Minn. Stat. § 510.05: LIMITATIONS.

The amount of the homestead exemption shall not be reduced by and shall not extend to any mortgage lawfully obtained thereon, to any valid lien for taxes or assessments, to a claim filed pursuant to section 246.53 or 256B.15, to any charge arising under the laws relating to laborers or material suppliers' liens or to any charge obtained under section 481.13 pursuant to a valid waiver of the homestead exemption.