Chimney masonry repair for Pebble Creek homes

Repair mortar for older chimney brickwork

Before the early 1900s, BIA notes, mortar was mostly lime, with little or no portland cement. Those mortars are much softer than modern mixes.

Repairing older brick with a modern high-strength mortar can concentrate stress in the brick and cause spalling, BIA warns. Type O is often used on older brickwork, while Type N may suit newer brick. That is why the age of the brick matters as much as its color when a repair mix is chosen.

Our crew looks at the age and behavior of your chimney's mortar before choosing the repair mix, and explains the choice.

Removing old mortar without chipping brick edges

Power grinders cut mortar fast, and they can nick brick edges and widen joints just as fast. The National Park Service shows how mechanical grinders can chip the edges and corners of older bricks.

BIA adds that a grinder cannot clear the short vertical joints to full depth without cutting the brick beside them, so those are finished with a chisel. Chipped edges also make the joints look wider, which changes how the chimney reads long after the mortar has weathered in.

Our crew chooses tools joint by joint and uses hand tools where the brick is soft or the joints are thin.

The crown above the repaired masonry

The crown is the chimney's roof. Florida's residential code wants it made of concrete, metal or stone, pitched so rain runs off, finished with a drip edge and separated from the flue liners by a caulked bond break.

A cracked or flat crown sends water straight into the courses below it, which is often where masonry damage starts. BIA also warns against feathering a cast crown thin at its edges.

We inspect the crown with every masonry job and price any crown work as a separate line.

What your chimney masonry estimate should show

A masonry estimate is easier to trust when it answers specific questions about the work. Ask any contractor, including us, to spell these out.

• Which areas of the chimney will be repaired, and which are sound?
• Which bricks will be replaced, and which joints repointed?
• Which mortar type will be used, and why?
• How deep will old mortar be removed?
• How will the joints be finished, and how will the color be matched?
• What is being done about the crown, the flashing and the water source?