I have, on more than one occasion found a sac spider gazing up at me from a bunch of grapes in the local large supermarket. They construct a silk-like retreat in a curled leaf or in the heads of Protea flowers. With the onset of summer they find houses an ideal habitat, constructing their sac retreats in the folds of curtains, bedding, clothing, doorframes and corners. Being active at night, it is then that most bites occur when the animal is inadvertently pressed against the body, as the large fangs of this spider are capable of penetrating light fabrics. Other Miturgidae spiders are also nocturnal, free ranging, cryptic and terrestrial and resemble the Lycosidae and Ctenidae.
Some species live in caves and rock recesses.