC windees and they were bloody good. the only time we really had condensation was when we were drying the washing on the radiator and the curtains were closed... even in the hard minuses of winter. Ideally I'd like to throw in a rayburn and radiator system with PVC windows, amongst other things, in the next place... although tis highly unlikely we'll be allowed to use real fire, so will probably ditch the rayburn and just implement the rest. The windows were a tight fit and were lagged, but I dunno how well tbh.

Aaaaaaand, we rarely have the heat pump on, so it ain't exactly a cold house

[mashman]

Wouldn't it be easier to install a toilet?

I'm on the super absorbent pads atm... toilet is the next step

[caseye]

Libra?????

"Take advantage Caseye. Give us a call tomorrow... or maybe a coffee run in the earlyish am"
Still no riding for me mate, Love to but can't yet.
I will call though, got yer number, cheers mate.