Cracks in walls, crumbling plaster, water pooling beside the walls after it rains and the age of the building itself were all indicators of the likelihood of moisture-related damage hiding behind cement plaster. We started the repair work by removing the flagstone on the east side to allow the ground and the walls to dry out before damage could be assessed.
2/24/17
When a 3’ x 4’ section of plaster was removed, the adobe wall was allowed to air dry. The drying process allowed time for the “salts” to travel toward the surface of the adobe wall and once dry the soft, powdery damaged parts of adobe bricks were scraped off with a hand trowel. This plaster removal and allowing time for the adobe walls to dry out gradually revealed the damage, which had been hidden beneath layers of cement plaster.
An assessment of the east wall of the Guadalupe House revealed: multiple layers of cement plaster had been applied over the years which had created a coat of cement plaster, measuring 2 to 3 inches in thickness. Adobe damage, caused by trapped moisture, was 3 to 6 inches deep in some places. Underlying remnants of mud and lime plaster could still be seen in the oldest layers. The lime plaster layer had been pigmented with a rose color as seen in the Gonzales photo. The original foundation had been built of stones and lime mortar.
Adobe “stitching” technique, small volcanic stones used to anchor lime plaster, first coat of lime plaster