Residential Tenancies Act 1986, ss 40, 41, 45, 49A
You, the tenant, are not responsible for damage that happens through normal use over time – called “fair wear and tear”. For example, if the carpet in the hallway starts to develop holes just through normal use, you don’t have to replace it. It’s the landlord’s responsibility to keep the place in a reasonable state of repair.
You’re also not responsible for damage that’s outside your control – storm damage, for example.
The landlord also has to comply with all building regulations and health and safety requirements.
Case: Tenancy Tribunal 4081393
The landlord’s responsibility for maintaining the building includes keeping the outside of the building clean, if it’s dirty because of normal factors like dust and dirt carried by the wind. You the tenant will only be responsible for cleaning the outside if you’ve somehow contributed to it being dirty.