The Housing Capacity Preservation Amendment Act of 2025 aims to amend the Historic Landmark and Historic District Protection Act of 1978 by ensuring that the review of new construction by the Historic Preservation Review Board does not lead to a reduction in housing units or density below what is allowed under existing zoning regulations. Specifically, the bill introduces a new subsection that states any finding of incompatibility should not result in a decrease in the floor area ratio, residential square footage, or dwelling unit density below the permitted levels in the relevant zone district.

Additionally, the bill includes a deletion of the term "height" from a specific section of the law, which may relate to the criteria for assessing new construction. This legislative change is intended to protect housing capacity while still allowing for the preservation of historic landmarks and districts, thereby balancing development needs with historical considerations. The act will take effect following the Mayor's approval and a congressional review period.