How to Best Avoid Drywall “Button Pops”
Using two separate testing methods, Franklin International measured the relative changes that occur with wood framing, metal framing, drywall and drywall adhesives in four different environmental conditions. Our test results showed there is not a single cause behind buttons and pops, but a combination between seven key factors, with wood moisture content being the biggest contributor:
- above 10% moisture content of the stud wall or ceiling joist
- adhesive shrinkage (whether water- or solvent-based)
- drywall shrinkage
- type and length of fastener
- technique used in setting the fastener
- changes in climate
- faulty workmanship
Our study found no distinction between water-based and solvent-based adhesives in regard to shrinkage; both adhesive types shrink and pull the drywall toward the stud. The reason adhesive was introduced into the drywall process was to reduce the number of fasteners needed in the job, which would reduce the number of pops, finish time, and potential for sag.
Based on our findings, we recommend your customers take these steps to reduce the risk of buttons pops:
- Use a moisture meter to determine moisture content of the wood framing before drywall installation. If the wood is above 10% wood moisture content, let it dry before installation.
- If finishing cannot wait, use a polyurethane-based adhesive to reduce the contribution of solvent- or water-based adhesive shrinkage to movement and eliminate water absorption from water-based adhesives. Polyurethane adhesives do not shrink or contain water.
- Use the shortest fastener recommended by the drywall manufacturer. The longer the fastener, the greater the relative movement of the screw head to the wood stud surface.
- Install a properly seated fastener with a dimple that doesn’t break the paper. Overdriving the fastener to the point of breaking the paper will cause more movement.
Read more about our testing procedures and outcomes in a detailed summary of our technical report.