Tuckpointing the chimney on your home in North Bay Village

Joint conditions that call for repointing

Brick industry maintenance guidance lists the joint conditions that usually call for repointing. We look for each of them on every face of the chimney.

When a face shows these conditions, we mark the area and explain whether the damage is local or spread across the chimney. The pattern also hints at where water is coming from.

• Mortar eroded back from the brick face
• Mortar that crumbles or has voids
• Hairline cracks through the joints
• Cracks where mortar has separated from brick

Bonding agents are not a shortcut

Some repair products promise to glue new mortar to old joints. Federal preservation guidance says bonding agents are not a substitute for proper joint preparation and should generally be avoided. They are also hard to remove if smeared on the brick face.

A properly raked, cleaned and dampened joint bonds without them. We rely on preparation rather than additives. If an earlier repair on your chimney used a bonding product, we note any staining it left and explain whether it affects the new work.

Hardness is not the same as permeability

A mortar can feel hard and still let moisture pass, and a softer one can be dense. Federal preservation guidance notes that softness or hardness is not necessarily an indication of permeability. Old lime mortars can be hard and still breathe.

That is why we look at the brick and the existing mortar together rather than scratching a joint and judging by hardness alone. The goal is a new mortar that lets the wall dry through its joints and stays the weaker partner to the brick.

Covering the flue when the cap comes off

Repointing the top courses sometimes means lifting the rain cap for access. That leaves the flue open to rain and debris while the work continues.

Whenever the cap is off and we stop for the day, the flue opening gets a cover until we return. The cap goes back on once the top joints are finished. If its fixings are worn or the cap is damaged, we tell you, and replacing it is priced as a separate item. The joint scope itself does not change because the cap came off.