CrownSaver™ Crown Repair System from
When the crown is gone beyond the point of simple repairs, use CrownSaver to build a new one. It has a 10-year warranty. Comes in 30 lb. buckets with directions right on the side.
This is a dry product which you mix with sand (one scoop of CrownSaver to 3 scoops of sand--scoop provided) and water. Can be used with or without FormFoil, an aluminum foil backed adhesive that is pressed in place over the existing crown, (FormFoil acts as a bond break and watertight flashing system between the old and new crown) or pull the old one off and build the new one from scratch with just the CrownSaver.
You can apply over the old crown, no forms are needed and it sets up in under two hours. Because it's from SaverSystems (the same folks who produce Chimney Saver) it contains waterproofing, the perfect product for crowns!