DIY builders and masons struggle to source or correctly formulate Type O mortar for restoration work

Homeowners and DIY enthusiasts attempting masonry repairs, particularly on older structures, cannot easily obtain Type O mortar (a low-strength, high-flexibility mortar used for historic preservation) or lack clear guidance on how to mix it correctly themselves. Commercial suppliers often don't stock it, and incorrect mortar selection causes structural damage to historic buildings and failed repairs that require expensive professional remediation.