Cheque not cleared

If you have obtained valild receipt from builder for all your payments made to him, you need not worry about his non encashment of cheques.

You may issue registered notices as a precaution only asking him to encash the cheques as undrawn balance may be misunderstood at a later date and may miss your attention in not keeping sufficient balance in future.

It is the responsibility of builder to encash the cheques, and your right is getting valid receipts and peaceful possession as per contractual obligations.