With this hot weather and working in an air-conditioned office, I've been
dreaming of trying to get our house's temperature down to something more
comfortable.

Obviously, buying an air-conditioning unit would probably be the best way -
though I think these are quite pricey (I think anything more than £150 would
be out). Also the cheaper ones are very noisy aren't they? Plus, ideally
I'd want a split unit... anyway

I've heard about these evaporative coolers - and I've also heard how people
think they're snake-oil, and I understand how they're physics are doomed to
failure - however I do know of people who claim they work. I guess the
difference is between the temperature we feel and the actual temperature.

Please correct me if I'm wrong. High humidity when its hot means that my
sweat doesn't evaporate as quickly/easily so I feel hot. Surely then
reducing the humidity is the way to go as this will allow my sweat to
evaporate more easily.

So - would a dehumidifier help to reduce how hot I feel? I've never seen
them advertised as being able to do this - whereas things which humidify
(evaporative coolers) seem to claim they do.

Basically I'm confused about it and just want a (reasonably) cheap option
(also preferable movable between living room + bedroom) to cool us down.
Fans may be the best option (price wise) I know - but I'm trying to think of
other options too.

Incidentally, what's the sort of price I should expect for a reasonable
split air-conditioner? I'd love to be able to permanently install one for
the living room - however it then seems a waste as I can't use it in the
bedroom (unless it managed to cool the whole house down!).

Thanks

D

--
To send email to me - remove references to NoSpam, and Spammer from my email
address.

"David Hearn" wrote in message
...
With this hot weather and working in an air-conditioned office, I've been
dreaming of trying to get our house's temperature down to something more
comfortable.

Obviously, buying an air-conditioning unit would probably be the best
way -
though I think these are quite pricey (I think anything more than £150
would
be out). Also the cheaper ones are very noisy aren't they? Plus, ideally
I'd want a split unit... anyway

I've heard about these evaporative coolers - and I've also heard how
people
think they're snake-oil, and I understand how they're physics are doomed
to
failure - however I do know of people who claim they work. I guess the
difference is between the temperature we feel and the actual temperature.

Please correct me if I'm wrong. High humidity when its hot means that my
sweat doesn't evaporate as quickly/easily so I feel hot. Surely then
reducing the humidity is the way to go as this will allow my sweat to
evaporate more easily.

So - would a dehumidifier help to reduce how hot I feel? I've never seen
them advertised as being able to do this - whereas things which humidify
(evaporative coolers) seem to claim they do.

Basically I'm confused about it and just want a (reasonably) cheap option
(also preferable movable between living room + bedroom) to cool us down.
Fans may be the best option (price wise) I know - but I'm trying to think
of
other options too.

Incidentally, what's the sort of price I should expect for a reasonable
split air-conditioner? I'd love to be able to permanently install one for
the living room - however it then seems a waste as I can't use it in the
bedroom (unless it managed to cool the whole house down!).

Don't bother with a./c units in the UK climate. Just enjoy the nice weather
as it comes along, so infrequently.

To cool a room, not freeze it, have some sort of forced ventilation bring in
cooler air from the north side. Heavily insulate the loft. use radiant
barrier in the loft to as this reflects heat back out from the tiles.


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On Thu, 7 Aug 2003 16:17:53 +0100, "IMM" wrote:

snip

Don't bother with a./c units in the UK climate. Just enjoy the nice weather
as it comes along, so infrequently.

I'm sure that it'll come as a surprise to you, but just as there some
(many) people who regard Milton Keynes as one of the inner circles of
Dante's hell, there are those for whom 30C/90F temperatures are
anything but "nice".

To cool a room, not freeze it, have some sort of forced ventilation bring in
cooler air from the north side. Heavily insulate the loft. use radiant
barrier in the loft to as this reflects heat back out from the tiles.

.... and the relative costs of these options are ...?

