I have a long run (1300') of PVC for some decorative lighting along a driveway. The lamps will be spaced about 130' apart. I'm wondering what the experience is regarding expansion/contraction of the PVC conduit. I know the temp down at 4' or so is pretty constant, but at 2' I'm not so sure it's constant. I certainly don't want any fittings to pull apart. Above ground, expansion fittings would be mandatory.