Failed chimney bricks replaced with care in Cheval

What white deposits on the chimney tell you

Efflorescence is the white bloom that salts leave on brick. The Brick Industry Association says it takes three things together, namely salts that can dissolve, water that stays on them long enough to dissolve them, and a route through the masonry that carries the solution out to the face.

Efflorescence can usually be removed by dry brushing, and BIA advises against washing it off except in warm, dry weather, since the extra water can bring more salts out. More important than removing it is asking why it keeps coming back, because persistent efflorescence points to water still getting in.

We note where the deposits sit and trace them back toward the source during the inspection.

Mortar that is harder than the brick

Mortar is meant to be the weaker, more permeable part of a brick wall. The National Park Service explains that repointing mortar should be softer and more vapor permeable than the bricks, and that mortar stronger than the units can cause damage such as cracking and spalling.

When hard mortar surrounds softer brick, moisture and movement stresses end up in the brick instead of the joint. Replacing bricks in that situation without addressing the mortar can repeat the damage.

We compare the existing mortar and the bricks before choosing the repair mortar, and explain the choice on the estimate.

Deciding how many bricks to replace

The repair area is set by the condition of each brick and the masonry around it. Isolated damaged units in sound surroundings can usually be replaced one at a time. Clusters of failed bricks, or failed bricks alongside worn joints, can call for a larger section.

We mark the units that have failed, note the ones worth watching and explain the difference. The goal is to keep every sound brick while removing every one that will not last.

The estimate shows the number of units or the area involved, so you can see how the price relates to the work.

White bloom on newly repaired brick

Fresh masonry can show a light white bloom in the first months after a repair. The Brick Industry Association calls this new building bloom and notes that it generally fades as the new work dries and weathers.

Efflorescence that appears more than a year after work is finished is a different signal, which BIA links to excessive water penetration or poor drainage. If white deposits come back strongly after the first year, call us for another look.