Division 4 - Masonry
Cleaning
To begin with, it is currently our policy to limit the use of pressure washing masonry. The
primary reason for this is the fact that in the past, cleaning contractors use the pressure washing
to remove excess mortar that needs to be scraped off by hand. The end result of this is typically
blowing mortar out of head and bed joints and breaking the smooth finish of the mortar joint
allowing more water to enter. THIS PRACTICE IS TO BE PROHIBITED.
It is recommended this issue be discussed both at your preconstruction conference with the
mason and then again once cleaning is scheduled to begin. The cleaning contractor is usually a
subcontractor of the mason and you must require him to be present when this discussion takes
place. All too often your mason is complete and has left the project leaving his sub on his own.
Subs of subs still need to be supervised.
The proper method is to use a scraper by hand to remove mortar droppings and ribbons left
from tooling of the joints.
While masonry is underway, your masons should brush down in place masonry as work
progresses. This is usually done after the joints have been struck and the mortar is still green
enough to be easily removed. It’s part of the individual bricklayer’s job to do this as he goes.
Improper cleaning of the brick can make a good job appear bad and mistakes made during this
operation are difficult to correct.
Common mistakes made when cleaning;

Too high of a concentration of cleaning fluid (acids or strong detergents) Excess cleaners
will stain the masonry surface permanently. Walls should be full saturated with water
prior to chemicals being applied.

Improper protection of adjacent surfaces. Finishes such as Aluminum window frames,
Finish Hardware, Plates for electrical devices, copper flashings and copings, Stainless
Steel, Brass hardware and similar metals will be destroyed if not protected from the
cleaning agent. Most of these agents contain Muriatic Acid. It is very caustic and
corrosive.

Leaving the cleaning agent on the masonry surface too long. This will also permanently
discolor the mortar and even etch the masonry unit itself. The whole purpose of the
agent is to remove mortar stains on the surface of the masonry. It is allowed to be on the
surface of the wall only long enough to loosen the staining and then must be thoroughly
flushed from the wall. If not completely rinsed off, staining will appear soon after.

Failure to protect the lower wall surface from mud splatters once cleaned. It’s a good
idea to have some landscaping straw on hand to place on the adjacent ground prior to
cleaning or immediately following.
Samet Corporation | Building Structures. Building Relationships.
Division 4 - Masonry
Cleaning

Failure to protect grass surfaces and shrubs from cleaning agent spray. Shrubs and grass
will die if they are sprayed with these cleaners.

Spills on adjacent concrete surfaces will stain if the cleaning agent is spilled and not
immediately flushed with water.
Samet Corporation | Building Structures. Building Relationships.