Barrel vaults are an arch that forms a tunnel. This tunnel will generally be dark as there are no windows on the vault structure.
Groin vaults are esetially two barrel vaults crossing eachother leaving an opening in the middle. You can cross as many barrel vaults over another as many times as you want, depending on the length of the vault you're crossing. This crossing of vaults allows more light to enter the vault, as there are more openings for it to get in.
The difference between a barrel vault and a groin vault is that a groin vault allows for more natural light to enter the structure. This light will create more variation in the interior spaces of the
Groin vaults are esetially two barrel vaults crossing eachother leaving an opening in the middle. You can cross as many barrel vaults over another as many times as you want, depending on the length of the vault you're crossing. This crossing of vaults allows more light to enter the vault, as there are more openings for it to get in.
The difference between a barrel vault and a groin vault is that a groin vault allows for more natural light to enter the structure. This light will create more variation in the interior spaces of the