Is it legal or standard practice to have a one sided (on the side of the landlord) indemnity clause on a commercial lease contract? Also, is it legal for them to ask you to waive your statutory rights?
In short, yes, indemnity clauses can be one-sided. That does not mean that the landlord cannot be held liable for damages you suffer due to a breach of the contract by the landlord. Indemnity clauses should always be reviewed before you sign a contract as they can subject you to a lot of risk.
As for the waiver of statutory rights, it depends on the right at issue. There are some rights/protections you can waive and others that you cannot.
It is common for commercial leases to be one sided and very favorable to the landlord. Usually, unless the tenant has a significant presence, such as an anchor tenant in a shopping mall, the commercial tenant does not have a great deal of room to negotiate. Sometimes, however, landlords exceed what is allowed by the law. It is a good idea to hire a lawyer to conduct a review of a commercial lease to give you advice concerning the consequences of the provisions contained in the lease, even if there is not much room to negotiate.