double vs single glazing

[pureportugal]

hoping someone can help with a debate going on here at the moment!

when we renovate our ruin we plan to have floor-to-ceiling glass on the south wall of the living room - we have an amazing view so want to make the most of that, but also want to have as much solar gain as possible. the back (north) wall of the room is thick granite stone so that's our thermal mass. we are building a balcony with roof on the front of the house so that will shade the glass in the hot summer sun (we hope, or we'll be living in a furnace with temps here sometimes reaching over 40 deg!), but allow the lower winter sunrays into the room.

the question is, would we be better with single glazed glass to let maximum sun into the room in winter (with thick curtains and pelmets inside, plus maybe also wooden shutters outside) or would double glazing be best?

whatever the answer, would this equally apply to the smaller windows (1m x 1m) we'll be having in the other south-facing rooms (kitchen and bedroom)?

[Annpan]

Double glazing lets in the same amount of light as single (OK maybe there is 0.1% difference) but the benefit of double glazing during the winter and at night will far outweigh the extra cost of it compared with single - infact, most people would probably struggle to find single glazing units these days.

You will also probably get a better passive solar heat gain from double glazing, given that the heat will stay in and not disappear immediately.

[Green Aura]

I'm guessing we have the opposite problem to you, but our experience may help you decide.

Our house is south south-west facing and so gets full sun from fairly early in the morning. When we moved in we had single glazing which during the summer was OK - we had to have the windows open during the day to let the heat out.

In the winter it was totally inadequate - not only did the single glazing not keep any heat in, but because the prevailing wind hits us full on we had to move into the back room, to get away from the noise of the wind and rain/hail hitting the windows. Even with thick lined curtains, which helped insulate the room (a bit), the noise was unbearable. We also had to have our, very expensive to run, coal-fired central heating going non-stop for about 4 months.

The change when we had double-glazing put in was immediate - the rooms were warmer and started to dry out - I hadn't realised how damp they were! And the noise reduction was unbelievable. In the summer we still had to have the windows open - so no change there.

I toyed with the idea of shutters - I think they'd be really useful, but I'm concerned about light levels - up here we get so little daylight during the winter that I'd be loathed to shut any of it out, plus with the high winds I'm certain they'd blow away. None of which (I'm guessing) will be a problem in Portugal.

[Thomzo]

Green Aura, I'd really recommend shutters if you have room for them inside. If you put them inside the window then they are really easy to open and there is no danger of them blowing away. They are great for insulation and burglers hate them so you can leave them shut but the windows open.

Zoe

[Green Aura]

Thanks Zoe, we'll definitely give them some thought.

Don't need them to deter burglars though - crime rate nil. The outgoing bobby's caseload (a few years ago) was a bar punch-up and the mysterious death of a sheep! That's in a 500 sg.mile "beat".

[Thomzo]

Thanks Zoe, we'll definitely give them some thought.

Don't need them to deter burglars though - crime rate nil. The outgoing bobby's caseload (a few years ago) was a bar punch-up and the mysterious death of a sheep! That's in a 500 sg.mile "beat".

Well I think you need to be wary of serial sheep killers

Zoe

[Green Aura]

Most of my neighbours are more likely to be cereal killers

[lsm1066]

There are actually building regs which deal with this and you'll need to comply with them. Have a look at http://www.windowstoday.co.uk/building_regs.htm

hth
Lynne

[Odsox]

There are actually building regs which deal with this and you'll need to comply with them. Have a look at http://www.windowstoday.co.uk/building_regs.htm
hth
Lynne

Not sure that UK building regs are that important in Portugal

We have exactly the same situation as you as we had a huge floor to ceiling south facing window about 250 metres from the sea.
We get fantastic heating from the sun during the winter often not needing any extra heating for days on end.
The one draw back though was the wind. When we had storm force winds from the south or south west the windows bowed a good couple of inches with the gusts, complete with disturbing creaks and groans. The windows never broke but the double glazing seals kept rupturing, getting condensation between the panes.
Two years ago I ripped them out, built the wall up to 2 foot and got the window company to fit a new unit on top. The result was well worth doing, the view is still there (unless you lay on the floor), the wind now has no visible effect and the solar heating is not noticeably different in any way. On a sunny mid-winter day, like yesterday (and today), the temperature in that room rose to 28c from about 10 o'clock and was still 22c when we went to bed.

[Millymollymandy]

Do you have a special kind of glazing Odsox? We get no heat gain from the sun blasting into our living room in winter whatsoever because there is just no heat in the sun (whatsoever) at this time of the year.

[pureportugal]

thanks everyone!
we don't have much wind here, so don't think that will be a problem.
hmmm ... just as i typed that the door of my yurt (where i'm sat now) blew shut
odsox, how were your windows in normal (not storm force!) winds?

[Odsox]

Do you have a special kind of glazing Odsox? We get no heat gain from the sun blasting into our living room in winter whatsoever because there is just no heat in the sun (whatsoever) at this time of the year.

The original window glass was ordinary although the replacements are Pilkington K
The reason mine is probably better is the sea. During the winter months the sun is lower in the sky and the angle is just right for reflecting off the water surface. It's a scientific fact that I also use to a great extent with my amateur radio operating, that the reflection almost doubles the sunshine (or radio waves ... same thing). Anyway, it certainly works ... coupled with the clear air here in the west.
On days like today I have to have the fanlights open or it gets too hot.
Sorry

odsox, how were your windows in normal (not storm force!) winds?

They were fine in "normal" winds up to about force 8, but once the seal has gone the double glazing units just mist up inside, detroying the view and lowering the light levels.

[Green Aura]

Our windows bow dramatically in the high winds too - very scary, especially as we sit about 2 feet from them. I didn't realise it would break the seals.

The K glass helps I think - apparently it's compulsory in new windows - didn't cost us any extra (I don't think).

[lsm1066]

There are actually building regs which deal with this and you'll need to comply with them. Have a look at http://www.windowstoday.co.uk/building_regs.htm
hth
Lynne

Not sure that UK building regs are that important in Portugal

Oops!

Probably true, although always check with the local mayor's office. You never know over there In any case, whichever type of glazing you use, I'd make sure it's safety glass, whatever size it is.

Lynne

[Sky]

Just to stop condensation I would always go with double glazing.
You could always get the windows joiner made, my dad in the 60's was a joiner and I grew up in a double glazed house. He made the units himself and we were always snuggly warm.