Date Published: October 2012
Generally, the level of environmental review required depends upon the program design and project description. All the activities described in this question-- demolition and rebuilding of a single-family home on a single site; acquisition and disposition of an existing building; rehabilitation of a home-- would all be considered categorically excluded from the National Environmental Policy Act (NEPA), subject to Part 58.5 (Related Federal laws and authorities). Where they do differ is in how compliance with the Federal laws and authorities applies.
It should be noted that each of these categories of categorical exclusion have criteria that, if exceeded, require preparation of an Environmental Assessment instead. See 24 CFR 58.35(a) to review these criteria.
Please refer to the HUD Environmental Review Requirements.