ways to keep water from coming in under house
Because this is an entrance door, you may want paintable caulk so that you can make it blend in with your doorframe later. Remove the old door sweep or bottom weatherstrip from the bottom of your door. Both are types of seals that, among other things, keep water from coming in under your door. Door sweeps typically screw to the inside of your door, so use a screwdriver to remove the sweep. The weatherstripping style can be removed by sliding a screwdriver underneath and prying it.