  We study stochastic homogenisation of free-discontinuity surface functionals
defined on piecewise rigid functions which arise in the study of fracture in
brittle materials. In particular, under standard assumptions on the density, we
show that there exists a $\Gamma$-limit almost surely and that it can be
represented by a surface integral. In addition, the effective density can be
characterised via a suitable cell formula and is deterministic under an
ergodicity assumption. We also show via $\Gamma$-convergence that the
homogenised functional defined on piecewise rigid functions can be recovered
from a Griffith-type model by passing to the limit of vanishing elastic
deformations.
