Generally no, not without the agreement of the party who benefits from the easement, since building over it could obstruct their legal right, such as access, drainage, or support. Some easements, such as underground service easements, may allow limited surface works if the right itself is not interfered with, but this needs to be confirmed with the beneficiary and, often, a utility provider.
Whether you can build over an easement depends on the type of easement and whether the proposed structure would interfere with its exercise. Building directly over a right of way that obstructs passage, or over a drain in a way that prevents access for maintenance or blocks flow, would generally not be permitted without the agreement of the party benefiting from the easement.
For underground service easements, such as a water main, sewer, or ESB Networks or Uisce Éireann infrastructure, there are often specific setback or exclusion zone requirements published by the relevant provider, and building within these zones without consent can be prohibited even if the surface use seems minor, because of the need for future access and the risk of damage to buried infrastructure.
In some limited cases, light structures that do not prevent the easement being exercised, such as a driveway surface over a buried pipe that remains accessible, may be acceptable, but this always needs specific confirmation from the beneficiary or utility provider rather than being assumed. Building over an easement without agreement risks enforcement action, a requirement to remove the structure, or liability for any damage caused to the underlying service.