Julian


--
Julian Fowler
julian (at) bellevue-barn (dot) org (dot) uk

"Julian Fowler" wrote in message
...
On Thu, 7 Aug 2003 16:17:53 +0100, "IMM" wrote:

snip

Don't bother with a./c units in the UK climate. Just enjoy the nice
weather
as it comes along, so infrequently.

I'm sure that it'll come as a surprise to you, but just as there some
(many) people who regard Milton Keynes as one of the inner circles of
Dante's hell, there are those for whom 30C/90F temperatures are
anything but "nice".

There is something in what you say. I regard south London a hell. All
those sink estates.

To cool a room, not freeze it, have some sort of forced ventilation bring
in
cooler air from the north side. Heavily insulate the loft. use radiant
barrier in the loft to as this reflects heat back out from the tiles.

... and the relative costs of these options are ...?

I lot cheaper than an a/c that will be used a few days a year, and buttons
to run.


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"IMM" wrote in message
...

snip

Don't bother with a./c units in the UK climate. Just enjoy the nice
weather
as it comes along, so infrequently.

To cool a room, not freeze it, have some sort of forced ventilation bring
in
cooler air from the north side. Heavily insulate the loft. use radiant
barrier in the loft to as this reflects heat back out from the tiles.

Your last suggestion sounds quite a good idea actually. Our roof is unlined
and very dusty (I think due to it being unlined). I've wondered about
whether we could put something on the underside of the roof to stop all the
dust etc coming from the tiles (which is where it seems to be coming from).
If we put something reflective (on both sides?) onto the underside of the
roof this may both stop the heat coming into the loft, and also stop some of
the dust (so we may be able to use it for storage!).

Now - what would you suggest to put on the underside of the roof? I
wouldn't want to put anything which may cause problems (damp etc) and I'd
not want to do anything which a surveyor in the future may take issue with
(though they'll probably take issue with anything!)

Any suggestions?

Thanks

D

David Hearn wrote:

Your last suggestion sounds quite a good idea actually.

Until you actually stop and think about it.


Our roof is unlined
and very dusty (I think due to it being unlined). I've wondered about
whether we could put something on the underside of the roof to stop all the
dust etc coming from the tiles (which is where it seems to be coming from).
If we put something reflective (on both sides?) onto the underside of the
roof this may both stop the heat coming into the loft, and also stop some of
the dust (so we may be able to use it for storage!).

Dust yes, but heat? No, the only way to reduce heat input from
the tiles is to put thermal insulation under the tiles.

--
Grunff

"Grunff" wrote in message
...
IMM wrote:

use radiant barrier in the loft to as this reflects heat back out from
the tiles.

BwahahaHA!

A 'radiant barrier' will do nothing to cool the loft, unless the
roof is made of glass. IR from the sun doesn't penetrate the
roof tile, so the only radiative emission from the roof tile is
a direct function of it's temperature. Since this will never
exceed say 120C, it's negligible. Learn some physics.

Another know-it-all who knows nothing. The Florida Solar Energy Center
says:
"Based on our findings, we recommend that radiant barrier systems be
considered for homes with shingle roofs both in FPC's Home Energy
Improvement program as well as emphasized in FPC's new homes program where
installations would be most cost effective."

Take a look:
http://www.fsec.ucf.edu/bldg/pubs/rbs/



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"RichardS" noaccess@invalid wrote in message
. ..
"David Hearn" wrote in message
...

snip
Your last suggestion sounds quite a good idea actually. Our roof is
unlined
and very dusty (I think due to it being unlined). I've wondered about
whether we could put something on the underside of the roof to stop all
the
dust etc coming from the tiles (which is where it seems to be coming
from).
If we put something reflective (on both sides?) onto the underside of
the
roof this may both stop the heat coming into the loft, and also stop
some
of
the dust (so we may be able to use it for storage!).

Now - what would you suggest to put on the underside of the roof? I
wouldn't want to put anything which may cause problems (damp etc) and
I'd
not want to do anything which a surveyor in the future may take issue
with
(though they'll probably take issue with anything!)

Any suggestions?

