While trawling through endless pages and web-sites WRT ventilation etc, 
  I stumbled across the following site which I found highly interesting.
http://www.greenhouse.gov.au/yourhome/technical/fs15.htm
Thought I'd pass it on
-- 
http://gymratz.co.uk - Best Gym Equipment & Bodybuilding Supplements UK.
http://trade-price-supplements.co.uk - TRADE PRICED SUPPLEMENTS for ALL!
http://fitness-equipment-uk.com - UK's No.1 Fitness Equipment Suppliers.
http://gymratz.co.uk/hot-seat.htm - Live web-cam! (sometimes)

""Pet @ www.gymratz.co.uk ;)""  wrote in message 
news:lzlTe.103587$G8.63732@text.news.blueyonder.co.uk...

> While trawling through endless pages and web-sites WRT ventilation etc, I 
> stumbled across the following site which I found highly interesting.
> http://www.greenhouse.gov.au/yourhome/technical/fs15.htm


Isn't this all obvious? common sense?

Mary

Mary Fisher wrote:


> ""Pet @ www.gymratz.co.uk ;)""  wrote in message 
> news:lzlTe.103587$G8.63732@text.news.blueyonder.co.uk...
> 
>>While trawling through endless pages and web-sites WRT ventilation etc, I 
>>stumbled across the following site which I found highly interesting.
>>http://www.greenhouse.gov.au/yourhome/technical/fs15.htm
> 
> 
> Isn't this all obvious? common sense?
> 
> Mary
> 
> 
> 

Apparently not.

I'm amazed by how many people open their windows wide on a hot day, when 
the best thing to do is to shut all the windows and curtains until it 
gets dark.

Of course, leaving the windows open at night can be a security risk...

My grandparent's house in Brisbane was designed as first floor only - 
with a clear air path underneath, lifted away from the hot ground and 
wide verandahs to shade the windows.  This was common practice before 
aircon was invented.

Andy

In article <431e1443$0$6466$cc9e4d1f@news-text.dial.pipex.com>, Andy
Champ  writes

>
>Mary Fisher wrote:
>
>> ""Pet @ www.gymratz.co.uk ;)""  wrote in message 
>> news:lzlTe.103587$G8.63732@text.news.blueyonder.co.uk...
>> 
>>>While trawling through endless pages and web-sites WRT ventilation etc, I 
>>>stumbled across the following site which I found highly interesting.
>>>http://www.greenhouse.gov.au/yourhome/technical/fs15.htm
>> 
>> 
>> Isn't this all obvious? common sense?
>> 
>> Mary
>> 
>> 
>> 
>Apparently not.
>
>I'm amazed by how many people open their windows wide on a hot day, when 
>the best thing to do is to shut all the windows and curtains until it 
>gets dark.
>
>Of course, leaving the windows open at night can be a security risk...
>
>My grandparent's house in Brisbane was designed as first floor only - 
>with a clear air path underneath, lifted away from the hot ground and 
>wide verandahs to shade the windows.  This was common practice before 
>aircon was invented.
>

Why would the ground be hot? do they live in a volcanic area? better to
insulate the roof

-- 
David

In article ,
 David  writes:

> In article <431e1443$0$6466$cc9e4d1f@news-text.dial.pipex.com>, Andy
> Champ  writes
> >I'm amazed by how many people open their windows wide on a hot day, when 
> >the best thing to do is to shut all the windows and curtains until it 
> >gets dark.


The almost-to-the ceiling `real Georgian' sash windows were designed to be
opened bottom and top to expel warm air at the top and replace it with
cooler air from below.


> >My grandparent's house in Brisbane was designed as first floor only - 
> >with a clear air path underneath, lifted away from the hot ground and 
> >wide verandahs to shade the windows.  This was common practice before 
> >aircon was invented.
> >
> Why would the ground be hot? do they live in a volcanic area? better to
> insulate the roof


Australian houses are often built with a significant gap underneath them, as
well as with other measures on the supports, to keep ground-crawling things
of various unpleasantnesses out of the house.
-- 
SAm.

