The Problem
The owner of a 1952 brick bungalow on a Central Norridge residential block noticed mortar crumbling along the front and side facades. Joints on the north elevation were the worst - recessed nearly a half inch in places and showing surface cracking across most of the wall. Several joints near the limestone window sills had failed completely, and water staining on the limestone surface suggested moisture was working its way into the sill seat.
The limestone sill course was original to the home. The mortar at the limestone-to-brick interface had failed along both front windows, creating a gap wide enough for water to pool against the sill base. That water, once inside the sill seat, was a direct path into the window rough opening above.
Our Solution
We removed deteriorated mortar to a uniform depth of 3/4 inch across all four elevations using angle grinders fitted with diamond blades set to a controlled cutting depth. At the limestone sills, we used a narrow oscillating tool along the sill interface rather than a grinder to avoid scoring the stone face.
The replacement mortar was Type N - the correct specification for this era and brick type. We pulled mortar color samples from a protected joint on the interior chimney stack, which had not been exposed to weathering. The final sand selection matched the original warm gray tone closely.
All joints were packed in two lifts per joint, with a firm-up period between lifts. At the limestone sill interface specifically, the joint was tooled with a recessed wash profile rather than the standard concave tool used on the field joints - this profile encourages water to shed forward off the sill nose rather than sitting against the limestone-to-brick interface.
The Result
All four elevations were completed in four days. The limestone sill joints are sealed and profiled for drainage. The mortar color is consistent with the original joints visible in protected areas under the front porch soffit.
The homeowner now has a complete mortar record for the home, including the sand color and Type N blend used, so any future spot repairs can be matched.
