[mulligan]

The water lines are actually buried 8 to 12 inches below the slab. Take a look when you drive by a lot with the forms for the slab in place, and pipes sticking up above. This is my main complaint with the builder (not bad, considering). If the hot water lines were buried a little deeper, and imbedded in ,perhaps, a spray-in styrofoam product, the results would be quite a bit better. If the builder had any real environmental responsibility, or was interested in 100% satisfaction of customers complaints on this issue, something would have been changed long ago. As it is, you as a homeowner, are paying for the several gallons of water wasted while waiting for hot, paying for that water to go through the wastewater system, and/or paying to have a recirculating pump installed. None of which is the correct fix IMHO. Even the pump, which is the most convenient fix, uses extra energy to reheat the recirculated water.