Today's Daily Briefing comes from the desk of Steve Perron, News 4 Investigates producer.

Google "street creep" and you'll find several hits for an apparently popular skateboard, famous for its image of a ghoulish, distorted skull. Our story isn't about skate boards, but the image fits. For affected homeowners, "street creep" can really be a nightmare, and a very expensive one at that.

Our story reveals how "creep" is becoming more common in St. Charles County. County highway superintendent Rich Pieper says this is because developers are running out of flat land. So they're building on hills.

"Street creep" occurs when a concrete street expands and shifts, pushing into a homeowner's driveway. That pressure pushes the driveway into the home's foundation. That can cause the garage slab to seperate from the foundation and produce serious cracks in foundation walls.

Fixing the "creep" isn't cheap. While researching our story, we spoke with homeowners who faced repair bills ranging from $2,400 to $50,000.

It's a frustrating conundrum for consumers because while the problem is real -- and one the homeonwer has no control over -- the homeowner always gets stuck with the bill. A real estate attorney says this is because it usually takes several years for "street creep" effects to appear, and by then the builder is often out of business or the statute of limitations for breach-of-contract suits has expired. Insurace won't cover it because "creep" is not considered an "Act of God."

While this started out simply as a consumer-tips story, we quickly discovered it was something more, with the "more" being the reluctance, or inability, on the part of anyone in the concrete industry to say with any certainty what causes "creep." We can tell you there are several factors involved:

The type of soil on which the concrete is poured. St. Charles has a lot of "hydro-plastic" soil. This kind of soil is like clay... it shrinks a lot when it's dry and swells a lot when it's wet. This can lead to greater movement by concrete pads in streets and driveways. Also, we are told that hydro-plastic soils can be very slick when very wet, and that concrete can actually "slide" on it. Experts told us developers try to minimize this effect by laying down a thick layer of gravel or rock first, and then paving over that with concrete. Some county officials are currently trying to change code requirements so that developers will have to lay down deeper rock beds under streets, hoping that will help minimize "creep." But developers are reportedly opposed to this because of the added cost of the additional rock.

The terrain on which the homes are being built. Several experts we spoke with say that homes built on hills are more susceptible to "creep" because gravity will induce concrete streets and driveways to "slide" down hill.

The home's location on the street. There is general agreement that the certain spots on streets are much more likely to experience creep, than others. In our report, we showed damage to two homes that were both located at the end of "T" intersections. This is apparently a recipe for disaster, because the street directs pressure and stress from its own weight and the traffic directly into the driveway of the home at the end of the "T." If you buy or own a home at the end of a "T" intersection, our experts agree you should seriously consider installing modified (wider than normal) expansion joints at the point where your driveway meets the street. Other problem areas for "street creep" are on the outside edges of curves in the street and around cul-de-sacs.

So how do I prevent the "creep?" Everyone we spoke with for our story, from engineers to attorneys to members of the concrete industry (who spoke with us only on the phone... no one with the industry wanted to talk on camera for this story) agrees that properly installed expansion joints are the single most important preventative measure a homeowner can take to prevent the damaging effects of "street creep." Here is a good explanation of expansion joints. An expansion joint is a buffer (usually made of wood, rubber or other material) inserted between two slabs of concrete. Properly installed, it will shrink and expand as the concrete moves, ideally, absorbing the pressure and stress of the movement before it starts cracking and crumbling the walls in your home.

So, are you worried yet? Everyone we spoke with says you don't have to be, if you act soon. County superintendent Rich Pieper says you can conduct a rudimentary test of your own driveway for signs of street creep like this:

Check expansion joints. If the joints seem unusually tight or compressed -- you might say, "squeezed" or "crushed" -- you might have a problem. He also suggests taking a screwdriver or flat kitchen butter knife, and trying to tamp it down between the expansion joint and the concrete. Rich says you should be able to drive the screwdriver or knife blade down a good 4-5 inches. But, if you're hitting concrete at just 2 or 3 inches, your might have "creep."

Check garage floor/foundation. As our story showed, another good indicator is the condition of the concrete at the point where your garage floor and garage foundation are. If there are cracks in the foundation, outside or in, or if the garage floor slab is pulling away from your garage wall (foundation) then you may very well have a problem. Remember, these are all just possible indicators. If you have real concerns, you should consider paying a structural engineer to come out and take a look. It's expensive, but remember the cost to shore up a cracking foundation can run into the thousands of dollars.

Despite Rich Pieper's on-the-record statement that there are about "50 cases a year" in St. Charles County, Mark Luther, president of American Concrete Institute, Missouri Chapter, says the problem of "street creep" is "rare." Luther insists properly installed expansion joints will eliminate or at least reduce the damaging effects of "creep." Rare or not, at least one St. Charles county man thinks it is bad enough that he's working to manufacture and market a special expansion joint designed specifically to eliminate the "creep." Jason Lewis says he working with a manufacturer right now in Georgia, and hopes to have the product on the market soon.

The term, "street creep" seems to some extent to be local, like gooey butter cake and pork steaks. Even many local concrete professionals we spoke with while researching this story never heard the term, although once we described the phenomenon, they knew exactly what we were talking about. We have found the term "concrete creep" is more common in other parts of the country.

But we like "street creep," if for no other reason than the cool skate board with the scary looking skull.