If you can confirm you have termites then yes you should go to the landlord and ask him to remedy the problem. I would advise you to call a professional and have them come in and prepare a report for you. Once prepared present it to your landlord if you feel this is something that you do not want to live with. Be prepared though to have to accept the consequences, like if the home needs to be tented etc… The obligations of the landlord should be spelled out in the lease. IMO termites are not the same as say roaches or mice however if it bothers you alot you should first review your lease, then approach your landlord. Also if it is a degree of infestation that you cannot tolerate then even if it is not spelled out in the lease, you should be able to get it remedied.