Thanks

D



If you're saying that your loft is uninsulated then I'd look at sorting
that
out first. Many previous threads on the subject as to how to achieve
this -
both on the floor of the loft or between the rafters.

Insulation only seems to be stocked up in the sheds during autumn/winter,
but it's of just as much use in the summer. It's a job that's high on my
to-do list as well, when I get the time to do it.

The loft does have insulation (as thick as the joists). There's just no
felt under the tiles (ie. I can physically touch the tiles).



For your bedroom I'd recommend looking at installing a ceiling fan - they
will wire in as a direct replacement to a light fitting, but do need
proper
fixing into either a joist or a pattress between two joists. Now I know
that fans will do absolutely nothing to cool a room (they don't heat it
much
either - the motors are pretty low power) but they will make sleeping
bearable as the constant air flow ensures your body maintains efficient
evaporation. They're a cheap solution, too, ours was about £50 from a
shed,
IIRC.

I forgot to say that we've got one of these. At least, sort of. I fitted
it fine - but I've got to sort out a wobble with it - it has 3 speeds - top
speed wobbles far too much and makes a pulsing noise. The 2 slower speeds
are okay (no visible wobble, but still a quiet pulsing noise) - and we use
it as such. I need to take it down and put something under the mount
(currently just metal to lath/plaster into joist) and possibly use longer
screws. Once that is done, I'll then consider swapping the blades around
(though they claimed they were all matched in the factory).

What we've been doing is using the ceiling fan (which we don't seem to
notice does anything except make a pulsing noise which annoys us slightly)
and also a pedestal fan. Makes things more bearable - though its still too
hot....

Maybe shedding some pounds off my weight may make things a little better...
I've been meaning to do that too!

Thanks

D

"David Hearn" wrote in message
...

"IMM" wrote in message
...

snip

Don't bother with a./c units in the UK climate. Just enjoy the nice
weather
as it comes along, so infrequently.

To cool a room, not freeze it, have some sort of forced ventilation
bring
in
cooler air from the north side. Heavily insulate the loft. use radiant
barrier in the loft to as this reflects heat back out from the tiles.

Your last suggestion sounds quite a good idea actually. Our roof is
unlined
and very dusty (I think due to it being unlined). I've wondered about
whether we could put something on the underside of the roof to stop all
the
dust etc coming from the tiles (which is where it seems to be coming
from).
If we put something reflective (on both sides?) onto the underside of the
roof this may both stop the heat coming into the loft, and also stop some
of
the dust (so we may be able to use it for storage!).

Now - what would you suggest to put on the underside of the roof? I
wouldn't want to put anything which may cause problems (damp etc) and I'd
not want to do anything which a surveyor in the future may take issue with
(though they'll probably take issue with anything!)

Heavy dust on radiant barrier reduces its effectiveness. Plug the holes
first.


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"Grunff" wrote in message
...
David Hearn wrote:

Your last suggestion sounds quite a good idea actually.

Until you actually stop and think about it.

But it needs a thinker to think about it. And you fail in this respect.


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On Thu, 7 Aug 2003 16:43:35 +0100, "IMM" wrote:


"Grunff" wrote in message
...
IMM wrote:

use radiant barrier in the loft to as this reflects heat back out from
the tiles.

BwahahaHA!

A 'radiant barrier' will do nothing to cool the loft, unless the
roof is made of glass. IR from the sun doesn't penetrate the
roof tile, so the only radiative emission from the roof tile is
a direct function of it's temperature. Since this will never
exceed say 120C, it's negligible. Learn some physics.

Another know-it-all who knows nothing. The Florida Solar Energy Center
says:
"Based on our findings, we recommend that radiant barrier systems be
considered for homes with shingle roofs both in FPC's Home Energy
Improvement program as well as emphasized in FPC's new homes program where
installations would be most cost effective."

Hmmm ... I don't suppose its a *teeny* bit possible that this might
apply to US-style houses built in Florida, and might not be applicable
to conditions here?

