Should you seal or waterproof gravestones?
No, No, No!
Don’t seal or waterproof your gravestones. A stone has to be allowed to have air and water pass through it. Any repair or cleaning technique that would prevent this process will have later damaging effects on your stone. The stone is in direct contact with the soil and will wick up whatever is around it. That includes cleaning chemicals, herbicides and water. Sealing, waterproofing or coating the stone face with any sealing process would inhibit its ability to naturally evaporate this moisture from inside the stone. This will cause new damage and expansion problems.
Thoroughly investigate the issue before making a decision on such a process. A consolidation process (which is costly and must be done by certified technicians) has been used on sandstones in some areas and so far has been successful. Speak to a certified conservator to learn more about this process. Gravestones can’t be treated the same as buildings. Cleaners and products that are recommended for buildings of the same material are not to be assumed appropriate for gravestones. Unlike a building, they are buried and in direct contact with the soil and are exposed on all sides to the environment. Newer stones or granite and stones with large foundation bases may be treated differently than an old 1700’s sandstone tablet. Conservators are learning new methods and other techniques are being tried every day; we only ask that you take the time to learn about your options before making a decision that can never be undone.
For more information, contact CGN.