The sill is beveled on one side to drain water away from the house.
Cement door sill replacement.
Most exterior thresholds also have a sill beneath them.
Position the old door sill on the new sill and trace around it.
Door thresholds come in a variety of materials such as wood marble and metal and make the transition from doorway to floor smooth and easy.
If the threshold is rotted the sill probably is too.
Caulk around the outside of the door sill.
Cut the new door sill to size and bevel the outer edge.
It looks like a massive undertaking to replace the whole sill and my new door frame and sill will fit into the opening with merely grinding down the hump on the cement sill.
There are a number of weatherproofing issues we need to address but the most urgent is the concrete sill under the door which has been crumbling for a while and presumably is the source of our leak.
We have a metal threshold over a concrete sill and our front porch is a concrete slab about 4 x6.
If your threshold is in rough shape replace it.
Fit the new door sill in place under the door frame.
Thresholds come in wood and metal both of which come with a rubber gasket for sealing out the cold.
Hold the new door sill in place with construction adhesive and fasteners.
Replace the metal.
Paint or stain the new door sill.