:-)

Julian

--
Julian Fowler
julian (at) bellevue-barn (dot) org (dot) uk

"Julian Fowler" wrote in message
...
On Thu, 7 Aug 2003 16:43:35 +0100, "IMM" wrote:


"Grunff" wrote in message
...
IMM wrote:

use radiant barrier in the loft to as this reflects heat back out
from
the tiles.

BwahahaHA!

A 'radiant barrier' will do nothing to cool the loft, unless the
roof is made of glass. IR from the sun doesn't penetrate the
roof tile, so the only radiative emission from the roof tile is
a direct function of it's temperature. Since this will never
exceed say 120C, it's negligible. Learn some physics.

Another know-it-all who knows nothing. The Florida Solar Energy Center
says:
"Based on our findings, we recommend that radiant barrier systems be
considered for homes with shingle roofs both in FPC's Home Energy
Improvement program as well as emphasized in FPC's new homes program
where
installations would be most cost effective."

Hmmm ... I don't suppose its a *teeny* bit possible that this might
apply to US-style houses built in Florida, and might not be applicable
to conditions here?

Did you read it? No. If they work in Florida they will work here. A
barrier under tiles is well a barrier under tiles anywhere.


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"David Hearn" wrote in message
...
With this hot weather and working in an air-conditioned office, I've been
dreaming of trying to get our house's temperature down to something more
comfortable.

Our dining room faces due south and there's a large bay windo which lets all
the sun in. It's horrible.

The answer is to draw the curtains on the south side of the house. The rest
of the house isn't a problem.

We open windows of course to catch whatever breath of moving air there is.
But covering windows seems to be the most effective solution and costs
nothing. If you have curtains ... in the caravan we lower the venetian
blinds.

Mary

"RichardS" noaccess@invalid wrote

For your bedroom I'd recommend looking at installing a ceiling fan


It's not such a sophisticated solution, but I wouldn't be without my 3KW fan
heater, which also has a cool setting. It has the great benefit that it can
be moved from room to room. Over the last couple of days the cool setting
has been bliss, since I can focus the moving air exactly where I want. It
may not technically cool the room, but it feels as if it does, and that's
what matters.

I primarily keep it in case the central heating ever breaks down, just as I
keep a few candles and matches in case of a power cut. But it's also useful
for quick spot heating, and as a very fast hairdryer in an emergency.
Although I've never tried it, I imagine it could also be used as a quick
fabric drier - you know, if you need to rinse spaghetti sauce off of your
favourite party frock without getting changed in the middle of your dinner
party!

In other words, it can be of use all year round and for several purposes -
far more sensible than blowing a fortune, I think, during a
once-in-several-years heatwave.

Barbara

On Thu, 7 Aug 2003 17:20:35 +0100, "IMM" wrote:



Hmmm ... I don't suppose its a *teeny* bit possible that this might
apply to US-style houses built in Florida, and might not be applicable
to conditions here?

Did you read it? No. If they work in Florida they will work here. A
barrier under tiles is well a barrier under tiles anywhere.


Shingles are made from Western Red Cedar, not the material that is
used for roof tiles here.




..andy

To email, substitute .nospam with .gl

"IMM" wrote in message
...

Did you read it? No. If they work in Florida they will work here. A
barrier under tiles is well a barrier under tiles anywhere.


Have to say, I'm in agreement with the other posters here. From a physics
point of view, putting a reflective material where no direct IR radiation
hits it is going to be of negligible use - also with tiles, they will
contain the heat for a good while, which will not help either. Putting a
thick insulating material under it will be a better option - be careful
there's enough ventilation though.

Now if you put tin foil on top of your roof tiles it WILL do an excellent
job!! Not so sure your neighbours or the local council will go with you on
that though after you blind everyone who passes by ;o)

Think of it like this - if you put spuds on the BBQ in foil, you'll burn
your hand off if you pick up the foil because the potato inside it is hot
and in contact with it. If you put a sheet of foil between you and the
flames, it will be a very effective heat barrier.


a

"Julian Fowler" wrote in message
...
On Thu, 7 Aug 2003 17:20:35 +0100, "IMM" wrote:


"Julian Fowler" wrote in message
.. .

snip

Hmmm ... I don't suppose its a *teeny* bit possible that this might
apply to US-style houses built in Florida, and might not be applicable
to conditions here?

