The comment of Díez-García and co-workers on the article ‘Flat band potential determination: avoiding the pitfalls’ is a very valuable contribution to the discussion about the appropriateness of various models and techniques used for the determination of flat band potentials of semiconducting photoelectrodes, as well as other parameters. Such discussions will benefit the community and should improve the reliability of published parameters characterising photoelectrode interfaces with electrolytes. Herein we respond to the specific topics addressed in the comment: (i) the correction of the geometric photoelectrode surface area by surface roughness to enable more accurate characterisation of materials with nanotextured surfaces and (ii) the inclusion of photon flux limitation in the Gärtner–Butler model.