Chimney Repointing & Mortar Joint Repair in the DC Metro Area

From baffles to corbels and parging, the field of chimney repair and maintenance has some interesting terminology. Some, like a chimney sweep, are self-explanatory. Others, like chimney repointing, aren’t as easy to figure out. Why would you need to repoint your chimney? What was it pointing at in the first place?

Here’s everything you need to know about chimney repointing and mortar joint repair, and why repointing is a great option for improving the appearance and structure of your Howard County home’s chimney.

What Is Repointing?

The main purpose of a chimney is to vent combustible products, such as the fumes from a gas fireplace, out of your home. Key to maintaining the integrity of your home’s chimney, repointing is simply a process that replaces the outer part of the mortar that holds the chimney’s bricks in place. Repointing focuses on the outer layer of mortar, because that’s the part directly exposed to the rain and snow, which causes the mortar to crack.

What Is Mortar Joint Repair?

Often used interchangeably with repointing, mortar joint repair (also known as tuckpointing), repairs or refills mortar joints in the brick. The term comes from the action used to pack or “tuck” the mortar into the damaged joint. The tool used to complete the repair is called a “tuck pointer.”

Signs Your Chimney Needs Repointing/Mortar Joint Repair

Chimneys often look great to the untrained eye, but a professional can quickly pinpoint problems like masonry cracks and water damage that can lead to expensive repairs if not addressed in time. Signs your home’s chimney needs repointing/mortar joint repair include:

  • Discoloration. If the mortar has changed color since it was first applied, it could be a sign of weathering and deterioration. It might also indicate a prior, improperly done repointing.
  • Flaking. As mortar weakens, it starts to flake. When you notice mortar pieces that have fallen off, it’s a sign the mortar is unable to hold itself together, which is itself a sign that the mortar will soon be unable to safely hold the chimney together.
  • Cracking. Even the smallest of cracks can result in major structural problems.

If you delay checking or repairing the chimney’s mortar for long enough, the bricks will eventually become loose. Once that happens, they’ll need to be rebuilt. Plus, once the mortar between the bricks begins to degrade, water can seep between the bricks, causing them to swell and crack even more.

What’s Involved in Repointing?

The Howard County area is known for its unique and unpredictable blend of weather. As winter approaches, rain turns to sleet and snow, followed by welcomed sunny winter days. The combined effect of these weather conditions, though, is water expansion and contraction that causes enough damage to the mortar for it to need repair.

Proper repointing is a four-step process that is best done by a professional:

  1. An assessment is made to determine the extent of the mortar damage and how to remove damaged joints without causing new damage.
  2. Mortar joints are removed to the appropriate depth and the new mortar is mixed.
  3. The new mortar is placed between the bricks by layering, compacting, and tooling.
  4. A waterproof sealant is applied to prevent water from permeating the chimney.

Though well-done mortars can last up to 25 years before repairs are needed, all masonry requires repointing at some point. As chimneys are particularly vulnerable to water damage, it’s important to invest in regular chimney maintenance and keep your repointed chimney in good shape.

If you live in Howard County, Potomac/Chevy Chase, or the McLean, VA area and have a chimney that needs inspection and/or repointing, contact us today online or call us at 301-761-2228.