Did you read it? No.

Yes, actually ... additionally, I clearly understood a lot more than
you did. Start with the very first page -- note the temperatures
cited (attic temp reduced from 135F to 120F)? Note the fact that this
an academic research project report and "not intended to represent the
views and opinions of the Florida Solar Energy Center". Note that the
attic spaces shown are filled w/ HVAC ducting??

If they work in Florida they will work here. A
barrier under tiles is well a barrier under tiles anywhere.

Who said anything about tiles - the report, which you quoted, referred
to shingles - a different roofing material used in a different
construction technique and a different climate from that in the UK.
Plus, you were citing this to back up your assertion that a/c is
unnecessary in this country ... try finding a house without a/c in
Florida!

read the site some more



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Abso wrote:

- Switch off everything electrical you can (a TV left on can dissipate several
hundred watts in heat. Even when in standby the dissipation is only a little
lower - switch it off entirely).

That would be one mutha TV. My 32" Sony consumes 90W when on,
and 0.5W on standby.

--
Grunff

Abso wrote:


- Switch off everything electrical you can (a TV left on can dissipate several
hundred watts in heat.

Dubious. A 100W lightbulb won't generate 100 watts of heat, neither
will a 100W heater for that matter.

--
jc

Mary Fisher wrote:

The details are unimportant. The principle is right.

Weeel, I disagree there. The detail, in this case, is everything.

If you have a room with a PC (200W) and a large TV (100W) in it,
then you're dumping in say 300W.

Say the room has a south facing window, 4'x5' (total area
~2m^2), then on a sunny day the light coming in through that
window can contribute a couple of kW to the room.

That's a much more significant heat input. Fitting a blind will
have a *much* bigger effect than switching off the PC and the TV.

That isn't to say it's not a good idea to switch things off when
not using them (except PCs, but that's a whole other kettle).
Just that in terms of keeping a room cool in the summer, they
are minor points.

--
Grunff

"Simon Gardner" [dot]co[dot]uk wrote in message
...
In article ,
wrote:

In other words, it can be of use all year round and for several
purposes -
far more sensible than blowing a fortune, I think, during a
once-in-several-years heatwave

It's not "once in several years". The temperature and or humidity gets way
to high every year for a good three months. Why bother with the central
heating? After all, mostly you don't need it. I mean, just for December,
Jan, Feb, it's hardly worth it, eh?

It is easy to keep cool, but not keep warm. Most people like hot weather,
that is why we all flock to the Med each year.




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"Julian Fowler" wrote in message
...
On Thu, 7 Aug 2003 20:08:51 +0100, "IMM" wrote:


"Julian Fowler" wrote in message

snip

read the site some more

... so that I can extract the words that support your misunderstanding
of these particular research results and ignore all the rest? I have
only glanced at the main body of the paper; however, if (as you seem
to be suggesting) that contains important information that is not
covered in the executive summary then I suggest that this is a very
poorly written paper (which could suggest that the underlying research
ain't too hot either).

So that means you haven't looked all over the institutions site then.


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It is easy to keep cool, but not keep warm.

Wrong.

Most people like hot weather,

Wrong.

that is why we all flock to the Med each year.

Wrong.




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"IMM" wrote in message
...

"Simon Gardner" [dot]co[dot]uk wrote in message
...
In article ,
wrote:

In other words, it can be of use all year round and for several
purposes -
far more sensible than blowing a fortune, I think, during a
once-in-several-years heatwave

It's not "once in several years". The temperature and or humidity gets
way
to high every year for a good three months. Why bother with the central
heating? After all, mostly you don't need it. I mean, just for December,
Jan, Feb, it's hardly worth it, eh?

It is easy to keep cool, but not keep warm. Most people like hot weather,
that is why we all flock to the Med each year.

