I would think that septic systems would be hard to warranty due to the builder having no control over how its used. Have you checked with your county to learn what was required of the builder at the time the permit for the septic system was issued? example was there a perk test and is there a record of the results? Does your county require builders to us only state licensed septic system installers? Did the county keep a record of the septic systems design so you can learn if the design met the lowest min standard for zoning OR if it exceeded min standards? I would bet that the more homework on this you do your self then should you have to hire a atty to assist you the easier and lower the cost would be for them to assist you . After such a short time being in the home by chance were you ever given any information on how to properly use and care for the system? unfortunately there are alot of people who tend to forget and end up treating septic systems just as if they were city sewer dumping every and anything down the drains. Causing systems to gum up, leach lines to plug, accidently destroy septic systems bacterial growth. ETC the list goes on. many people trust product info and flush things that claim they are septic safe when perhaps the product should never have been flushed in the first place. LAST if your home had a written warranty explaining what was covered how does it address the septic system ? The more homework you can do the better on this. In fact before you try the links up top locating a atty to assist you why not see if you can get a copy of the septic systems design and take it to a licensed septic system designer and have it reviewed even if you have to pay a small fee to have them give you a opinion of it.