Cool an attic during hot weather

[Christophe]

Rolalalal...zyzy is lost again...

We know that thin insulators are not a panacea compared to a classic insulator, all I'm saying is that it works well against IR radiation...We've known that for years!

heating-insulation/tests-tests-and-performance-of-thin-insulation-thermo-reflectors-t3069.html

[izentrop]

I don't know what it's worth, I have a bit the same problem (without the mess in the attic ) and I was thinking of putting some reflective insulation on the slopes to contain the radiation from the tiles, and adding insulation thickness to the attic floor.
All this being interesting in summer and winter.

Ahmed's idea of ​​ventilation seems to me three interesting too, I would have seen it mechanical. a fan consumes 60W.
At least it handles the emergency. Now you need a good opening for fresh air, which I don't have.
The evacuation is done by the tiles but the best would be an opening opposite the arrival.
And in addition maybe a fribro roof is more airtight?
A diameter of 10cm even with a fan seems insufficient for an attic and that's all I currently have.

So there, all wrong, the outside air at 30° will end up above and under the glass wool placed on the floor... efficiency 0
And for the reflective insulation it is also an idea received from advertisers and sensationalist articles, see my previous link

I see people opening their roof windows when it's hot, which has the opposite effect.
At first the draft is refreshing, but very quickly by convection, the cooler air from inside is replaced by warm outside air.

[sicetaitsimple]

And if not the shot of the free fleet to moisten the roof?

About ten years ago, Remundo had created a thread where he explained his project to cool PV panels placed on the roof by running water.
There is certainly some interesting information to retrieve from a system design point of view.

solar-photovoltaic / optimizations-autonomous photovoltaic-with-liquids opal-t11091.html

[Christophe]

I thought about it too...but it's not "gratos"...

[izentrop]

Rolalalal...zyzy is lost again...

We know that thin insulators are not a panacea compared to a classic insulator, all I'm saying is that it works well against IR radiation...We've known that for years!
heating-insulation/tests-tests-and-performance-of-thin-insulation-thermo-reflectors-t3069.html

Yeah! comments from private individuals do not stand up to CSTB measures and expert advice

Reflecting IR radiation is useful outside and not under the roof where you benefit from the greenhouse effect as for the interior blind of a roof window.

[Christophe]

But what are you talking about?

Are you talking about this report that I published in 2010? https://www.econologie.com/file/habitat ... _mince.pdf

Technical study and comparative tests on thin insulators: initial thermal performance of Thin Reflective Products (PMR)

The BBRI as well as other organizations, including the public authorities, are today confronted with a growing number of requests for information concerning products commonly called “thin reflective products” (PMR). The public authorities, partners in this study, would like clarifications as to the characteristics of this type of product, in particular with a view to the application of the thermal regulations in force in each Region of the country.

One of the BBRI's missions being to carry out scientific and technological research making it possible to better inform the construction sector of the evolution of materials and installation techniques, the BBRI has been led to propose a study on the performance thermals of PRMs.

https://www.econologie.com/etude-techni ... ts-minces/

Now buy yourself a survival blanket and see how well it works with IR...

[Ahmed]

Concerning thin insulators, I also doubt their major interest in the case that interests us here, but ventilation remains, when possible, a good basis. Indeed, under the roof the intense radiation of the tiles raises the temperature well above that of the ambient air. I also saw it at my expense by finishing an attic insulation: I dehydrated in a very short time, when the sun was hotter, at the end of the morning...

[izentrop]

In Gegyx I would rather recommend that https://www.cahiers-techniques-batiment ... ture.59202

[Christophe]

Uh, you guys ever had a survival blanket in your hands?

In this case, the concern is their placement! Ideally it should be directly under the blanket...

[Christophe]

In Gegyx I would rather recommend that https://www.cahiers-techniques-batiment ... ture.59202

Yeah and then you claim thin insulators don't work? Do you know you're funny?

This painting, with a lot of perlinpinpin powder in it, see heating-insulation/insulating-paint-genre-thermacote-info-ou-intox-t10962.html is also certainly as expensive to make as a solar installation!

We can also plant trees or ivy!