D.C. Code § 40-301.01
Every building erected, improved, added to, or repaired at the direction of the owner, or the owner's authorized agent, and the land on which the same is erected, intended to be used in connection therewith, or necessary to the use and enjoyment thereof, to the extent of the right, title, and interest, at that time existing, of the owner, shall be subject to a lien in favor of the contractor who contracted with the owner, in the amount of the contract price or, in the absence of an express contract, the reasonable value of the project; provided, that to enforce the lien, the contractor claiming the lien shall record in the land records a notice of intent and comply with the other procedures prescribed in this chapter.
D.C. Code § 40-301.01
Condominiums, see § 40-1902.02. Horizontal property regimes, see § 42-2025. Payment as defense to assertion of lien, see § 47-2883.03. .