The Tenants Union Factsheet “Locks and Security” says this:
Under the terms of the standard residential tenancy agreement, you agree:
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not to alter, remove or add any lock or other security device without reasonable excuse (see below) or unless the landlord agrees
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to give the landlord a copy of the key (or other opening device or information) for any changed lock or security device within 7 days of the change.
I think it would be reasonable to send the tenant a letter telling them that by changing the lock without your permission, they have breached their tenancy agreement and have compromised your legal responsibility to maintain fire safety compliant doors.
In view of both of these breaches, and unless they are resolved immediately, they are liable for both eviction and the loss of their bond to pay for any damage done to the door in rectifying these breaches.
Will they please arrange a time for a compliant lock to be fitted by your tradespeople within seven days or you will commence proceedings to rectify the situation.
How about that?
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