Do you need a special site type if considering building a Passive House Building?

No, generally not. Of course, it is ideal to be able to design the building to face north, and to avoid over-shadowing by coniferous trees or local buildings. However, if these conditions do not exist on your site, then don’t worry. Allowances can be made, and tested in the PHPP software, for any shortfall in terms of ideal orientation leading to reduced solar gain.