i sent this to someone else when they asked for some help...so sorry if it is out of context but im not typing it all again...these are a few tips on how to tell if your house has foundation problems (engineering firm is my job)
first, get elevations of the house. it will show the floorplan with numbers in each room. they should mostly be between -.5 and .5 (inches). this is how high that part of the foundation is in that particular part of the room with respect to the center. by the way, getting it examined by an engineer means nothing. the quality of the engineer can change so much you wouldnt believe it.
anyways, walk around and look where the downspouts go away from the house. if the grade of the pipe leading away isnt to code, it will cause a heave in the foundation (uplift) and none of the doors perpendicular to the outside wall will close right. look for cracks in ceiling drywall. it usually follows the lines of where the drywall meets another piece. that is caused from settling (not enough water below the house, usually caused by trees). if trees are fairly close or any limbs overhang the foundation, ask if there is a root barrier. if there is no root barrier, you need to MAKE SURE the roots are either not under the house or are not already causing problems. a root barrier can be installed but they are expensive. plus, if trees are already hurting the moisture in the area, a root barrier will only stop it from breaking more, not fix it. if it has sprinklers, make sure they dont shoot away from the house completely. the soil needs to be saturated somewhat. if there are trees around the house, it needs more water than normal. trees suck water out of the ground like no ones business.
check all of the closets, nooks, little spots, tile, brick, stone, exposed foundation and anything else that is a stiff substance for stairstep cracks, hairline cracks, breaks in joints, etc. if you look at the ground right next to the house (on all sides) it should either drain away, have drains, or be graded so water gently rolls off dirt the other direction.
by the way, find out whether or not the house has piers under it. if it has piers, you dont need to worry about anything i said about the trees. if it has piers, that means it is standing on them. imagine standing on stilts. that is exactly what your house is doing. the piers are sitting on bedrock 15-20 feet below the surface. there is no way they are going to sink. only think you have to worry about is uplift (heave). to stop that from happening, make sure gutters, sprinklers, culverts, downspouts, etc are leading away at sufficient grade. also visually inspect the perimeter of the house and make sure 2-3 inches of the slab are above ground. that prevents water from entering the house.
if your house isnt a slab, let me know, ill let you know what to look for on a pier and beam or cmu block foundation (it has a crawl space under it, you can see under the house). those types of foundations are far superior to slabs.
if you have a pool, walk around and look at the edges. about 10-15 inches away from the waterline, if there is a crack that circumscribes the pook, that is ok and normal. a long time ago they used to build it such that the crack you see would happen. the pool does not move up and down, the surrounding ground does. they didnt know that in the late 70's and 80's, and once these cracks started showing up, the started to build them differently. if you see a joint around the pool (thin strip of wood or plastic) that is a newly designed and should-not-crack pool.
everything i have said is assuming the foundation/pool is designed properly.
do you have attic access? if so, look in the attic around the sides and see if there is a piece of wood bracing every OTHER rafter. the rafters running straight up the roof should be 16-24 inches on center (Depending on design) and there should be a perlin brace every OTHER one of those rafters. ive been in houses that were missing 2, 3, and even 4 perlin braces in a ROW. if you walk outside after observing that, you can see the settling pitch in the roof.
let me know if anything didnt make sense.