If one makes improvements to the property of another without his knowledge, the owner must pay him for the improvement. This is not 16 in the Schottenstein BK, 101 a2.
If my house needs a paint job and you come paint it without my consent, why do I have to compensate you? I neither asked for it nor wanted it done!
Barry Epstein, Dallas, USA
The Gemara in Bava Metzia 101a states that when one who plants another's field without permission, Rav says that we assess the improvement and the cost and the owner pays the lower amount. Shmuel says that the owner must pay as much as he would have paid to hire someone to do the job. The Gemara continues that they are not arguing Rav is speaking where the field was not earmarked for planting and Shmuel is speaking where it was.
The Rambam writes that the owner can tell the planter to take his trees and go away, and the landowner's liability is only incurred if he wishes to keep the improvements. There is a difference of opinion whether the Rambam is referring even to the case of Shmuel or only where the field was not earmarked for planting.
As for painting, the Rema (Choshen Mishpat 375:7) writes that the owner can say that he was willing to live without it (and is thus exempt). In any event, even if we will assess the improvement, its increase to the value to the house is likely to be negligible.
D. Zupnik