Water damage is one of a homeowner's worst nightmares. Even the smallest plumbing or roof leak may wreak incredible havoc over time. Not only is it capable of damaging your furniture and other possessions, but this problem also threatens human health and the structural integrity of your home. So you can see it's important to stay alert for the first signs of unwanted water. The trouble is, though, that these signals are often so subtle you might make the mistake of not paying much attention ... until you are facing serious consequences. Here are the signs of water damage to watch for so you can take care of a roof or plumbing repair before it's too late.

Paint that is blistering, bubbling, and/or flaking is one of the best clues ever that you've got water somewhere you don't want it. (Ditto for loose and peeling wallpaper.) If you are in the process of shopping for a new home, beware of any house where only certain areas, such as ceilings or single walls, have been freshly painted. Rather than merely redecorating, the seller could well be trying to cover up signs of water damage.

The kitchen or bathroom sink might call out to you for help, via a faucet base that is coming loose or caulk that's deteriorating. Especially when those are combined with a laminate countertop which is detaching from the base or mysterious dampness found in the undersink cabinet or vanity, you have got yourself the recipe for one giant leaky disaster.

Floors made of hardwood, engineered wood, or laminate are beautiful and trendy. But when you see wood floor planks that are buckling and sticking up above their neighbors or have shifted out of place, you've got a problem. Tile floors may tell a similar sad story. If they are loose or remain inexplicably damp for hours after anyone's used the tub, watch out.

Doors and windows which gradually become harder and harder to open and close are probably trying to whisper to you a nasty little secret you can't afford to ignore ... namely, that their wooden frames are swollen due to water absorption.

Walls and ceilings might also spill the beans about water troubles. Look out for drywall with stains (which are usually yellow or brown) or swollen edges and seams. Wooden wall trim -- such as baseboards, crown moldings, or the like -- that has started to crumble is problematic as well.

Foundation cracks could be the result of frost heave from those inevitable freeze-thaw cycles experienced in northern climates. However, you should never overlook the possibility that the cracks you see are signs of water damage instead.

Your nose will often give you the bad news. A musty mildew scent is not inevitable in every older home; check out where it is coming from. And that's not the only odor to watch out for. Water damage may sometimes result in an acrid smell reminiscent of wet diapers. (Phew!) Even before any odor at all appears, your nose may sniff out the presence of water damage and react by itching, dripping, and sneezing.

Your ears might let you know that water is mysteriously running or dripping even at times when no one's using the plumbing. Don't simply chalk these sounds up to your overactive imagination. Rather, look for a leak.

Your wallet may start hurting. Should you find that you're suddenly shelling out much more cash for your monthly water bill than usual, investigate. Wasted water due to a plumbing leak is most probably the culprit, with water damage as its partner in crime.

If you come across any of these signs of water damage, don't bury your head in the sand. Call a plumber (or a roofer, if the water's coming from overhead) before the problem gets worse.

Laura Firszt writes for networx.com.

Updated August 30, 2018.