Dirty or stained: Splotches or stains on surface are usually caused by the application of a liquid that soaked into the porous surface of the concrete. Sealing the surface against spills can prevent this.

Cracked or chipped: Often fissure openings in the surface or small pieces breaking away are signs of future problems. Take these tiny signals seriously.

Edge is cracked or broken: Unfortunately, any hard surface can chip or break away at the edges. Commonly caused by impact or erosion, cracks can be fixed if the problem is small.

Flaking: If you see the surface breaking away, this may signal that the concrete mixture may be flawed. Concrete's unique blend of elements gives it strength and durability. Flaking is not a common characteristic. Flaking can also be a sign that the concrete was poured during cold weather. A strong freeze will cause the new surface to become brittle and can make the surface prone to flaking. Some surfaces can be repaired; if damage is deeper, the pad will need replacing.

Settling: A common cause of damage as soils shift up and down over time. Concrete is designed for strength but not necessarily extreme flexibility. Small shifts are OK, but larger shifts will damage concrete. Settling is often a serious and expensive problem. In most cases, repair is not an option.

Different concrete floors will require different repairs.

Here are some common choices:

Sub floor (living space): Most sub floors for living areas are made of framed wood. The sub floor is the structural floor underneath the hardwood or carpeted floors you walk on. Concrete sub floors are usually found in basements or in remodeled garages or patios.

Finish floor (living space): Most living areas are finished with tile, hardwood or carpet. Concrete is not a common floor finishing for living spaces. Possible exceptions are utility rooms or laundry rooms.

Garage or basement: Concrete is the universal surface for garages and basements. These areas often get heavy traffic and require easy maintenance. Damage often is caused by dropped objects or shifts in soil.

Driveway/parking area: Concrete is the most common surface for driveways and parking areas. These areas get heavy traffic from heavy objects. Damage can be caused by shifts in soil or the freeze/thaw cycle. Extremely heavy trucks can also damage the surface. If you anticipate heavy traffic, you should consider adding steel reinforcement and pouring a thicker pad.

Exterior walkway: Concrete or stone masonry are popular options for exterior walkways. Stone masonry will be more decorative; however concrete will be less expensive and lower maintenance. A common cause of failure is sitting water that can cause a freeze-thaw cycle.

Patio: Like walkways, concrete or stone masonry are popular options. Settling soil is a common cause of damage. Concrete pads reinforced with steel beams can prevent this. If the damage is severe, you may want to consider replacing the patio with a new pad. Attach the steel reinforcement beams into the house foundation for further strength.

Pad for light structure: Detached garages, sheds and porches often have a concrete base flooring for support and structure. Settling soil is a common cause of damage.

Steps: A basic problem with concrete steps is settling; sometimes the steps will settle at a different rate than the porch or walkway. You can prevent this by replacing the steps with new concrete. Attach the steps to the patio or walkway with steel reinforcement. Concrete floors with special applications sometimes need special repairs. Does your floor fit the following?

Special color or other additive: Concrete can come in a wide variety of colors created by adding dyes to the liquid mixture. Fixing damage to colored concrete is tricky. Getting the right blend of colors is not an exact science. Don't expect a repair person to create the perfect match. If a perfect match is critical, consider removing and replacing the area with new concrete.

Lightweight concrete: Concrete comes in different forms with different mixtures of cement, gravel and water. Some applications call for very lightweight concrete. Repairs need to have the identical lightweight mixture.

-- Tips courtesy of HomeAdvisor.com