Can I apply stucco over a block, brick or concrete wall without applying a cement plaster base coat?
ยป This is not recommended, a minimum 3/8″ brown coat of Portland cement plaster applied to the wall prior to the Stucco Color Coat reduces the possibility of the grout lines telegraphing through the Stucco Color Coat. The brown coat properly prepares the surface making it more receptive to the color coat application; additionally it levels the wall for a straighter and more attractive wall. If the block, brick or concrete wall has been painted or sealed, either remove the paint/sealer or mechanically attached lath, then apply a portland cement plaster base coat, moist cure and allow to dry prior to the Stucco Color Coat.
