Brick Fretting in Perth: Signs, Causes & How to Fix It

Brick Fretting: How to Spot Fretting Mortar Before It Spreads

Brick fretting, where the mortar joints or the faces of the bricks start to crumble away, is one of the most common problems we see on Perth homes. Caught early it’s a straightforward repair. Left too long, it lets water into your walls and can undermine the brickwork itself. Here’s how to recognise fretting bricks and mortar before they turn into a bigger job.

What Is Brick Fretting?

Fretting is the gradual crumbling and breakdown of the mortar joints, or the brick faces themselves, in your brickwork. You’ll also hear it called fretting mortar, fretting brickwork or spalling. As the mortar turns powdery and falls away, the joints lose their strength and their ability to keep water out.

What Causes Fretting Mortar and Bricks?

In Perth, the usual culprits are moisture and the original mortar mix. Common causes include reticulation or garden beds directing water onto the walls, salt and rising damp (especially on older limestone and brick homes), mortar that was mixed too weak or too strong with waterproofing additives that trap moisture in the bricks, and decades of weather exposure on ageing joints. On limestone properties in particular, damp-driven fretting often sits alongside other decay, which is where limestone repairs come in.

Signs of Fretting Bricks to Look For

Watch for powdery residue, that sand or mortar dust collecting at the base of walls. Look for receding joints where the mortar has eroded back between the bricks, and for flaking or loose bricks where the faces are peeling away or there’s movement. Damp patches inside or out are another giveaway, since water is getting through the weakened joints.

What Happens If You Leave Fretting Brickwork?

Once the joints fail, water moves freely into the wall. That accelerates the fretting, can rust wall ties and lintels, and eventually affects the structural integrity of the brickwork. What starts as surface crumbling can progress to cracking and movement that needs crack stitching, turning a simple repointing job into a much larger repair.

How to Fix Fretting Brickwork

The right fix is to rake out the failed joints and repoint them with a mortar matched to your existing brickwork, so the repair blends in and, just as importantly, breathes the way the original did. Avoid DIY patching, as the wrong mortar mix often makes fretting worse rather than better, and act while the problem is still confined to the joints. Our brick repointing service restores the joints properly and matches your existing mortar.

Noticed Fretting on Your Brickwork?

If you’ve spotted fretting mortar or crumbling bricks, get it inspected before it spreads. Contact Mortarfix for a look over your brickwork and a free quote across Perth.