Can a shed be built within a distance of 1.5 meters from a rural self-built house?

You can't. According to the information of the Land Management Law, if rural villagers illegally occupy land to build houses without approval or by deception, the land administrative department of the people's government at or above the county level shall order them to return the illegally occupied land, dismantle the newly built houses that exceed the standards set by provinces, autonomous regions and municipalities directly under the Central Government within a time limit, and the occupied land shall be punished as illegal occupation of land. Therefore, scaffolding shall not be built without authorization within 1.5 meters of rural self-built houses.