Using all purpose or lightweight drywall mud with mesh tape can often lead to cracking. Cracks sometimes develop where drywall corner bead is installed. This is often due to improper installation. There are different types of corner bead and each type has specific requirements for installation. For example, vinyl corner bead can be installed with spray adhesive but if the wrong type or not enough adhesive is used, cracking may occur when the building settles.
If staples are used to install vinyl corner bead and it is not done properly, it can cause cracking later on. When installing metal corner bead, screws or nails are required to give the corner sufficient strength. However, if not enough fasteners are used or they are spaced too far apart, it can lead to cracking during settling. Drywall contractors have differing opinions as to what is the strongest method for installing corner bead. Many feel that the paper-faced "tape-on" corner bead is the strongest and least prone to cracking.
We have found that in situations where you must ensure a very strong corner that prevents cracking in the future, paper-faced corner bead installed with all-purpose drywall compound is the best option. See also how to coat corner bead? Another common problem with drywall is nail pops.
Nail pops occur when the head of a nail "pops" through the paper of the drywall and creates a separation in the paint. They look like small round circles the size of the nail head. Nail popping is another common reason for drywall cracking. This is when the nails holding the piece of drywall onto the stud begin to pull out and cause a dimpling look on the drywall surface. Sometimes you can carefully tap the nails back in place, but that might only result in them popping out again later.
For a more permanent fix, insert a couple of drywall screws into the stud about an inch above and below the nail. The screws will attach the drywall panel securely to the stud. At the same time, overly numerous or repeating cracks, deep cracks, and other damage could also be signs of more significant problems you want to address as soon as possible.
Contact us today for a free consultation! The ceiling width is interrupted near one end by the distant partition wall you can see in the left hand photo, but the ceiling continues to open up into another room at that end of the house.
The ceiling crack shown in our photograph at above right occurs almost in the center of this long ceiling run. Because the inch long ceiling is not unrestrained while the coefficients of thermal and humidity expansion and shrinkage are for unrestrained gypsum board.
This ceiling's gypsum board is nailed to the underside of flat roof rafters spaced 16" o. Still we see an ugly wintertime crack in this ceiling and a noticeable summertime crack as well. There is not much point in just taping over this crack without installing control joints in this ceiling. Metal corner beads are more crack and separation prone in drywall installations than plastic tape-on or glue-on using spray adhesive or mud-on corner bead material.
Frost heaving foundations can cause differential movement in building walls that causes severe tearing or cracking in plasterboard, gypsum board, or drywall. Photo above left: shear cracking shows up at the inside drywall corner of two exterior walls of a New York building. This cracking was caused by differential frost heaving. At above right you can see the corresponding crack in masonry block foundation supporting the building walls.
High soil water content, drainage difficulties, and freezing climate explain this damage. In a demonstration that the ceiling crack stress point sketch is not just theory, our photos just above show cracks at the taped intersection of ceiling to partition wall at a natural stress point.
This crack appeared in less than a year after new construction. The underlying cause may have been a combination of framing shrinkage and slight sagging of the supporting floor structure. The wall corner projecting into the room is directly above a stairwell cutout. Floor settlement actually pulled this corner down, separating it from a rigid I-beam roof structure. We will repair this crack by cutting out the separated paper drywall tape and re-taping the joint on both sides of the partition wall corner-to-ceiling juncture.
But this little repair is a bit of trouble as re-painting the ceiling and wall will also be needed. Our photo at left shows the original drywall being installed on the same ceiling as in the drywall tape joint separation photographs above. You can see that the sheetrockers took care to hang a full piece of drywall that extended past the partition wall corner precisely because they knew that this was a stress point.
That detail worked - we did not see a tear in the drywall itself. What did ensue was enough downwards movement to stress and open the drywall tape at the partition wall-to-ceiling joint. Below is a second example of a similar effect.
Here we see a complex soffit structure carrying windows and suspended from a conventionally-framed 2x12 ceiling structure. Here, too, cracks appeared in the ceiling as the structure below moved downwards. Framing flexing - drywall cracks : in interior ceilings or cathedral-ceilings not framed to modern construction standards for stiffness we may see cracks, often at drywall joints, caused by flexing in the ceiling structure. Particularly in some older homes with minimal attic floor framing that was originally intended only to support the weight of a plaster ceiling, we may see ceiling cracks caused by building occupants or home inspectors who clambered around in the attic area above, stepping on framing members never intended to bear their weight.
Details of the coefficients of thermal expansion or contraction and the coefficients of moisture-related expansion and shrinkage of plasterboard are. Below we give several examples of types of building movement traced to settlement and causing significant interior wall or ceiling cracking. Backfill settlement in New York : the photographs below illustrate severe settlement in a New York home.
Unlike the Alaskan house above damaged by construction on thawing permafrost , the home below had been constructed on backfill over a stream bed. Seasonal water flowing below the building appears to have contributed to severe slab and foundation damage that telegraphed upwards through this home as floor-wall separation, ceiling-wall separation, and cracks at windows and doors of the home shows in the photos just above.
By noting the plasterboard crack locations, patterns, angles, and dimensions it was apparent that they all pointed to settlement in the supporting slab. Checking the finished basement floor for level we confirmed that the floor was settling significantly towards the building center. Permafrost settlement in Alaska : The two photographs above show severe plasterboard cracking in the same Alaskan home illustrated at the top of this page.
In the above photo, settlement and drywall tearing cracks appeared at a horizontal drywall joint to the right of a door jamb a poor location for a drywall joint and exacerbated by the use of mesh tape that is not as strong or tear resistant as paper tape. In our second drywal cracking photo just above we see a typical diagonal gypsum board crack extending down and to the left of a window opening.
The window trim has been pulled apart as well. These cracks are not to be blamed on the drywall installation: this home had suffered movement in excess of what plasterboard is expected to endure.
Earthquake damage crack patterns characteristic of the Northridge earthquake in California in January are illustrated by our photo shown at left. This crack pattern appears here in a stucco exterior, but it was duplicated on drywall interiors as well. Even if building temperatures are kept steady after construction is complete, drywall installation temperatures may contribute to subsequent cracks: mudding drywall in cold buildings increases drying times and may increase the crack risk.
Large variations in building temperature or moisture level or both. The majority of the time they are considered cosmetic and can be covered over when repainting is done. These cracks are most commonly seen in areas where the structure develops more stress than other areas.
The most common areas are the corners of doors and windows as well as the corners of wall openings. This is true of both exterior and interior doors and openings. Another common place to see these cracks is where two pieces of drywall come together. These cracks usually run either horizontal or vertical at the drywall seams. Homes with vaulted ceilings may develop these cracks in the higher areas as well.
Additionally, drywall cracks are often found where two pieces of drywall are butted together. This occurs because there is a joint, which gets drywall taped and then layered with two or three coats of drywall mud. These joint areas are weaker than in the center, or field area of the drywall, therefore some cracks may occur at these joints.
As previously mentioned, stress is usually the main reasons that cracks occur. However, there are many potential causes of stress; some of the more common ones are:.
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