Tenant breached rental agreement and not vacating despite serving lawyer notice

Hi, In March we entered into a rental agreement with 2 co-tenants. This was meant for residential purpose as outlined in the agreement however the tenants have constructed a huge shed covering the full premises which makes it look like a warehouse/factory rather than a residential house. During the initial discussions they sought our verbal permission to construct a shed inside the premised but did not disclose the size and we never expected it would so huge that it would cover the entire house and make it look like a warehouse. The society members have come up and started complaining that we cannot tolerate a commercial built up in a residential colony. We are with the society as we were also shocked looking at such a huge shed covering the full house. We served a notice to evict owing to the breach of contract as it was only given for residential purpose. Now the tenant is not agreeing to evict. Note that the agreement is for 60 months with possibility of vacating after 36 months by giving notice of 3 months but due to the breach of agreement we have notified them to vacate after 3 months however they are not willing to vacate. kindly advise what is the option left for us as landlord. We are afraid that it will lead to encroachment by the tenants. the court case will take longer to sort this out but what are all the legal options and rights that we have - please kindly advise. Thanks a lot.