Sealing Solutions to Safeguard Against Base Leakage
You will need to determine a sealing system based on what is compatible with the foundation that you choose.
Some examples of sealants are exterior caulking, silicone, or flashing, which will create a tight seal and prevent any water or moisture from penetrating the dome's base.
For example, if you have constructed the dome on a foundation that perfectly matches its exterior shape, you have the option to utilize flashing. Flashing is a material commonly made from metal or waterproof membrane that is used to extend the dome's coverage over the edges of the foundation.
If you're unsure as to what method is best for your project, we recommend that you consult with a local contractor or builder for advice.