You can't be right mate! It's easy to get warm and keep warm in almost any
situation, it's nigh on impossible to keep cool and continue with everyday
activities in recent weeks. As for the Med, help yourself to the misery if
that's what you like, I shall be in Scotland or further north in the next
heatwave.



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On Thu, 7 Aug 2003 19:28:39 UTC, "Abso" wrote:

- Switch off everything electrical you can (a TV left on can dissipate several
hundred watts in heat. Even when in standby the dissipation is only a little
lower - switch it off entirely).

Generally, I agree...but as for the TV...just bought a 14 inch (OK, not
big) with a standby *consumption* (OK, mostly heat) of 2.9 watts. Not
really a lirtle less than a few hundred...! Even multiplying for a
decent sized TV, I can't see it reaching ewven 50 watts.

Computer monitors...easy to switch off, a major power hig, and the bit
that actually wears out a decent amount when on, not to mention the
largest fire risk in a PC...turn that off always when not using. Easier
and quicker (and thus more likely to be done) than the PC itself. And of
course engage power saving on the PC but don't allow the hard disk to
spin down.

- Leave windows open through the night when the outside air is cool and close
windows during the hottest hours of the day (say 11am til 5pm). Quite
counter-intuitive this, but you are likely to find that by leaving the windows
open, the air entering the room is warmer than the room was previously.

Yes, very much the case here yesterday. North-east Kent coast, south
westerly wind...very hot! However, today it was the opposite. Noth
westerly wind, off the sea, cooler than inside...

- Pull curtains / blinds to prevent the sunlight (and heat) falling on the
internal surfaces of the room and heating them.

Yup. Just bought a big blind for a big, bare window today! But it was
too hot to fit it....

--
Bob Eager
rde at tavi.co.uk
PC Server 325*4; PS/2s 9585, 8595, 9595*2, 8580*3,
P70, PC/AT..

On Thu, 7 Aug 2003 20:17:18 UTC, "Mary Fisher"
wrote:

The details are unimportant. The principle is right.

I think the details are quite important when the figure is two orders of
magnitude out.....!

--
Bob Eager
rde at tavi.co.uk
PC Server 325*4; PS/2s 9585, 8595, 9595*2, 8580*3,
P70, PC/AT..

"Grunff" wrote
| That's a much more significant heat input. Fitting a blind will
| have a *much* bigger effect than switching off the PC and the TV.
| That isn't to say it's not a good idea to switch things off when
| not using them (except PCs, but that's a whole other kettle).
| Just that in terms of keeping a room cool in the summer, they
| are minor points.

And part of the point of keeping a room cool is to be able to sit here and
use the PC.

Owain

"IMM" wrote in message
...
It is easy to keep cool, but not keep warm. Most people like hot weather,
that is why we all flock to the Med each year.


Every so often I find someone with the same infuriating views on
temperature. They're the gits that are allergic to aircons in the office
and turn them off. In the winter they have the heaters on full and sickly
hot. As other posters have said - you can always wear more, not less!!


Grrrrr ... ;P



a

On Thu, 7 Aug 2003 23:05:21 UTC, "al" wrote:

"Mary Fisher" wrote in message
t...
It is easy to keep cool, but not keep warm.
Wrong.
Most people like hot weather,
Wrong.
that is why we all flock to the Med each year.
Wrong.

You sound like my kinda girl Mary ... short & to the point!! ;o)

Never knew how tall she was before....!

--
Bob Eager
rde at tavi.co.uk
PC Server 325*4; PS/2s 9585, 8595, 9595*2, 8580*3,
P70, PC/AT..

"IMM" wrote in message
...

"Julian Fowler" wrote in message
...
On Thu, 7 Aug 2003 17:20:35 +0100, "IMM" wrote:


"Julian Fowler" wrote in message
.. .

snip

Hmmm ... I don't suppose its a *teeny* bit possible that this might
apply to US-style houses built in Florida, and might not be
applicable
to conditions here?

Did you read it? No.

