Reflective Foil: Quality Comparison?

[carlyai]

I'm nearly at the stage of putting the insulation up, but I can't find where to buy the Cool Guard Woven Cloth. From the excellent comparison article in this forum, this would seem to be the best insulation for me. The article is a little dated and there may be newer brands with excellent insulation properties, but if so can someone enlighten me or tell me where I can find the Cool Guard product on the internet or where i can buy it in Isaan?

[IMHO]

Just thinking... it seems to me that any insulation would be pointless in the attic area here in LOS. Reflective foil with/without insulation would seem to be the best way to reflect heat radiation. I wonder if just laying down Al foil - shiny side up - would be a good idea?

Not sure exactly what you mean by "al foil" - I read that as being "aluminum foil" - i.e. the stuff you use in the kitchen? If that's what you're suggesting, I wonder how effective it could be given the way it conducts heat? Not saying it wouldn't work as a radiant barrier, but assuming it's not going to be as effective as the foil backed paper normally used, which has far less heat conductivity. I can also foresee some real challenges getting a continuous barrier as it tears so easily.

As for insulation being pointless, I don't see how you arrived at that conclusion - sunlight is always hotter than ambient air temps, so anything that reflects or insulates against the heat of the sun getting into your house has to be a good thing, no?

[IMHO]

I'm nearly at the stage of putting the insulation up, but I can't find where to buy the Cool Guard Woven Cloth. From the excellent comparison article in this forum, this would seem to be the best insulation for me. The article is a little dated and there may be newer brands with excellent insulation properties, but if so can someone enlighten me or tell me where I can find the Cool Guard product on the internet or where i can buy it in Isaan?

Have you visited a Global House store? That's where the OP found it, if I read his post correctly.

[bankruatsteve]

I'm just thinking that the primary source of attic heat in these parts is from the UV radiation and reflecting that as much as possible will keep whatever is on the other side cooler. Insulation is double edged: it helps to reduce thermal transfer but that means it will keep heat "in" as much as "out".

Yah - Al = Aluminum/Aluminium. I realize rolling out the cooking stuff might be impossible to maintain stability but maybe worth a try. (?)

Edited May 22, 2014 by bankruatsteve

[cooked]

Great topic. I wonder if it will help to place roof insulation on top of ceiling, but no under roof tiles (Like laying a big carpet).

That's the way I am going to go, 15cm of insulation with foil on both sides. The heat in our roof space is insufferable in summer and it radiates down all night long. I will be fixing vents to ensure air circulation

The problem is that the ceiling is held up with countless bits of wire which will probably all have to be replaced. Some people even install a fan up there and whirligigs, but I think this is going over the top. I really don't fancy taking the roof off, fixing the reflective foil to the purloins, fixing wood to that lot and then putting the roof back.

[IMHO]

I'm just thinking that the primary source of attic heat in these parts is from the UV radiation and reflecting that as much as possible will keep whatever is on the other side cooler. Insulation is double edged: it helps to reduce thermal transfer but that means it will keep heat "in" as much as "out".

Yah - Al = Aluminum/Aluminium. I realize rolling out the cooking stuff might be impossible to maintain stability but maybe worth a try. (?)

Right, the primary source of heat is solar radiation on exposed surfaces like roof tiles, walls, and windows/doors (it's not just UV BTW, heat is also transferred by visible light and IR).

Your first line of defence against this is always going to be reflection - i.e. inhibit it from exciting atoms (and thus making the surface hot) in the first place. The second line of defence is to inhibit the conductivity of heat.

In the case of normal reflective foil barriers, they are actually doing a bit of both.

Aluminum foil only will work as a reflector, but not 100% of course, so some of it will still get hot and it will conduct that heat pretty effectively into the crawl space - by how much I don't know, but certainly at least more so than the foil backed paper commonly in use.

As en experiment, get a piece of aluminum foil and a piece of roofing foil of the same size, then light a match on one side of them and judge how much heat you feel getting through to the other side from each type

[bankruatsteve]

The match 'experiment' seems more relevant to heat conduction vs. radiation so here's what I tried: I put Al foil covering the rack in my toaster over and set to top element only. Using my MM temp. probe, the starting temp was 32C both top and bottom. After about 1 min. with top element on, I quickly measured bottom space (33+) and then measured the top needing to wait about 10 sec for it to stop at about 44C. Measured the bottom again (needing to wait for it to stop again) and got 34C. This isn't exactly an experiment b/c I didn't repeat it, couldn't measure both spaces at the same time, had to open the door to do the measurement, and didn't try different types of material. But, I think it does illustrate that reflecting heat radiation is probably much more effective than insulating the conduction for places like attic space.

[Naam]

reflecting heat radiation is probably much more effective than insulating the conduction for places like attic space

[Naam]

Your first line of defence against this is always going to be reflection

[Naam]

i was shown the nonsense of spraying foam underneath the tiles for attic insulation purpose a decade ago and couldn't help laughing out loudly.

[oilreg]

from what I researched so far it's like some poster said already, PA foam is the best but that starts at 400+ per set, in a similar thread at cool that house a guy figured that the very cheapest foil for 1200 the for 70 running meters has the same effect then the really expensive ones, search there for a thread, silver foil does work to check it out yourself

Sent from my GT-N8000 using Tapatalk

[crs]

Has anyone got a number for Cool Guard? (Might be on the packaging.) Can't find a website for the manufacturer and want to call to see if they have a seller in Chiang Rai...

Edited September 15, 2015 by crs

[eyecatcher]

Has anyone got a number for Cool Guard? (Might be on the packaging.) Can't find a website for the manufacturer and want to call to see if they have a seller in Chiang Rai...

I am using this coolguard foil. About a thousand rolls in Global. I think 1490bt for a 60m roll. No phone number on the label though.

[crs]

Thanks. It's the woven blue labelled one I want - will have to get to a Global sometime...

[kamalabob2]

I bought quite a bit of CPAC Ultra Kool 2" insulation from the Surin Home Mart in 2007. Other than birds making it a temporary home (then I put Stop Bird repellent and solved that problem) it has worked well for me. For a new modest home in a Buriram Province village I e-mailed to a technical person at Diamond Building products. I was also interested in how water might be blocked (although not the first line of defense). This is the answer I received from Diamond Building Products.

Please, let me answer your question instead of Ms. Pattaraporn.

Your question is what is the middle layer of your four rolls of radiant barrier?

For this model “Radiant barrier, Single-sided” the middle layer is a PLASTIC which is the only one model that we have.

And another three models are Craft Paper that follows the government policy.

So, you can explain to your customers that this model is suitable for them.

Lastly, feel free to contact me if you have any questions.

Thank you and have a good day.

Best regards,

Mr. Todsaporn Wongnakarin

Product Officer

E-mail: [email protected]

Website: www.dbp.co.th