i have moved the stairs in the house but now the light switch needs moving i have bought new cable but what is the best way to joint it .
as it will be going under plaster someone told me to use block connectors with plenty of insulation tape
fraid not, bad advice!
If possible find switch wiring under floor, (presuming top switch?) fit proper junction box and route to new position going vertically up (or down) wall, there may be one 3 core & earth & possibly 1 twin& earth.
Note connections before disconnecting sw. as prob. 2way, if 3c. only then connect new cable wire for wire, if also twin then you join at j.b. as it was at switch, ie common of switch only has one core & others have 2 in each...clear as mud...