When a non-conforming building, or a building in which a non-conforming use is conducted, is destroyed or damaged by any casualty to an extent not exceeding 50% of its true value, exclusive of foundations, at the time of such destruction or damage, it may be reconstructed but it shall not be enlarged. If any such building is so destroyed or damaged to an extent exceeding 50% of its true value, it shall not be reconstructed except for a conforming use; provided, that if any non-conforming building used as a one-family dwelling or two family dwelling is so destroyed or damaged to an extent exceeding 50% of its true value, the same may be reconstructed within two years after such destruction or damage so as to be the same space that is occupied prior to such destruction or damage or any part thereof.

No non-conforming use shall be extended at the expense of a conforming use.

Nothing in this chapter shall be deemed to prevent keeping in good repair a building in which a non-confirming use is conducted.

A non-conforming use may be changed to another non-conforming use of the same or more restricted nature (less intensive use).

If any non-conforming use ceases for a continuous period of one year or more, is changed to or replaced by a conforming use, or is moved for any distance for any reason the land and building theretofore devoted to such non-conforming use shall thereupon be subject to all the regulations as to use for the district in which such land and building are located, as if such non-conforming use had never existed.

The foregoing provisions shall apply to all non-conforming uses existing at the time of the adoption of this chapter and to all uses that become non-conforming by reason of any amendment thereof.