Lathing in Albuquerque, NM

Lathing is the part of a stucco job nobody sees once it is finished, but it is what everything else depends on. A weather resistant barrier, usually building paper or a synthetic wrap, goes over the sheathing first, lapped correctly so water sheds down and out rather than working its way behind it. Metal lath is then fastened over that barrier, furred slightly off the wall so the stucco has room to key into it instead of just sitting flat against the surface.

The details that matter here are easy to miss but hard to fix later, since they end up buried under the stucco. Barrier laps have to run the right direction, lath has to be the right type for the job and fastened with enough spacing to hold the coats without flexing, and casing bead has to go in clean around windows, doors, and edges so the stucco has a finished line to stop against.

A wall with the wrong barrier lap, or lath that was stapled flat instead of furred, will look fine the day the stucco goes on. The problems show up later, as stucco that cracks along the fastener lines or pulls away from the wall instead of holding tight.