What Insulation to use for a Sauna Build - safe and efficient (and what to Avoid ! )

What insulation you should use for your sauna build. Full install video also posted.
Product list below.

Insulation:
https://www.homedepot.com/p/ROCKWOOL-...

you can use this thicker one for ceiling:
https://www.homedepot.com/p/ROCKWOOL-...

Insulation Knife:
https://www.homedepot.com/p/Grip-Rite...

Stapler: (manual)
https://www.homedepot.com/p/Arrow-Arr...
or battery:
https://www.homedepot.com/p/RYOBI-ONE...

Staples:
https://www.homedepot.com/p/Arrow-T50...

or stainless steel:
https://www.homedepot.com/p/Arrow-T50...

Aluminum Tape:
https://www.homedepot.com/p/Nashua-Ta...

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