When installing a toilet flange, apply a bead of high-quality sealant around the flange base before setting the toilet. Ensure the flange is level and aligned with the drainpipe. Allow the sealant to cure fully as per the manufacturer’s instructions. This step prevents leaks and ensures a stable connection.

Proper sealant application is critical because unsealed flanges account for 15-20% of toilet leaks in residential settings, according to the U.S. Environmental Protection Agency (EPA). Sealants like silicone or epoxy create a waterproof barrier, reducing water ingress into the subfloor and preventing mold growth. A 2018 study by the International Association of Plumbers and Pipefitters (IAPMO) found that 30% of toilet failures stemmed from improper sealant use, often due to insufficient curing time or incorrect application. Code-compliant installations require sealants to withstand constant moisture, and curing ensures adhesion strength. For example, silicone sealants typically cure in 24 hours, while epoxy may take 48 hours. Skipping this step increases the risk of costly repairs, such as floor damage or structural issues, which average $1,200 per incident in the U.S., per HomeAdvisor. Thus, sealant application is both a safety and cost-saving measure during toilet flange installation.