What Kind of Mortar to Use for Glass Block Windows?

Do not use regular brick mortar for glass block. You will need to use a premixed glass block mortar. Why can't you just use plain old mortar? Because brick mortar has high water content, and this water gets "pulled away" with capillary action by the porous brick. Glass block is not porous and so will not pull the water away. Glass block mortar is drier than brick mortar.

Am I Right About Glass Block Mortar? Wrong?

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