An irrigated electrophysiology balloon catheter with flexible-circuit electrodes is disclosed. To help prevent fluids, e.g., irrigation fluid or air, from passing between a space between an inner tubular shaft and an outer tubular shaft of the catheter, a first seal and a second seal may be provided about locations where the inner tubular shaft emerges from the outer tubular shaft. The materials and dimensions of these seals are instrumental in ensuring that the seals are sufficiently robust such that they do not fail during use of the catheter. Additionally, the flexible-circuit electrodes may include substrates adhered to the balloon. Delamination of these substrates may be prevented by use of a reinforcement component that extends the length of the balloon.