Is there a way to measure or predict how much a 10.5 microns Aluminum foil attenuates EMF radiation?
The standard thickness of PCB copper foil, at 1 ounce/foot^2 weight, is 35 microns or 1.4 mils.

The SkinDepth frequency, at which you can expect 1 Neper (8.6 dB) attenuation, for that copper foil, is about 4 MHz. To achieve 2 nepers (17dB), you need 4*4 = 16MHz. To achieve 3 nepers (28dB), you need 4 * (3*3) = 36MHz. To achieve 4 nepers (34 dB), you need 4 * (4*4) = 64 MHz.

If you reduce the thickness of copper foil by 10:1, the frequency increases by 3.16:1.

If you reduce the conductivity, from copper to aluminum, the frequency also rises.

At low frequencies, your attenuation will be greatly reduced. At 60Hz, the skindepth of copper is 8 milliMeters, thus power station bus bars (perhaps water cooled) need be only 1cm thick tubes, because the 60Hz currents will only weakly penetrate further than 8mm.

This means your 35 micron foils ( or 0.035 milliMeters) are useless for EMI at 60Hz rates.

My view is: the chopping energy of switching power supplies will easily penetrate copper foil. The ringing energy due to parasitics will be somewhat attenuated.

The marvelous thing about the attenuation of 10 skin depths is: this is 86dB attenuation.

To have 10 skin depths, you need to be at 400 MHz.

Thus standard PCB foil does a fine job of attenuating MicroController clocks and the edges.

You can  use multiple layers of foil.

Will you define the frequency of the "EMI" ?

And how much attenuation you need, in dB and in Nepers?

Can you use copper foil, or aluminum foil (to which you cannot solder), in a Faraday Shield? Yes, but you have to decide what is "Ground" so the charge surging into the Shield is shunted to some location that will not upset the circuit inside the Shield. Can you do that?