Part 3
Matters of justification or excuse
Defence of property
55 Defence of dwelling house
Every one in peaceable possession of a dwelling house, and every one lawfully assisting him or acting by his authority, is justified in using such force as is necessary to prevent the forcible breaking and entering of the dwelling house by any person if he believes, on reasonable and probable grounds, that there is no lawful justification for the breaking and entering.
56 Defence of land or building
(1) Every one in peaceable possession of any land or building, and every one lawfully assisting him or acting by his authority, is justified in using reasonable force to prevent any person from trespassing on the land or building or to remove him therefrom, if he does not strike or do bodily harm to that person.
Self-defence - national proceedings
EDIT.