Concrete Chimney Crown Repair

Chimney crowns sometimes mistaken as chimney caps or covers are the slab of concrete at the top of a chimney.

Concrete chimney crown repair. Fixing your chimney crown costs 150 to 300. A solid crown in good repair prevents water damage from. Re cap is designed to repair restore and renew worn or spalling concrete surfaces. A chimney crown is a concrete cap that tops the masonry walls of a brick chimney to shed water and seal the chimney s flue to the masonry.

Silicone sealant should be added to the 1 4 separation to prevent water damage. The concrete crown should not come into contact with the flue. The chimney crown should extend up to a minimum of 2 5 inches beyond the chimney wall and a drip edge should be provided at the bottom of the overhang part of chimney crown. If the flue is at a height less than 6 inches the crown should be built 2 inches from the flue top.

The idea is to have the water drain away from the crown image 1. The thinnest part of precast concrete crowns must be at least 2 inches. If the flue of the chimney is about 6 inches from the top the crown must be made 4 inches from the flue top. Chip off old mortar from the existing chimney crown but using a hammer chisel and wire brush.

See if the cement holds to the chimney body and then apply more of the mix. When applying the mortar to the crown form the mortar into an apex with the peak at the middle of the crown sloping down toward the edges. Take up this mixture of concrete and apply on the chimney around the flue in place of the detached crown. Build your cap frame use 2x4 lumber to make your new concrete form.

Chimney crown repair cost. The crown should be made of concrete only and mortar should not be used. I show you all the steps i used chipping out the old crown cutting plywood if you are worried about moisture use 1 2 hardie bac. It is designed for making a thin layer of repairs to and restoring the appearance of existing sound concrete surfaces.

To avoid bonding problems between old brick and new concrete be sure to clean off all dust and debris from the old brick. Diy chimney crown repair. During construction the flue should be wrapped with a compression material to allow a 1 4 separation between the concrete crown and the flue tile.