Is condensation in my loft the same as a roof leak?
No. A roof leak is caused by external water entering through a defect, while condensation forms when warm moisture inside the property meets cold surfaces in the roof space. They can look similar, so checking ventilation, insulation and the external roof covering is often necessary before deciding on repairs.
Telling them apart
Timing is the most useful clue. Damp that appears during or shortly after rain and dries out afterwards behaves like a leak. Damp that appears in cold weather, is worse in the mornings, and shows across a wide area behaves like condensation.
Water droplets on the underside of the roofing felt across much of the roof space point strongly towards condensation rather than a defect in the covering.
Why the distinction matters
Condensation is a moisture and ventilation problem. Repairing tiles will not solve it, and sealing gaps can make it worse by reducing airflow through the roof space.
Left alone, persistent condensation affects timbers and insulation in much the same way as a slow leak, so it is worth diagnosing properly rather than assuming either cause.