The instructions on their website for the board from 2015 state to use unmodified thinset for installling the usg 5 band over the seams but no mention of what type of thinset for the tiles so which is best type of thinset in this situation for foam board with large format tiles.
Best thinset for ceiling tile.
A little extra thinset beneath a tile is completely acceptable not enough thinset beneath the tile is not acceptable.
Porcelain tile mortar is formulated for installations over concrete and backerboard.
You do not need a 75 bag of non sag thinset to tile a ceiling.
Gray thinset mortar is typically used with ceramic and porcelain floor tiles.
This helps to prevent tiles from cracking.
Superior bonding of porcelain to concrete backerboard and cement self leveling underlayment.
Before you start hanging head bashers ceiling tile you should as always have the substrate properly prepared.
I could not tell from your flow chart.
Since thinset tile mortar may crack you may wish to mix it with a special latex additive to increase its strength.
While it is easier to obtain complete coverage with a u notched you must also use a larger u notched trowel to achieve the same bed thickness beneath the installed tile.
Excellent for glass tile and radiant heating system installations use for interior or exterior.
Thinset with small amounts of latex added are primarily used for large format tiles and stone tiles to help absorb flex from floors and walls.
Mix the thinset with a mixer rather than by hand let it slake for five minutes and then mix it again.
Additionally thinset comes in either unmodified or modified versions.
Inorganic and composed of materials mined from the earth thinset is inexpensive and can be purchased either in wet pre mixed or dry powdery form.
Unmodified thinset is composed of portland cement sand and water retention agents.
They do not always need to be waterproof.
You can accomplish the same with the 15 bag of regular modified thinset.
By applying the tile onto the ceiling like this with a 1 2 bead of thinset around the perimeter of the tile it will create a vacuum between the tile and the ceiling when applied.
It s also expensive stuff.
Square notched is a personal preference.
Non sag thinset is basically just thinset that is sticky it s great stuff.