Sunday, November 29, 2009
When I install an attic ladder in a lath & plaster ceiling, I have an added patching job if I have replaced a larger ladder. In this case of a new ladder installation, there might have been little or no patching. However, the ceiling was cracked and detached from wood lath near a decommissioned chimney. I liberally pulled off loose plaster to allow reset of wood lath, adding new wire lath where possible.
The wire lath is strongly attached with screws. All edges are fully bonded with flexible grout, applied to surfaces very wet from water spray. As in small-crack repair, the grout flows best with local dilution. Plaster can not flow into thirsty edges. Edge preparation with Plaster-Weld adds no mechanical strength or restraint of wire-lath ends.
Here, all wood lath and broad original plaster surfaces are coated with Plaster-Weld bonding agent, applied by brush.
The patch of Structo-Lite Basecoat Plaster is applied in two steps. Here a good match of surrounding texture was achieved by simple striking with a 4-ft Feather Edge. Dark detail in the patch is spot application of flexible grout to correct under-fill or to add texture.
Please note the ladder appearance, blending with the ceiling, never using trim molding. All ladder frame edges are bonded-in with flexible grout, fairing in a very uneven plaster surface. With best fit of the ladder frame, level, the ladder frame is about 1/8" proud of plaster along the hinge end, and about 3/16" recessed from plaster at the center of the near long edge. Molding is needed by anyone else, lacking flexible grout. Molding can never be relied-upon to seal clearances between the ladder frame and the ladder rough opening.
The ladder is a rugged and simple Calvert Model 1026. My trademark safety pole with hand grips is visible through the opening.