Reynolds Metals

Does putting aluminium foil on a window keep rooms cooler?

If it keeps the heat out, which side is best to face the sun? If the shiny side is best could it start any fire outside?

Public Comments

1. The shiny side would be best. I seriously doubt that it would start any fires outside. You'd need a concentrated beam of light (like through a magnifying glass) to start a fire.
2. It will only reflect the heat coming in from the sun, which will drop the temperature down somewhat.Then I recommend to circulate the air by way of fans this will cool down the house enormously.Keep windows and doors closed.
3. I believe people put up aluminum foil to keep out the light, not heat. But keeping out the heat would be a beneficial bi-product of keeping out the light. When you cook with aluminum foil on something like a turkey it isn't to keep out the heat (you could just lower the temp of the oven instead of covering it with alum foil) but to keep it from browning. No fire danger from shiny side out.