Can wall cavity insulation stop rats?

Wall cavity insulation can help deter rats to some extent by making it more difficult for them to nest and access wall spaces. However, it is not a foolproof solution, as rats can still enter buildings through gaps and holes. Effective pest control requires sealing entry points and maintaining good sanitation practices, in addition to using insulation. Thus, while insulation may reduce their presence, it should not be relied upon as the sole method for preventing rat infestations.