Mirror tiles on an outside wall

[Addison]

I might put mirror tiles on an outside wall to reflect and keep heat indoors.
We did this as Boy Scouts with aluminum foil to reflect the fire’s heat into the tent.

Is this effective?

[home improvement guy]

Mirrors will not function the same as aluminum foil by the fire. Mirrors reflect visible light but not heat energy. Bright aluminum foil reflects heat and light.

If you want mirrors and more wall insulation, try stapling aluminum foil loosely to the wall.

Place shallow furring strips over it and attach the mirror tiles to the strips.

This creates the necessary air space to make the foil’s heat-reflective properties effective.