The process of running a sealant bead might look simple, but there’s plenty of skill and experience that goes into doing it right. And for all tradesmen, regardless how often they use sealants on the jobsite, proper application is required for ensuring good, long-term performance. Sealants are often the first line of defense against the elements, and avoiding these top five mistakes will ensure better results.
Sealant performance relies on good adhesion to different surfaces, high flexibility and long-term durability. Accomplishing optimal results requires sufficient sized bead application – especially in external applications. With the exception of hybrid formulas, most sealant technologies will shrink as they cure. In fact, the bead applied can reduce in size by up to 30% with some acrylic or solvent based formulas. This needs to be considered when sealant is being applied on the job site.
Small and thin beads may not have enough surface contact and may lack the necessary volume or body to endure cyclical or seasonal movement of some substrates. Since sealant is exposed to the elements year-round, the durability of small beads can break down after long-term exposure. Contractors should check local building codes and material installation instructions before running a bead. It’s recommended that exterior fillet & bedding beads should be 3/8” in thickness with interior trim beads being no less than ¼".
Sealant belongs on the wall, not in the trash. There are some sealant cartridges designed with a removable tip, which helps prevent waste in two major ways. The first happens when the plunger of the caulk gun has been completely depressed, and yet there is still perfectly good sealant remaining in the end of the tube and in the tip. With no way to extrude the material any further, installers are often forced to toss out the tube with product still inside. A removable tip allows the transfer of that remaining sealant to the next tube without any product loss – and with the added benefit of maintaining the angle, shape of the tip cut and bead shape.
The second waste reduction factor happens at the end of the day or job. For any cartridge that is still half full, there are methods for preventing the sealant from curing in the tip, but they have time limitations. Once the sealant has cured in an unremovable tip, there’s no way to save the material left in the tube. If that same cartridge has a removable tip, it can be replaced, allowing contractors to extrude all the material that’s still inside.
There is rarely a one size fits all solution in the sealant category. Construction sealants come in a wide variety of formulations that are designed for specific uses. Not all sealants adhere equally to different materials. They have different performance characteristics that are better equipped to handle certain weather and climate conditions or specific application requirements.
An SMP or hybrid formulation can typically provide contractors with all-around great performance. If other sealant technologies are being considered, research their full capability before deciding. At a product level, contractors should consider reviewing product TDS, brochures and packaging information before making a purchase. OSI also provides additional resources to help pros find the right sealant for their jobs including this comprehensive article: Choosing A Construction Sealant Technology.
Sealant beads are frequently applied in a way that can prevent drainage. This traps moisture and can cause significant damage to windows, doors or wall systems. Pros can inadvertently seal up built-in weep holes or forget to run a discontinuous bead at the window sill. Oftentimes this happens by accident, but it can also be a result of insufficient knowledge or training in proper sealant and flashing techniques. To help prevent this from happening, OSI has a variety of resources to help ensure proper sealant application including a comprehensive installation guide and online training.
For most sealant technologies, tooling decreases the performance of a product. If you remove or thin out the material too much, a sealant loses its bond strength to the adjoining surfaces. It can be more susceptible to UV exposure resulting in discoloration. And tooled beads often lack the volume, as previously noted, to endure long-term expansion and contraction from seasonal climate shifts.
Many manufacturers of construction sealants have installation guides and best practices to assist contractors. The Best Practice Use Guide for QUAD MAX, is an excellent resource from OSI to support pros in the field.
As a pro, you need things sealed right the first time on the job site. That’s why pros who know use OSI construction sealant products. See our full collection of sealant products designed to perform and stand up to the harshest elements.
Disclaimer: the information provided is intended to offer a general understanding. OSI recommends you seek out technical data sheets, speak further with an expert and/or gather additional performance information before making any final product decisions.
