How to repair a leaking bathroom sink

There are several reasons a bathroom sink can leak. One of the most common reasons is that water gets on the counter and seeps through where the bowl attaches to the vanity countertop. Another common reason is that the faucet has become loose and allows water to leak. Both of these problems can be fixed for little money and a small investment of time
Instructions

1. • Tighten the faucet to the sink top by tightening the nuts on the faucet stems under the sink. Use a basin wrench to snug the nuts, but be careful not to over tighten them or the faucet body may crack.
     
     
   • Pour some water at the edge of the sink where it meets the vanity top and inspect under the sink to see if water is leaking through.
     
     
   • Cut out the old caulk from around the bowl with a utility knife if water is leaking from the edge of the bowl.
     
     
   • Clean the area around the bowl completely with mineral spirits on a rag.
     
     
   • Apply the caulk evenly around the bowl where it meets the vanity top. Spread the caulk with a finger to make an even bead that fills the crack between the bowl and the countertop.
     
     
   • Clean any stray caulk on the counter and the bowl with mineral spirits on a rag. Let the caulk dry for 24 hours before getting it wet.