Yes, actually ... additionally, I clearly understood a lot more than
you did. Start with the very first page -- note the temperatures
cited (attic temp reduced from 135F to 120F)? Note the fact that this
an academic research project report and "not intended to represent the
views and opinions of the Florida Solar Energy Center". Note that the
attic spaces shown are filled w/ HVAC ducting??

If they work in Florida they will work here. A
barrier under tiles is well a barrier under tiles anywhere.

Who said anything about tiles - the report, which you quoted, referred
to shingles - a different roofing material used in a different
construction technique and a different climate from that in the UK.
Plus, you were citing this to back up your assertion that a/c is
unnecessary in this country ... try finding a house without a/c in
Florida!

read the site some more


This quote seems applicable...

"tile roofs experience less attic heating and thus would likely produce less
benefits from an RBS (Beal and Chandra, 1995; Parker and Sherwin, 1998). "

Most of the emphasis of the report is on energy savings from reduced power
consumption by cooling systems - some 9% on average. However for those homes
without aircon - and for the UK I would imagine that is pretty damn near
most - such savings are of no consequence. Then there is the average
decrease in interior temperature of 2 degrees farenheit, but that is for a
sample where 90% of the homes used composite shingle rather than tile.

So for the typical UK home with no aircon and a tile roof, the benefits are
minimal, and far outweighed by the cost of installation.

A nice idea if you live in Florida, but bugger all use in the UK.

Cheers
Clive

IMM wrote:
It is easy to keep cool, but not keep warm.

Huh? you can add unlimited layers of clothing to keep warm, but once
you're naked you can't take any more off.

Most people like hot weather,
that is why we all flock to the Med each year.


There's a difference - humidity; dry heat doesn't feel as hot as humid heat.

IMM wrote:

Heavy dust on radiant barrier reduces its effectiveness. Plug the holes
first.

Exactly how much heat radiation are you expecting to get off the under
side of a hot tile?

The only way a radiation reflective layer is going to have a major
effect is if you put it on the outside of your tiles..... go wrap your
house in tin foil!


--
Cheers,

John.

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David Hearn wrote:

Obviously, buying an air-conditioning unit would probably be the best way -
though I think these are quite pricey (I think anything more than ?150 would
be out). Also the cheaper ones are very noisy aren't they? Plus, ideally
I'd want a split unit... anyway

Depends on what you mean by noisy... the mono block units are noisy as
in the noise of a fridge freezer combined with a large fan - i.e.
irritation if you are trying to watch TV or sleep - but not as loud as a
vacuum cleaner!

I've heard about these evaporative coolers - and I've also heard how people
think they're snake-oil, and I understand how they're physics are doomed to
failure - however I do know of people who claim they work. I guess the
difference is between the temperature we feel and the actual temperature.

Some people find that the small "personal" evaporative coolers do work a
bit - the evaporation effect will cool the air they blow out at you a
little bit - and the amount of moisture they contribute to a room is
relatively small once it has a chance to diffuse within the room (they
only consume a cup of water a day). The larger "room sized" evaporative
coolers are on a hiding to nothing in our climate however.

Please correct me if I'm wrong. High humidity when its hot means that my
sweat doesn't evaporate as quickly/easily so I feel hot. Surely then
reducing the humidity is the way to go as this will allow my sweat to
evaporate more easily.

This is correct.

So - would a dehumidifier help to reduce how hot I feel? I've never seen

Chances are it would help your bodies natural cooling mechanism to work
more effectively. There would also be a side effect benefit in that they
presumably include a fan to move air through them which would help keep
the air moving in the room a bit.

In scientific terms however the de-humidifier is likely to raise the
room temperature by an amount equal to its power dissipation. This will
offset or even counteract the benefits.

them advertised as being able to do this - whereas things which humidify
(evaporative coolers) seem to claim they do.

They can claim to reduce the temperature since if you measure the air
output temp it will be colder since you have extracted some heat from it
to help vaporise the water. Alas its a bit like wind chill - the
thermometer does not tell the whole story!

