Stucco cladding

Stucco was used as a cladding on some architect-designed homes in the 1970s.

Stucco is a cement-plaster coating to walls. It was not commonly used on builder-built houses during the 1970s, but may have been used on architect-designed houses.

Stucco was also sometimes installed over an existing older timber weatherboard or asbestos-cement cladding.

Construction details

Stucco should consist of a 1:1:6 cement:lime:sand mix, or a 1:½: 4 ½ cement:lime:sand mix, which is applied over galvanised wire netting or metal lath reinforcing fixed over a rigid or a non-rigid backing material.

Lath

The wire netting or metal lath is fixed approximately 5-10 mm clear of the backing. Three coats of plaster are applied to give a finished thickness of around 22 mm.

Backing material

The rigid backing board could consist of asbestos-cement sheet or 200 mm wide x 18 or 25 mm thick close-boarded timber.

The non-rigid backing material could be a heavyweight building underlay or a bitumen-impregnated felt installed over galvanised wire netting to support the paper.

If a rigid backing board was used, building paper was installed over the backing to provide a slip layer.

Window and door openings

Window details in stucco cladding typically incorporated back flashings to the jamb and sill. For timber windows, the flashing was incorporated into a saw cut in the timber jamb.

In his 1970 imperial edition of Timber framed construction, RJ Willson only gives timber window details.