Chimney Crown Repair for the Valley's Older Brick Chimneys

Short answer: a crown with hairline cracks can usually be sealed with a flexible crown coating; a crown that is broken through, loose or built from a thin smear of mortar has to be recast. HomeGuide's 2026 cost guide puts chimney crown repair at $150 to $1,500, and the free inspection tells you which end of that range your chimney falls in.

Crowns are a brick-chimney problem, so they matter most where the brick chimneys are. In the Census's 2020–2024 estimates, 42% of Phoenix homes and 41% of Tempe homes were built before 1980, along with 35% in Glendale, 29% in Mesa and 89% in Sun City. Homes built after 1998 almost always have a factory-built fireplace in a framed chase, which is topped with a metal chase cover instead of a crown, so if your house is newer, the chase cover page is the one you need.

Signs you need this

• Cracks across the top slab you can see from a ladder or in roof photos
• Gray crumbs and broken bits on the tiles below the stack
• Puddles on the firebox floor or a wet, rusty damper after storms
• Dark, wet-looking brick on the upper courses after rain
• A top slab cut flush with the brick, so rain runs straight down the face

How we do it

1. Photograph the topWe go up on the roof, measure the crown, and photograph cracks, missing pieces and how the slab meets the flue tile.
2. Decide seal or recastSound crowns with fine cracks get cleaned and coated. Crowns that are loose, crumbling or too thin are taken off.
3. Form and pourNew concrete is formed to stick out past the brick with a groove underneath, so rain drips off instead of running down the face, and a bond break lets the flue tile expand on hot days.
4. Reset the cap, look at the flashingBefore we leave, the cap is reset or replaced and the flashing below is checked, since water often uses more than one path.

Why Valley crowns crack without freezing weather

Phoenix averages about one night a year at or below freezing (NWS normals for Sky Harbor), so the classic freeze-thaw story from colder places does not explain most cracks here. What we usually find is a crown built as a thin mortar wash rather than a real concrete slab, a slab poured tight against the flue tile with no room to move, and decades of daily heating and cooling in a climate that averages 111 days a year at 100°F or more.

Once a crack opens, monsoon rain from June 15 to September 30 does the rest. Water that reaches the inside of the brick rusts the damper, stains the firebox and loosens the mortar joints at the top of the stack.

Seal, recast or rebuild?

Most crown work falls into one of three bands, and we show you the photo that puts your chimney in one of them.

• Fine surface cracks, slab still solid: clean and apply a crown sealer
• Broken, loose or very thin crown: remove and cast a new one with an overhang
• Loose brick below the crown: the top courses are rebuilt first, then the new crown goes on, which falls under brick chimney repair

Three parts people mix up on the roof

Mixing these up leads to wrong quotes. On masonry, the poured slab across the top is what this page is about. Above the flue opening sits a separate metal hood with mesh that blocks rain, birds and blowing debris. On a newer home, a stucco-framed box around a prefab flue gets a sheet-metal lid in place of a slab. Masonry wants a solid slab plus a hood; a framed box wants a solid lid plus a hood.