Basically I'm confused about it and just want a (reasonably) cheap option
(also preferable movable between living room + bedroom) to cool us down.
Fans may be the best option (price wise) I know - but I'm trying to think of
other options too.

All the usual things... insulation, increasing shade - plants, trees,
creepers etc. Reducing solar radiation absorbtion with blinds or solar
window film, forced air ventilation (fans etc). Turning off heat sources.

Incidentally, what's the sort of price I should expect for a reasonable
split air-conditioner? I'd love to be able to permanently install one for
the living room - however it then seems a waste as I can't use it in the
bedroom (unless it managed to cool the whole house down!).

You can get portable split units - you hang the condenser outside the
window and its connected to the air handler inside via an "umbilical".
Not that cheap mind:

http://www.coolbuys.co.uk/mall/AirCo...uct-752461.stm




--
Cheers,

John.

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IMM wrote:

"Based on our findings, we recommend that radiant barrier systems be
considered for homes with shingle roofs both in FPC's Home Energy
Improvement program as well as emphasized in FPC's new homes program where
installations would be most cost effective."

That would be partially IR translucent wooden shingles then... not that
common on UK houses!


--
Cheers,

John.

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Mary Fisher wrote:


- Switch off everything electrical you can (a TV left on can dissipate

several

hundred watts in heat.

Dubious. A 100W lightbulb won't generate 100 watts of heat, neither
will a 100W heater for that matter.


The details are unimportant. The principle is right.

I know what you're saying, but incorrect statistics lead to incorrect
"solutions".

--
jc

On Thu, 7 Aug 2003 21:28:29 +0100, "IMM" wrote:


"Julian Fowler" wrote in message
.. .
On Thu, 7 Aug 2003 20:08:51 +0100, "IMM" wrote:


"Julian Fowler" wrote in message

snip

read the site some more

... so that I can extract the words that support your misunderstanding
of these particular research results and ignore all the rest? I have
only glanced at the main body of the paper; however, if (as you seem
to be suggesting) that contains important information that is not
covered in the executive summary then I suggest that this is a very
poorly written paper (which could suggest that the underlying research
ain't too hot either).

So that means you haven't looked all over the institutions site then.

So that means you don't understand what a citation is then.

Julian

--
Julian Fowler
julian (at) bellevue-barn (dot) org (dot) uk

he has got a point (!) Tiles will absorb radient energy from the sun and
re-radiate some of that down into the attic space. Lining the inside of the
roof with tinfoil would reflect some of this back, and reduce convection
currents.

Whether it would make a noticable difference to the rest of the house is
another matter!

Since I am sick of renovating my kitchen I might try an experiment this
weekend

So if you wrap your hand in foil and stuff it in a BBQ the foil will act as
a heat barrier- let me know how you get on at A&E ;-

Hi Baxter Basics
In . net you wrote:

So if you wrap your hand in foil and stuff it in a BBQ the foil will act as
a heat barrier

No, because the foil is an extremely good conductor of heat.
It is also extremely good at blocking radiant heat. So if you created a
glove of foil /that did not touch your skin/ then you could stuff your hand
in a BBQ.

--
Fishter
unhook to email me | http://www.fishter.org.uk/

"Baxter Basics" wrote in message
. net...
he has got a point (!) Tiles will absorb radient energy from the sun and
re-radiate some of that down into the attic space. Lining the inside of
the
roof with tinfoil would reflect some of this back, and reduce convection
currents.

Whether it would make a noticable difference to the rest of the house is
another matter!

Since I am sick of renovating my kitchen I might try an experiment this
weekend


Compared to the amount of heat that is transferred into the house by direct
thermal conduction from the (hot) tiles to the air and hence induced thermal
convection, the amount introduced by radiant energy is small at these
temperatures.

You'll be much better off insulating between the rafters. That will stop
the loft space heating up to such a high temperature, and hence reduce
direct thermal conduction to the house below.

cheers
Richard

--
Richard Sampson

email me at
richard at olifant d-ot co do-t uk