Air-seal construction is the engineering principle behind the moisture resistance that distinguishes a high-protection metal burial vault from a basic steel or concrete enclosure. The design relies on the vault dome's geometry. When the dome seats over the base and the assembled unit is placed in the ground, a pocket of air becomes trapped inside. As the water table rises around the vault exterior, that trapped air pushes outward against the incoming water pressure. The result is a passive seal that does not depend on adhesive gaskets or chemical bonding compounds to keep the interior dry, and one that does not degrade the way organic sealants can over extended burial timelines.
CMV Fabrication builds air-seal construction into its custom metal vaults as a standard engineering feature. Every finished unit is water-tested at the facility before it ships, and the test confirms that the air-seal mechanism is functioning as designed under pressure conditions that replicate what the vault will encounter below ground. For funeral directors comparing metal vault options for their client families, the ability to point to a tested, verified seal on each individual vault is a meaningful differentiator. CMV Fabrication provides that verification as part of the manufacturing process on every custom metal vault it produces.
