Foil insulation and metal strips are great for the attic sidewalls and disastrous to the TV signal. Make sure that when antenna install happens the installers make your antenna stand in a position that the path between TV transmitters and antenna is not obstructed by any of these materials.
Facing signal loss or installing antenna outside?
By this time you have clearly understood that attic antenna install is not going to be easy given the obstructing quality of the building materials. You can consider mounting your antenna above the roof line as this will improve the signal quality to a great extent.
This level of elevation will also put the antenna outside the range of material obstructions. Weak signals and long distance signals will be benefitted greatly if the antenna installation is done above the roof line.
Selecting the right equipment for TV antenna install
Don’t expect your TV antenna to work as well inside your attic as outside. There will always be some obstructing factor inside the attic so professional advice is a must before you choose antenna install equipment.
A mono amplifier or a distribution amplifier is likely to favorably benefit the antenna installations The signal amplification effects will nullify the obstruction effects of the attic building material. This of course depends on the availability of a suitable electrical outlet in your attic.
If you feel that your attic space cannot accommodate a larger antenna then its best to go outside for your antenna install.