Page 179 - Masonry and Concrete

Masonry Construction Techniques
178 CHAPTER FIVE

moist curing. Extreme winter conditions may also require the applica-
tion of heat inside these enclosures to maintain temperatures above
40°F. Even though concrete masonry units cannot be wetted on site
before they are installed, completed concrete masonry walls can be
moist-cured because the restraining conditions of the joint reinforce-
ment and surrounding construction minimize the effects of moisture
shrinkage in the units.

5.8 Cleaning Masonry

Cleaning new brick and concrete masonry is easiest if some simple
protective measures are taken during construction. The finished
appearance of masonry walls depends to a great extent on the attention
given to the surfaces during construction and during the cleaning
process. Care should always be taken to prevent mortar smears or
splatters on the face of the wall, but if such stains do occur, proper
cleaning can help prevent permanent discoloration.

5.8.1 Construction Precautions
Precautions which should be taken during construction include the
following:

■ protecting the base of the wall from rain-splashed mud or mor-
tar droppings by using straw, sand, sawdust, or plastic sheeting
spread out on the ground and up the wall surface;

■ turning scaffold boards on edge at the end of the day to prevent
rain from splashing mortar or dirt directly onto the wall;

■ covering the tops of unfinished walls at the end of the day to
prevent saturation or contamination from rain; and
■ protecting masonry units and packaged mortar ingredients from
groundwater or rainwater contamination by storing off the
ground, protected with waterproof coverings.

5.8.2 Methods of Cleaning

The cleaning process itself can be a source of staining if chemical or
detergent cleansing solutions are improperly used, or if windows,
doors, and trim are not properly protected from possible corrosive

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