The occurrence of sheetrock or plaster cracks occurring at the ceiling or wall surfaces within your home is a common issue that many homeowners will encounter. This is normally not a structural issue and can be rectified very easily.
Why does this occur?
In most residential and commercial properties, the walls and ceilings consist of a sheetrock that is glued and screwed to either metal or wood studs. This sheetrock is a rigid product that does not flex easily and has a tendency to tear or rip if stressed. In addition the joints between the sheets of sheetrock are taped with a compound that when dry, becomes exceptionally rigid and brittle. In most instances the joint itself is also covered with a tape of either reinforced paper or a synthetic material, such as fiberglass. This tape will offer some additional resistance to any breaking of the seams; however, this reinforcement is not substantial and will not stay intact with any real type of movement.
The reason why the interface between the walls and the ceilings will often crack is the flexing of the ceiling rafters from a load on the upper floors. For example if the ceiling of the second floor is cracking at the walls, and the next floor up is the attic, there may have been some loading of the attic floor. This loading will cause the flexing of the ceiling joists of the floor below the attic, or the attic floor joist, due to any load placed on the attic floor. If these joists are loaded and they flex, the movement will cause the actual interface of the ceiling and the wall to move. This movement will cause the sheetrock joints to experience a stress that breaks the bond of the taping compound, developing cracks and inconsistencies in the surface of the wall or ceiling. Again, this is normally not a serious issue, merely cosmetic.
In most cases, these cracks are simply minor cracks that are not of any structural concern. They are purely aesthetic and may even close up, if the loading of the upper floor is not reoccurring. This is one of the extremely common occurrences, especially in a new home, or a home that is being used in a different fashion than in the past. If you are a new owner and decide that the attic space is good for storage or even occupancy, and the past owners did not use this space, cracking may occur due to the new stresses placed on the floor of the attic and in-turn the ceiling of the floor below.
Another very common reason for cracking or imperfections occurring on the ceilings or walls of your home, especially if the home is new, is the shrinking of the wood that has been used to construct your home. When lumber is purchased, the overall moisture within the wood is controlled by the lumber yard. Commercially built projects are strictly monitored for the amount of moisture allowed within the framing lumber of the structure. Obviously building components that are made of wood originate from living trees. These trees survive by the presence of water within the wood fibers allowing the tree to live and grow. This water is inherently present after the tree is cut down and manufactured into wood shapes for construction. The drying of this lumber is important to the proper development of the wood as usable construction components. However, all structural wood will have a percentage of water within the wood fibers. As time goes on and the wood dries out, this water will evaporate and dry out of the wood fibers, causing the structural member to shrink. This shrinkage will cause the stresses within the joint compound of sheetrock and create what are referred to as shrinkage cracks. These shrinkage cracks are the cracks that many homeowners will be concerned about, after they have lived in their homes for a length of time. Again, like the cracks caused by the loading of upper floor joists, in most cases these cracks are neither serious nor structural. They are merely cosmetic.
Another reason for surface cracks on sheetrock surfaces is an insufficient number of fasteners that have been used to install the sheetrock onto the metal or wood studs. The proper and best method of fastening this product to the studs is to glue and screw. This refers to the method of running a bead of construction glue down the surface of each stud and applying the sheetrock panel to the studs with screws that are spaced a maximum of 6 inches apart. This technique of course, takes time, and is not the most efficient method for sheetrock installation. In addition, this technique causes a significant number of screw heads to be patched and blended into the surface of the sheetrock. As can be imagined, the more efficient contractors will try to limit the amount of screws used per panel of sheetrock, to minimize the time required to install the panel, as well as the number of screw heads that will need to be patched. However this economy will result in more cracking of the taped joints in the future, if the screws and or the glue is minimized.
Another reason for blemishes, cracking or tearing of the sheetrock or drywall will be the popping of the screws used to fasten the sheets onto the studs. Years ago, sheetrock nails were used to fasten the sheetrock to the studs. These nails had more of a tendency to pop out of the stud than the screws that are more commonly used today. However, the use of nails does still occur and some installers prefer to set the sheetrock panel with a few nails and then finish off the fastening with screws. The reason for this method is that it is easier for one man to install the sheetrock panel with a hammer and a few nails, than to hold a heavy screw gun to initially fasten the panel. Obviously once the panel is fastened, the use of a screw gun is very easy and systematic.
In almost 99% of the cases, there should be no concern regarding structural issues or problems due to minor cracking or imperfections in your sheetrock surfaces. This is extremely common and should not cause alarm.
How can these sheetrock issues be corrected?
As with any sheetrock or drywall issue, the correction of the problem is normally extremely easy and can be performed by the most novice of homeowners. Sheetrock is a very forgiving product, and the repair is as simple as taking a taping knife ( found in any hardware store ) and applying a thin layer of taping compound over the blemish. If the problem is a deeper cut or puncture, the correction is identified in a more detailed presentation entitled Sheetrock, Drywall repair located within this website.
I often advise individuals that have just purchased a new home to wait a period of up to two years, prior to repainting the interior of the home. In many instances, if the home is being constructed for your use, then only have the builder paint the homes interior with a primer coat of paint. This is difficult for individuals, due to the excitement of moving into a new home, but the final paint should be applied after all of the shrinking and movement of the structure has occurred. If this period of time is allowed to pass, then the majority of the cracks and blemishes within the drywall surfaces will have occurred and the newly applied finish coat of paint will fill them in.
In almost all cases, the presence of drywall cracks and blemishes does not indicate any significant problem or issue. The correction is simple and can be performed by the everyday homeowner.