In article <dfm662$7u7$3@dulnain.stir.ac.uk>, Sam Nelson
 writes

>In article ,
> David  writes:
>> In article <431e1443$0$6466$cc9e4d1f@news-text.dial.pipex.com>, Andy
>> Champ  writes
>> >I'm amazed by how many people open their windows wide on a hot day, when 
>> >the best thing to do is to shut all the windows and curtains until it 
>> >gets dark.
>
>The almost-to-the ceiling `real Georgian' sash windows were designed to be
>opened bottom and top to expel warm air at the top and replace it with
>cooler air from below.
>
>> >My grandparent's house in Brisbane was designed as first floor only - 
>> >with a clear air path underneath, lifted away from the hot ground and 
>> >wide verandahs to shade the windows.  This was common practice before 
>> >aircon was invented.
>> >
>> Why would the ground be hot? do they live in a volcanic area? better to
>> insulate the roof
>
>Australian houses are often built with a significant gap underneath them, as
>well as with other measures on the supports, to keep ground-crawling things
>of various unpleasantnesses out of the house.


Yes, I know... but the hot ground??
-- 
David

> Apparently not.
>
> I'm amazed by how many people open their windows wide on a hot day, when
> the best thing to do is to shut all the windows and curtains until it
> gets dark.


It is possible that you really mean this, or are you being ironical?

Andy Champ wrote:

> I'm amazed by how many people open their windows wide on a hot day, when
> the best thing to do is to shut all the windows and curtains until it
> gets dark.
>


It's even better to have the curtains on the outside (shutters) to stop
the heat getting through the glass in the first place.

MBQ

wrote in message 
news:1126096638.640442.267310@o13g2000cwo.googlegroups.com...

>
> Andy Champ wrote:
>> I'm amazed by how many people open their windows wide on a hot day, when
>> the best thing to do is to shut all the windows and curtains until it
>> gets dark.
>>
>
> It's even better to have the curtains on the outside (shutters) to stop
> the heat getting through the glass in the first place.


Very difficult with bay windows ...

Mary

>
> MBQ
> 

manatbandq@hotmail.com wrote:

> Andy Champ wrote:
> > I'm amazed by how many people open their windows wide on a hot day, when
> > the best thing to do is to shut all the windows and curtains until it
> > gets dark.
> >
>
> It's even better to have the curtains on the outside (shutters) to stop
> the heat getting through the glass in the first place.
>


And get in bed with some thick pyjamas on - that'll keep the heat out!

manatbandq@hotmail.com wrote:

> Andy Champ wrote:
> > I'm amazed by how many people open their windows wide on a hot day, when
> > the best thing to do is to shut all the windows and curtains until it
> > gets dark.
> >
>
> It's even better to have the curtains on the outside (shutters) to stop
> the heat getting through the glass in the first place.
>


And get in bed with some thick pyjamas on - that'll keep the heat out!

David wrote:

> 
> Why would the ground be hot? do they live in a volcanic area? better to
> insulate the roof
> 

Because the sun shines on it.  For an extreme example, touch tarmac on a 
sunny day.

Andy

jacob@jpbutler.demon.co.uk wrote:

>>Apparently not.
>>
>>I'm amazed by how many people open their windows wide on a hot day, when
>>the best thing to do is to shut all the windows and curtains until it
>>gets dark.
> 
> 
> It is possible that you really mean this, or are you being ironical?
> 


I really mean it.  Sunshine approximates to 1Kw/M^2.  Work that out on 
your glass area.  The curtains - especially if they have pale linings - 
reflect much of that out.  When we had that hot spell the house stayed 5 
degrees C below midday peak.  This was helped by keeping an eye on the 
outside temperature, and opening all the windows and curtains upstairs 
as soon as outdoors temperature met indoor temperature.  (but not 
downstairs - we don't live in *that* nice an area...)

Of course, as has been pointed out, shutters on the outside work even 
better.

Running a PC indoors can mess this all up of course, 500W all day adds 
up.  My son's bedroom was usually hotter than outdoors!

Andy

Andy Champ wrote:


> David wrote:
> 
>>
>> Why would the ground be hot? do they live in a volcanic area? better to
>> insulate the roof
>>
> Because the sun shines on it.  For an extreme example, touch tarmac on a 
> sunny day.
> 
> Andy

But..the ground under the house doesn't get any sun shining on it....

Closed glass edifices are called greenhouses colloquially. There is a
reason for that.

