The builder versus the engineers

For the past couple of weeks we have been between the builder and the engineers. There are two 5"/14" beams that will hold up the entire house now that we have taken down the stone pillar that was resting on one rock. Will they hold or won't they? The engineers say yes, they will hold, no problem. The builder, the person right there watching this beam bow with just a little weight on it, says no way is he taking out the support. The engineers insist the beam is large enough to hold but the engineers are in Philadelphia. The builder is standing under the beam. Who would you go with? We went with the person under the beam. We now have two 7"x14" power beams in the basement and so far, so good. Still waiting for the other chimney to be built. Still waiting for the chimney professionals to come up with one answer for lining the chimneys. We have been told a 5" flu is sufficient, a 9" flu is good, a 10" is okay and 'I wouldn't go with anything under 12". Two flu liners, a 9" and a 5" would be just as good as a 12" (wrong). The liners need to be insulated to 'Why insulate? It's a masonry chimney'. The chimney needs to be pargeted to 'Why parget it? You're going to need a liner anyway'. We now know the elusive mathmatical formula to calculate the size of the flu (height x width divided by 12 - not exactly rocket science) and are looking for someone to install it. Summer is winding down and we haven't even started on the footings yet.