[MontaniSemperLiberi]

It was done for a while in the 70s, when energy costs were high in relative terms (for example, see SWEPCO, which has been around since 1933). When energy costs dropped, the market fell for such products, but it does make sense under the right market conditions.

I'm sure aluminum roofs have been around for a long time but they act as much as a barrier to heat transfer since they act as a shield from the heat coming from the inside. Note that there are a lot of metal roofs yet many of them are painted. Aluminum tank trailers work because the fuel is in direct conductive contact with the metal tank.

[Gondring]

Did you not click on the other products on the left, such as the titanium-dioxide-based ones?