Why Is My Home's Brick Exterior Showing Spalling From Moisture?

Last updated October 25, 2026

The short answer

What Causes Brick Spalling

Brick is porous, so it absorbs water from rain, snow, and even humid air. When that water freezes, it expands. Over many freeze-thaw cycles, the pressure pushes off the outer face of the brick, leaving pits, flakes, and a rough texture.

Moisture can also come from behind the brick, such as from a leaking roof, gutter, or pipe. Salt from de-icing products or in the water can speed up the damage. If you notice white stains or crumbling surfaces, moisture is the likely culprit.

Cracks or chips on brick faces
White or gray efflorescence stains
Soft, crumbling areas that flake off
Damp spots on interior walls near the brick
Water pooling at the base of the wall
Moss or algae growing on the surface

How to Spot Moisture Entry Points

Check the obvious places first. Look at gutters and downspouts for clogs or leaks that dump water onto the brick. Inspect window sills, door thresholds, and flashing for gaps. Also look for cracked mortar joints, which let water seep in easily.

Inside your home, feel for dampness on walls that share the exterior brick. A water meter or a moisture inspection can help pinpoint hidden leaks. A wet basement wall often points to drainage problems outside, especially after heavy rain or snowmelt.

Steps to Prevent Further Spalling

Act quickly to reduce moisture. Clean gutters, extend downspouts away from the wall, and grade soil so water drains away. Seal cracks in mortar with a breathable masonry sealer, but avoid plastic paints that trap water inside the brick.

Reduce humidity in your home with a dehumidifier, especially in basements. Keep snow from piling against the wall for long periods. If you have a sprinkler, aim it away from the brick to limit water exposure.

When to Call Local Water Damage Pros

Spalling is more than a cosmetic issue. If bricks are flaking deeply or mortar is crumbling, the wall's structure may be weakened. In that case, you need a professional assessment to decide whether to replace bricks or just repoint the mortar.

Local water damage pros can test how wet the wall is and find the source of the moisture. They can also dry out the structure and advise on repairs. For older homes, a historic home specialist may be a better fit to match materials.

Repair Options for Damaged Brick

If the damage is minor, you might only need to remove loose flakes and apply a breathable masonry sealer. But if bricks are structurally weak, they must be cut out and replaced. The cost depends on how many bricks are affected, the type of brick, and the labor involved.

Mortar repointing is often part of the fix. A pro will rake out old, crumbling mortar and refill the joints with a mix that matches the original. This helps keep water out while letting the wall breathe.

Water damage does not wait

Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.

Call Now (313) 766-2970

Frequently asked questions

Can spalling brick be repaired without replacing the whole wall?

Yes, if the damage is limited to the surface. A pro can remove loose brick and repoint mortar. But if many bricks are crumbling, replacing them is safer. The extent of the damage decides the approach.

Does sealing brick help stop spalling?

A breathable sealer can help by reducing water absorption, but it won't fix existing damage. Avoid non-breathable coatings that trap moisture. Fix the water source first, then seal.

Is spalling a sign of a bigger foundation problem?

Not always, but it can be. Spalling at the base of a wall often means water is pooling near the foundation. Check for cracks in the foundation and poor drainage. A water damage inspection can tell you if moisture is coming from below.