Blue end spectra passes through glass but toward the red end it is
reflected back into or out of the room. So once all the available
sunlight is admitted in a closed room the radiation tends to stay in it
untill conduction or convection removes it.

However, closing the curtains, along with helping you to miss out on
the summer, will enable you to keep temps down a little. You may need
to put the lighs on instead though.

In article <431f6d57$0$13696$cc9e4d1f@news-text.dial.pipex.com>, Andy
Champ  writes

>David wrote:
>> 
>> Why would the ground be hot? do they live in a volcanic area? better to
>> insulate the roof
>> 
>Because the sun shines on it.  For an extreme example, touch tarmac on a 
>sunny day.
>
>Andy


The sun shines on it under a house? that's a clever trick unless its a
glass house with no floor
-- 
David

Weatherlawyer wrote:

> Closed glass edifices are called greenhouses colloquially. There is a
> reason for that.
>
> Blue end spectra passes through glass but toward the red end it is
> reflected back into or out of the room. So once all the available
> sunlight is admitted in a closed room the radiation tends to stay in it
> untill conduction or convection removes it.


I always thought it was the other way round. Blue end spectra is
blocked (that's why you don't get a tan indoors from the UV) and red
end gets through. The IR warms up the surfaces which then warm the room
by conduction or convection. That's why closing curtains doesn't work
as well as shutters on the outside. The curtains just warm up and then
warm the air in the room through convection.

MBQ

wrote in message 
news:1126165471.894723.87000@g43g2000cwa.googlegroups.com...

>
> Weatherlawyer wrote:
>> Closed glass edifices are called greenhouses colloquially. There is a
>> reason for that.
>>
>> Blue end spectra passes through glass but toward the red end it is
>> reflected back into or out of the room. So once all the available
>> sunlight is admitted in a closed room the radiation tends to stay in it
>> untill conduction or convection removes it.
>
> I always thought it was the other way round. Blue end spectra is
> blocked (that's why you don't get a tan indoors from the UV) and red
> end gets through. The IR warms up the surfaces which then warm the room
> by conduction or convection. That's why closing curtains doesn't work
> as well as shutters on the outside. The curtains just warm up and then
> warm the air in the room through convection.
>



No I believe Weatherlawyer is correct. Most of the UV comes through the 
glass, warms the contents of the room which then emit the heat via 
convection or infra-red which is trapped by the glass. The world acts the 
same way - if it didn't the atmosphere would be hotter higher up (nearer the 
heat source). Adiabatic cooling (colder higher) occurs because the UV from 
the sun hits the ground and is re-emitted as IR, which warms the air. 
Atmospheric conditions determine how much UV gets in and how much IR gets 
out - the "greeenhouse effect". In any case we are all correct in the end - 
shutters on the outside are definitely best!

Bob Mannix

Andy Champ wrote:

> jacob@jpbutler.demon.co.uk wrote:
> >>Apparently not.
> >>
> >>I'm amazed by how many people open their windows wide on a hot day, when
> >>the best thing to do is to shut all the windows and curtains until it
> >>gets dark.
> >
> >
> > It is possible that you really mean this, or are you being ironical?
> >
>
> I really mean it.  Sunshine approximates to 1Kw/M^2.  Work that out on
> your glass area.  The curtains - especially if they have pale linings -
> reflect much of that out.  When we had that hot spell the house stayed 5
> degrees C below midday peak.  This was helped by keeping an eye on the
> outside temperature, and opening all the windows and curtains upstairs
> as soon as outdoors temperature met indoor temperature.  (but not
> downstairs - we don't live in *that* nice an area...)
>
> Of course, as has been pointed out, shutters on the outside work even
> better.
>

Yebbut if you have air change and ventilation the inside air temp will
be at least as high as outside except for short periods of catching up
and the buffering effect of thermal mass. Inside temp will also
increase due to heat generated within the house and solar gain from
windows. If you have closed windows and no ventilation you are likely
to die a slow death due to suffocation and severe overheating! Curtains
will function as solar panels and will loose gained heat to the room -
so making no difference overall. Would have local effect though of
keeping sunlight from the immediate area but turning the heat gained
into higher air temp.
I think you have got it exactly wrong but I can see the logic - you
could argue that wearing a woolly hat and gloves will keep the heat off
your body - wrong, but a parasol will help.
The french have the best answer - high ceilings, and windows fully
opened inwards on hot days with the external louvred shutters closed on
the outside - i.e. keeping sunlight out and allowing air circulation.

