Reflective materials
Reflective materials can be used in a lot of settings to improve the use of light and also harness the power of the sun for cooking and other high-energy processes -- such as air drying. At the same time the same energy that creates light and illumination, also can be reflected away from a building to prevent passive increases in temperature because of the Urban heat island effect.
Reflective materials for building things
[edit | edit source]Reflective materials can be part of building appropriate technologies that center cooking, energy use or lighting:
Reflective surfaces for cooling buildings
[edit | edit source]Reflective material can also help with cooling buildings by reflecting sunlight away from. A "cool roof" uses a reflective coating, often white paint, so the roof absorbs less of the sun's heat. In Kerail, an informal settlement in Dhaka, Bangladesh, reflective roof paint lowered average indoor temperatures by 3.5 °C, and by up to 7.7 °C at peak. In low-cost housing in Jakarta, Indonesia, coated roofs kept rooms 2–2.9 °C cooler on days above 34 °C.[1] Because the coating is cheap and uses no electricity, it is one of the most accessible ways to reduce heat stress for people who cannot afford air conditioning.
Examples of low cost reflective materials
[edit | edit source]This table compares aspects of different types of reflecting materials.
| Material | Reflectivity | Weight | Internet price quote | Advantages | Disadvantages |
|---|---|---|---|---|---|
| Polished Anodized Aluminum | ~95% | Light | ~$7/square foot | Reflective, lightweight, can be salvaged, structurally durable, easily flexed and shaped | Easily scratched, not super cheap |
| Mylar | >98% | Super light | $30 for a 4'x'50 roll | Super reflective, super light, super cheap | Not good at standing up to the elements, forms 'bubbles' if glue starts to give, requires a rigid backing |
| Aluminum Foil | 88% on bright side | Super light | $3.29 for 1.5'x70' roll | Extremely cheap and widely available | Not so reflective, corrodes when mixed with acidic juices, structurally weak, would only last one or 2 sessions |
| Can lids | 70-80% (my estimate) | Light | FREE | Widely Available, effective, salvageable, did I mention free?! | Not super reflective, non-uniform shape is labor intensive to use |
| Acrylic Mirror | 99% | Medium/Heavy | $78 for 1'x4' plane | Very reflective, nearly unbreakable | Comes in plane, likely very difficult to fit to parabola and still maintain reflectivity, super expensive |
| Glass Mirror | 99% | Heavy | Prices vary heavily depending on country. 2mm is cheaper but harder to find (e.g. $7.80 per SQF in France, Castorama). 3mm and 4mm are more common, but more expensive. | Super reflective, widely available new in glass and hardware shops, also salvagable. Durable. | Can be ordered new, cut to size. Broken mirror can be used in certain designs. |
| Astro-foil | 76% | Light | $37 for 1'x50' roll | Relatively strong | Not so relective |
See also
[edit | edit source]| License | CC-BY-SA-3.0 |
|---|---|
| Cite as | Zachary A Estela, Alex S., Megan Moore (2007–2026). "Reflective materials". Appropedia. Retrieved October 29, 2026. |
- ↑ Sustainable Energy for All. "The power of passive cooling solutions in Bangladesh and Indonesia." 2021. https://www.seforall.org/stories-of-success/the-power-of-passive-solutions-in-bangladesh-and-indonesia via the Climate Insights Directory