It is entirely possible your tile lifting has nothing to do with the tree. All concrete slabs will crack. The trick is to make them crack where you want them to crack. Tile set over a concrete slab will crack along with the slab or lift, but only if set improperly (such as without an isolation membrane). First, get a reputable tile expert to look at your tile problem. The TCA (Tile Council of America) may be able to assist you in finding someone local, or you can ask around at local tile places - just make sure they are competent (don't bother with places like Home Depot).

But... if the tree is the problem, at the mature size it apparently is now, it may be possible to cut a couple of damaging roots without having to kill the tree (that has lots more) as long as it wouldn't jeopardize its stability.

ok..so far the answers are surprisingly hopeful. i guess the first thing to do is contact the tca. actually, i thought i'd have to get an engineer or something. i didnt know that you could get rid of (some) roots without killing the tree.

i really have to keep my fingers crossed on this one.

Let us know what you find - posting some pics might help. It's always difficult to attempt to diagnose a problem without a visual.

Novacat, just a cautionary note on those "flying ants"...make sure they are not termites. They look very much alike.

i'll try to post some pics. i already emailed tca and waiting for a response. lotodig, yes they are flying ants. last friday (after my 1st email to you guys)when i came home fom work, i walked into the kitchen and there was yet another swarm of flying ants together with tiny little crawling ants on the opposite side of where the door and the cracked tile are. they were coming out from under the molding of an interior wall. now i have another question...about 2 weeks ago i sprayed my backyard with a bug spray, the one that gets attached to a hose. i was getting lots of regular ants on the deck (that is right outside of my kitchen door) so i sprayed the deck and was real pleased that even to this day there are no ants on the deck. is it possible that by spraying the deck i "drove" the ants inside (assuming they were living under the deck)? please note that the deck is low to the ground, only one step up from the grass.

Sure it's possible, especially if the tiles made it easier.

I would see if you can get someone in there with a small backhoe and dig down along the foundation. There are all kinds of people with backhoes that fit on basically the back of a garden tractor.. More than likely your initial suspicion is correct. The roots to the Swamp Maple is under the slab causing problems. A tile company will not remedy the situation as they will either say that cracked tiles are form a cracked slab ot inferior installation. I would rather spend a little bit of money and either confirm what you first thought, or at least have some piece of mind that the roots are not under the slab. Swamp Maples or Silver Maples as they are commonly called, cause thousands of dollars damage every year t sewers, septic systems, sidewalks and foundations. The roots can be massive and run for many feet in all directions.

On the other hand with the flying ants.....you may also have carpenter ants. If the tree is that close to the house, chances are that it is shaded, dark, and damp, around that tree and that is an invite. Check this for a comparison of flying ants vs. flying termites

http://www.pestproducts.com/flyingants.htm

Here is another site for the Carpenter ants / Termites / Flying ants

http://www.the-piedpiper.co.uk/th3f.htm

Here is a link that might be useful: Flying ants

kevin, thanks for your response. i had a friend come in and he said exactly what you said. he told me to dig around the foundation and see if the roots are going under the house. problem is, the deck is right against it. so i have to remove (some of )the deck in order to dig around. so far, the flying ants problem is gone. they're not coming in from the cracks anymore. but i'd be fooling myself by thinking i dont have to fix the problem. i guess when the weather is cooler, i'll have to take care of the problem. and yes, they were flying ants (probably carpenter ants) not termites...they have the pinched waist. i dont know if they're gone because of the season or because i sprayed the heck out of it for weeks. this is gonna cost thousands!