odor adsorption

Ancient Egyptians used natural gypsum mortar between limestone blocks at Giza — 4,500 years ago. They chose it for a reason that still matters today. The porous microstructure of calcium sulfate absorbs small movements and humidity fluctuations, buffering stress at every joint. Modern gypsum board works on exactly the same principle. That porous structure lets walls breathe, absorbing moisture when humidity rises and releasing it when the air dries. It is gypsum’s greatest strength. But those same pores do not discriminate. Tobacco compounds, cooking vapors, ammonia-based biological residues — they enter the same way water vapor does, then adsorb to the pore walls and stay. The ancient builders never faced this problem. The desert air gave them only moisture to manage. We are not that fortunate.