The base contract with our custom home builder does not include a structural warranty. They said if we want one they will get one for us as a change order. Our lot has expansive soils and we will be paying for 5 feet of soil to be removed and new fill will be brought in. There is also a footing that will be built as the lot has a gentle slope in the build area. Since most foundation issues seem to be from soil movement it seems like we would be good candidates for an insurance policy even though our builder has a reputation for quality work. What should we look for in the warranty? Are there any companies recommended?