Why Use a Vault?
My brother and I are having a disagreement as to whether or not to use a vault for my mother. He states that studies have shown that the vault, by trapping the decomposition gases, will speed "everything turning to mush." Whereas I feel that a vault would be desirable to protect the casket. Can you give me some, preferably scientific, information as to why we should use a vault?
A "Grave Liner" the predecessor to the vaults we use today was designed for one purpose, to hold the integrity of the grave. To re-pack the dirt back into the grave so that it does not settle you need some sort of compactor and something solid to compact the dirt against. This process was designed so that the cemetery would not have to come back and refill the grave after a burial.
Today we still use concrete grave liners as well as vaults. All vaults do not seal, some use a trapped air principal to keep water out. My belief is that the best vault would be made of concrete with a liner and be sealed air and water tight. The liner keeps water from passing through into the inner chamber where the casket is, as well as strengthen the concrete against cracking. The primary job of this sort of vault is to seal air tight and water tight and protect the casket and person inside.
"Preferably Scientific Information": There is no such thing as decomposition gas. Decomposition, as we are speaking about it (biological not chemical) is caused by bacteria, enzymes and light. It may also be a product of cells that have ceased to receive outside nutrition literally cannibalizing the cells around them for food and oxygen. Decomposition is greatly retarded by the embalming procedure. Having said that the "vault" has no positive or negative effect on decomposition. The "vault" may protect the body from moisture and elements in the soil but this is not the same as decomposition.
I must conclude with the fact that your argument may be a moot point. More and more cemeteries are requiring a grave liner or vault for burial. Check with the funeral home you plan to use for your mother and they can tell you if you even have an option to NOT use a vault or grave liner . Hope this answers you question. --Jon Roeder