Bob Mannix  wrote:

> No I believe Weatherlawyer is correct. Most of the UV comes through the 
> glass, warms the contents of the room which then emit the heat via 
> convection or infra-red which is trapped by the glass. 


I think (and certainly IME and a google-search agree)) most glass used in
domestic situations blocks most UV. I burn very very easily in the sun but
not when I'm sat behind the front-room window on a sunny day in the sun.

Rob

"Rob Summers"  wrote in message 
news:dfot73$qrb$1@north.jnrs.ja.net...

> Bob Mannix  wrote:
>> No I believe Weatherlawyer is correct. Most of the UV comes through the
>> glass, warms the contents of the room which then emit the heat via
>> convection or infra-red which is trapped by the glass.
>
> I think (and certainly IME and a google-search agree)) most glass used in
> domestic situations blocks most UV. I burn very very easily in the sun but
> not when I'm sat behind the front-room window on a sunny day in the sun.


It does block some UV (the more harmful to the skin- and eyes in the case of 
arc welders, I believe). I should correct what I said from just "UV" to 
"some UV and visible spectrum radiation" - sorry. It's also the case, as you 
imply, that greenhouse glass (plain and thin) has different characteristics 
to say double glazed Pilkington K. Nonetheless the basic principles of 
"shorter gets in and is converted to longer (wavelength) which can't get 
out" still holds and is "the greenhouse effect". In terms of the atmosphere 
and the earth there is (clearly) more going on but, by the time you have 
cancelled everything out, it's still a good appoximation. I also used the 
term "adiabatic cooling" when I meant "lapse rate cooling", while I am doing 
corrections!

Bob Mannix

"Andy Champ"  wrote in message 
news:431f6e27$0$13696$cc9e4d1f@news-text.dial.pipex.com...

>
>>>
>>>I'm amazed by how many people open their windows wide on a hot day, when
>>>the best thing to do is to shut all the windows and curtains until it
>>>gets dark.
>>
>>
>> It is possible that you really mean this, or are you being ironical?
>>
>
> I really mean it.  Sunshine approximates to 1Kw/M^2.  Work that out on 
> your glass area.  The curtains - especially if they have pale linings - 
> reflect much of that out.


Even drk ones will block it.

The front of our house faces south, in summer it can become unbearable when 
the sun is shining. We cool down immediately as we close the curtains.

I open the top windows on the north facing side and open the outside doors, 
that way there's a flow of air through the house.

There's no mystery in it, you cut out radiated heat and ventilate with 
convection currents. The house is always cooler inside than outside - even 
with the pc running - it's under oneof the north facing open windows :-)

Mary

wrote in message 
news:1126168222.419530.87190@z14g2000cwz.googlegroups.com...

>
> Andy Champ wrote:
>> jacob@jpbutler.demon.co.uk wrote:
>> >>Apparently not.
>> >>
>> >>I'm amazed by how many people open their windows wide on a hot day, 
>> >>when
>> >>the best thing to do is to shut all the windows and curtains until it
>> >>gets dark.
>> >
>> >
>> > It is possible that you really mean this, or are you being ironical?
>> >
>>
>> I really mean it.  Sunshine approximates to 1Kw/M^2.  Work that out on
>> your glass area.  The curtains - especially if they have pale linings -
>> reflect much of that out.  When we had that hot spell the house stayed 5
>> degrees C below midday peak.  This was helped by keeping an eye on the
>> outside temperature, and opening all the windows and curtains upstairs
>> as soon as outdoors temperature met indoor temperature.  (but not
>> downstairs - we don't live in *that* nice an area...)
>>
>> Of course, as has been pointed out, shutters on the outside work even
>> better.
>>
> Yebbut if you have air change and ventilation the inside air temp will
> be at least as high as outside except for short periods of catching up
> and the buffering effect of thermal mass. Inside temp will also
> increase due to heat generated within the house and solar gain from
> windows. If you have closed windows and no ventilation you are likely
> to die a slow death due to suffocation and severe overheating! Curtains
> will function as solar panels and will loose gained heat to the room -
> so making no difference overall. Would have local effect though of
> keeping sunlight from the immediate area but turning the heat gained
> into higher air temp.
> I think you have got it exactly wrong but I can see the logic - you
> could argue that wearing a woolly hat and gloves will keep the heat off
> your body - wrong, but a parasol will help.
> The french have the best answer - high ceilings, and windows fully
> opened inwards on hot days with the external louvred shutters closed on
> the outside - i.e. keeping sunlight out and allowing air circulation.


