Cooling tips

[MNW67]

Of course, which was why I mentioned that, plus human activity, and use of appliances in the home, in my post #351. However, even without those effects, no windows, no humans, no appliances running - heat and cold will still seep through the insulation, no matter 'how robust' the insulation installed, it will, without any doubt seep through - basic physics, which most learn, as five-year-olds.

Nobody is disputing the basic science. My interest is in applying the basic science to get the best design.

 

[motorbiking]

That is just another stupid gotcha question.

The point is that 10mm of insulation can be robustly installed just as well as 100mm. Its meaningless.

The only thing that matters is thermal conductivity. if you can get your head around why insulation conducts heat, no matter how robustly its installed, you will get further than Nosenout who seems convinced that a robustly insulated wall stops all of it.

Nobody is disputing the basic science. My interest is in applying the basic science to get the best design.

Not true - Nosenout doesn't understand it. As evidenced by this comment:

I asked you to demonstrate heat transfer through a robustly insulated cavity wall, during a regular hot day scenario. I'd like to see this 'inevitable' heat through the insulation you blathered about.

Insulation does not stop thermal transfer, unless its U value is zero.

 

[MNW67]

I know, let's call it a U value

You can have two external walls with exactly the same U value. But if all the insulation is on the inside of the thermal mass that will give a very different lived experience to if all the insulation is on the outside of the thermal mass. It is about applying the science as well as understanding it.

 

[motorbiking]

You can have two external walls with exactly the same U value. But if all the insulation is on the inside of the thermal mass that will give a very different lived experience to if all the insulation is on the outside of the thermal mass. It is about applying the science as well as understanding it.

The external insulation prevents solar gain more effectively, it's got nothing to do with the insulation's U value. Painting the wall white adds zero in terms of thermal resistance. It has a massive difference to solar gain.

 

[Harry Bloomfield]

Definition of robustly adverb from the Oxford Advanced Learner's Dictionary

robustly​

adverb

/rəʊˈbʌstli/


/rəʊˈbʌstli/

1. in a strong and healthy way The plants grew robustly.
   Want to learn more?
   
   Find out which words work together and produce more natural-sounding English with the Oxford Collocations Dictionary app. Try it for free as part of the Oxford Advanced Learner’s Dictionary app.
   
   
2. in a strong way that is not likely to break or fail synonym sturdily (1)
   • The furniture was robustly constructed.
3. in a strong or determined way that shows you are sure about what you are doing or saying
   • They defended their policies robustly.

 

[MNW67]

The point is that 10mm of insulation can be robustly installed just as well as 100mm. Its meaningless.

The only thing that matters is thermal conductivity. if you can get you head around why insulation conducts heat, no matter how robustly its installed, you will get further than Nosenout who seems convinced that a robustly insulated wall stops all of it.

Why do you always have to be such an insulting arsehole.

There have been several times when I have been shocked at your lack of understanding of simple legal principles. And I have gently baby walked you through them. Without you even knowing I was doing it.

I fully understand the underlying science. I have almost certainly studied it to a much higher level than you. Which is why I don't write meaningless sentences such as:

Did you understand why a window has a one way capability when it comes to solar radiation?

 

[motorbiking]

Why do you always have to be such an insulting arsehole.

There have been several times when I have been shocked at your lack of understanding of simple legal principles. And I have gently baby walked you through them. Without you even knowing I was doing it.

I fully understand the underlying science. I have almost certainly studied it to a much higher level than you. Which is why I don't write meaningless sentences such as:

Sure you have

 

[StephenStephen]

You wanted graphs? This is my home's temperature graphs for the past 24 hours. The yellow represents the indoor temperature, the blue the outdoor.

My too hot weather regime, is one of closing windows, drawing blinds to limit solar gain, just having a fly screened back door open for ventilation.

My home is reasonably well insulated, hence the yellow line is fairly flat, but it does drift slowly up, as the outdoor temperature increases. Come bedtime, at around 11pm, the windows are opened to vent the heat gain (despite the insulation) from the day/human activity/use of appliances.

You will note - insulation can delay temperature rises, and falls, but it can only delay the inevitable, and smooth out the average.

View attachment 385260

I really think that it's both inaccurate and unhelpful to keep using the term 'inevitable'.

If there is sufficient insulation of all kinds, then the indoor temperature rising to the outdoor temperature is only inevitable if the outdoor temperature remains constant for long enough.

Which it simply doesn't in the UK.

So it is not inevitable.

 

[MNW67]

Definition of robustly adverb from the Oxford Advanced Learner's Dictionary

As I said, it is not a word I would have chosen myself. But I think noseall simply means well insulated when he writes robustly insulated,

 

[motorbiking]

As I said, it is not a word I would have chosen myself. But I think noseall simply means well insulated when he writes robustly insulated,

Actually to be fair, he doesn't. He means well installed.

 

[noseall]

That I did, more than adequately, with coloured pictures. The inevitable heat rise, shows in the yellow line, but only for those who would see. Should I try crayons next?

Nonsense. You show me a warm inside wall surface due to external sunshine with a robustly insulated cavity wall and I'll show youa flying pig.

 

[Harry Bloomfield]

Nobody is disputing the basic science. My interest is in applying the basic science to get the best design.

There is no best design - it is a compromise of cost, versus U value. The more you pay for insulation, the better it performs as insulation, but no matter how much you pay, it can only delay the inevitable flow of outdoor heat, or cold to the interior.

It's also a balancing act - add too much insulation, not enough ventilation, and even in cold weather the solar gain/human occupation/appliance use - can cause the interior to overheat.

 

[StephenStephen]

I'm wondering if there's a misunderstanding here - whilst of course it's not possible to reduce heat transfer to zero (entropy, the heat death of the universe etc), can it be argued that, in the UK, house wall insulation can be sufficiently effective so as to make the heat transfer negligible, and therefore, in a practical sense, in terms of designbuild and use, non-existent.
(Similar to the way that feedback amplifier calculations make the technically false assumption that there is no feedback, get produce and accurate enough result)

 

[motorbiking]

There is no best design - it is a compromise of cost, versus U value. The more you pay for insulation, the better it performs as insulation, but no matter how much you pay, it can only delay the inevitable flow of outdoor heat, or cold to the interior.

It's also a balancing act - add too much insulation, not enough ventilation, and even in cold weather the solar gain/human occupation/appliance use - can cause the interior to overheat.

some would say at <.20 we have already crossed the line where energy efficiency gains aren't worth the problems caused by excessive insulation.

 

[motorbiking]

I'm wondering if there's a misunderstanding here - whilst of course it's not possible to reduce heat transfer to zero (entropy, the heat death of the universe etc), can it be argued that, in the UK, house wall insulation can be sufficiently effective so as to make the heat transfer negligible, and therefore, in a practical sense, in terms of designbuild and use, non-existent.
(Similar to the way that feedback amplifier calculations make the technically false assumption that there is no feedback, get produce and accurate enough result)

Going back to the original argument the issue and argument was more to do with the impact of windows, which most people would want in their home.

Solar energy passes through the window, heats up objects inside and cannot pass back out, due to the insulation. That seemed to be the basis of the argument.