We use Australian #1 brand for heat insulation.
The whole rooftop ( 315 meters square) use Aircell Retroshield product.
Here is the general information:
Retroshield ™ (IP Australia Patent Pending No. 38983/01) features two opposing faces of high polish aluminium foil surfaces separated by a fire-retardant polyethylene cell structure. Retroshield ™ is a clean, safe, fibre-free insulation designed to replace conventional fibre based batt and building blanket insulation in commercial and residential buildings. Retroshield™ is installed into the walls, roofs, ceilings and floors as a vapour barrier and insulation blanket all in one. AIR-CELL Retroshield ™ Retroshield ™ is manufactured without the use of toxic or reactive adhesives. This distinctive feature means that Retroshield ™ is extremely durable over time, as there are no foreign properties to react and cause product degradation over its extended life.(http://www.solartek.co.id/Retroshield_Product.aspx)Special thanks to Mr. Iwan from Solartek Indonesia for these pictures.The house was in construction.

Applied on the whole rooftop surface.



After installation, the indoor temperature is 29,2 Degrees Celcius while the outdoor is more than 35 Degrees Celcius. (The weather in Pantai Indah Kapuk area is always hot, especially during mid day).
Some additional information in Indonesian:Di kota-kota besar atap rumah perlu diberi penyekat yang mampu menepis panas matahari. Air Cell adalah salah satu produk insulasi atau penghambat panas itu. Produk berupa lapisan alumunium dan lapisan berkantong udara ini, bisa dipasang di bawah genteng atau di dinding rumah agar ruangan lebih sejuk.
Produk Australia dengan ketebalan 8 mm ini dilapisi alumunium foil 6,5 mikron di bagian atas, lalu polyethilene, dan plastik yang memiliki rongga di bagian tengah (buble). "Produk terdiri dari tiga jenis, air cell retroshield, retroshield E/MP dan utility. Bahannya sama, yang beda kualitas dan ketebalannya," kata Irwan Wihardja, Marketing PT Solartek, distributor Air Cell di Indonesia.
Air cell retroshield paling tebal dan tingkat kemurnian alumunium foilnya tinggi (99,4 persen). Selain itu tahan sobek (mampu menahan beban manusia hingga dua orang). Air Cell diklaim mampu menurunkan suhu 8-12 derajat celcius. Beratnya hanya 381 gram/m2. Pemasangan mudah. Untuk atap rumah yang belum selesai, insulasi bisa dipasang di atas kaso dan di bawah reng.
(http://www.housing-estate.com/index.php?option=com_content&task=view&id=189&Itemid=72)