Not all French houses are like that andmany English ones are.

But what about when the shutters "function as solar panels and will loose 
gained heat to the room " ... ?

Os thatwhat caused all thoseFrench people to dir from heat?

There are times when theory is fine but I know what WORKS. I wouldn't do 
anything unless it did.

Mary

> 

Mary Fisher wrote:

> > The french have the best answer - high ceilings, and windows fully
> > opened inwards on hot days with the external louvred shutters closed on
> > the outside - i.e. keeping sunlight out and allowing air circulation.
>
> Not all French houses are like that andmany English ones are.
>
> But what about when the shutters "function as solar panels and will loose
> gained heat to the room " ... ?
>


You mean the "external louvred shutters closed on the outside"? ;-)
They don't lose any heat to the room 'cos they're outside.

MBQ

in 445385 20050908 093651 Rob_Summers@yahoo.com (Rob Summers) wrote:

>Bob Mannix  wrote:
>> No I believe Weatherlawyer is correct. Most of the UV comes through the
>> glass, warms the contents of the room which then emit the heat via
>> convection or infra-red which is trapped by the glass.
>
>I think (and certainly IME and a google-search agree)) most glass used in
>domestic situations blocks most UV. I burn very very easily in the sun but
>not when I'm sat behind the front-room window on a sunny day in the sun.
>
>Rob


Early EPROMS (2708, 2716 etc, last ones I had dealings with) had quartz
windows "because glass blocks UV" (UV was used in eprom erasers).

> > The french have the best answer - high ceilings, and windows fully
> > opened inwards on hot days with the external louvred shutters closed on
> > the outside - i.e. keeping sunlight out and allowing air circulation.
>
> Not all French houses are like that andmany English ones are.


I've never seen a British house with inward opening windows and working
shutters are extremely rare in my experience.


> But what about when the shutters "function as solar panels and will loose
> gained heat to the room " ... ?


Not if on the outside

>
> Os thatwhat caused all thoseFrench people to dir from heat?


French weather i.e. much higher temperatures than Britain.

>
> There are times when theory is fine but I know what WORKS. I wouldn't do
> anything unless it did.
> 
> Mary
> >

jacob@jpbutler.demon.co.uk wrote:

> 
> I've never seen a British house with inward opening windows and working
> shutters are extremely rare in my experience.
> 

All the windows in _my_ British house open inwards. 

Sheila

S Viemeister wrote:

> jacob@jpbutler.demon.co.uk wrote:
> >
> > I've never seen a British house with inward opening windows and working
> > shutters are extremely rare in my experience.
> >
> All the windows in _my_ British house open inwards.
>
> Sheila


That's interesting. Is it old or new? Are there others similar in the
area? Is it imitation of French style or pure Brit?

cheers

Jacob

j...@jpbutler.demon.co.uk wrote:

> S Viemeister wrote:
> > jacob@jpbutler.demon.co.uk wrote:
> > >
> > > I've never seen a British house with inward opening windows and working
> > > shutters are extremely rare in my experience.
> > >
> > All the windows in _my_ British house open inwards.
> >
> > Sheila
>
> That's interesting. Is it old or new? Are there others similar in the
> area? Is it imitation of French style or pure Brit?


PS and are the windows a later replacement in an older house?

> cheers
> 
> Jacob

jacob@jpbutler.demon.co.uk wrote:

> 
> That's interesting. Is it old or new? Are there others similar in the
> area? Is it imitation of French style or pure Brit?
>

The house is about 20 years old, and yes, there are many similar windows in
the area.
Not classic French style - quite modern ones, with a choice of limited
opening from the top (tilting in), or full opening from the side (like a
door).  Very useful for deliveries of awkwardly sized furniture, and, of
course, it makes cleaning the outside of the glass very easy!
Also - having the windows open to the inside, made it very easy to install
midge-proof screens on the outside.
 
Sheila

jacob@jpbutler.demon.co.uk wrote:

> >
> > That's interesting. Is it old or new? Are there others similar in the
> > area? Is it imitation of French style or pure Brit?
> 
> PS and are the windows a later replacement in an older house?
> 

No, they're original equipment, but I've also seen them as replacements in
older houses.  The ones in the older houses often are made to look like
traditional sash windows, so as not spoil the look of a period property.

Sheila

"S Viemeister"  wrote in message 
news:43204292.9EC8BE71@which.net...

> jacob@jpbutler.demon.co.uk wrote:
>>
>> I've never seen a British house with inward opening windows and working
>> shutters are extremely rare in my experience.
>>
> All the windows in _my_ British house open inwards.


:-)

I think it doesn't matterwhich way they open - the best are sash windows 
open top and bottom to creat a circulation.

Mary

>
> Sheila 

wrote in message 
news:1126188225.537861.118380@f14g2000cwb.googlegroups.com...

>
> S Viemeister wrote:
>> jacob@jpbutler.demon.co.uk wrote:
>> >
>> > I've never seen a British house with inward opening windows and working
>> > shutters are extremely rare in my experience.
>> >
>> All the windows in _my_ British house open inwards.
>>
>> Sheila
>
> That's interesting. Is it old or new? Are there others similar in the
> area? Is it imitation of French style or pure Brit?


Oh come on! How would she know? Perhaps the French ones are imitations of 
the British.

Mary

Mary Fisher wrote:

> "S Viemeister"  wrote in message
> news:43204292.9EC8BE71@which.net...
> > jacob@jpbutler.demon.co.uk wrote:
> >>
> >> I've never seen a British house with inward opening windows and working
> >> shutters are extremely rare in my experience.
> >>
> > All the windows in _my_ British house open inwards.
>
> :-)
>
> I think it doesn't matterwhich way they open - the best are sash windows
> open top and bottom to creat a circulation.
>
> Mary

Yes I agree (in Britain) see http://www.owdman.co.uk/joinery/ but in
France in summer the fully open window+closed shutters is loverly.

cheers

Jacob

wrote in message 
news:1126200341.536704.3050@z14g2000cwz.googlegroups.com...

>
> Mary Fisher wrote:
>> "S Viemeister"  wrote in message
>> news:43204292.9EC8BE71@which.net...
>> > jacob@jpbutler.demon.co.uk wrote:
>> >>
>> >> I've never seen a British house with inward opening windows and 
>> >> working
>> >> shutters are extremely rare in my experience.
>> >>
>> > All the windows in _my_ British house open inwards.
>>
>> :-)
>>
>> I think it doesn't matterwhich way they open - the best are sash windows
>> open top and bottom to creat a circulation.
>>
>> Mary
> Yes I agree (in Britain) see http://www.owdman.co.uk/joinery/ but in
> France in summer the fully open window+closed shutters is loverly.


So you can see the view!

I'd rather be outside in almost any weather.

The Natural Philosopher wrote:

> But..the ground under the house doesn't get any sun shining on it....


No, but the ground next to the house does, and it heats the adjacent 
air.  By lifting the house up you get it into a significantly cooler 
(and windier!) layer.

Andy

jacob@jpbutler.demon.co.uk wrote:


> Andy Champ wrote:
> 
> 
> Yebbut if you have air change and ventilation the inside air temp will
> be at least as high as outside except for short periods of catching up
> and the buffering effect of thermal mass. Inside temp will also
> increase due to heat generated within the house and solar gain from
> windows. If you have closed windows and no ventilation you are likely
> to die a slow death due to suffocation and severe overheating! Curtains
> will function as solar panels and will loose gained heat to the room -
> so making no difference overall. Would have local effect though of
> keeping sunlight from the immediate area but turning the heat gained
> into higher air temp.
> I think you have got it exactly wrong but I can see the logic - you
> could argue that wearing a woolly hat and gloves will keep the heat off
> your body - wrong, but a parasol will help.
> The french have the best answer - high ceilings, and windows fully
> opened inwards on hot days with the external louvred shutters closed on
> the outside - i.e. keeping sunlight out and allowing air circulation.
> 


Thermal inertia is what makes it work.  I maximise the heat loss at 
night, and minimise the heat gain in the day.

This isn't just theory, it really works!

Andy