Masonry Magazine August 2014 Page. 22
MAS5308_August2014_MAS 7/22/14 9:41 AM Page 20
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MANUFACTURED STONE
CalStar Chiseled Cast Stone Unit
come into contact with the face of the
finished stone, do not wipe the mortar CalStar is expanding its line of cast stone products with a 24-inch�
off. Doing th.is will cause the mortar to
long (nominal) unit with a chiseled
smear and will make the removal
appearance that emulates natural,
process harder. Wait until the excess
cut limestone. mortar dries to a crusty consistency, and The chiseled-texture units have a
then flake it off using a soft bristle brush. bed depth of four inches (nominal} and are available in four heights:
Do not use a wire bristle brush, as this
four, eight, 12 and 16 inches (nom�
will damage the face of the stone. Do
inal). CalStar's cast stone starts
not allow the mortar to completely dry
with molds mastered from real on the face of the stone. Ifthe mortar is stone, contributing to an authentic allowed to completely dry, you will not look. By using several different faces per size and an alphanumeric
be able to remove it
installation guide inscribed on each
Douglas: Not all manufactured stone
piece, CalStar ensures installers
products are made the same way. Some
can place the units in patterns that are not repetitive to the eye. The CalStar staff will are colored integrally with mineral assist designers with developing an Installation hierarchy. In addition, units are avaiJ�embellishments mixed throughout the able with a chiseled end for use in comers.
Unlike some products, the units are suitable for at-grade applications and, therefore,
stone, while others tend to hold color
eliminate the need for starter courses. Other uses Include band courses, wainscoting
just at the surface (post-cast applica�
and window accents.
tion). In cleaning these two different
The cast stone products are made with CalStar's process that incorporates up to 18 types, one has to be much more delicate percent recycled content and eliminates the need for Portland cement, used to bind with a surface applied colorant, as both concrete masonry products;for calcium silicate materials, which require energy-inten�
sive autoclaving; or for kiln-firing, typical of traditional clay brick. As a result, each prod�
chemical bleaching and wand pressure
uct requires less energy to make as well as having a lower carbon footprint. The
are likely to facilitate its partial removal
chiseled-face units are available in any of CalStar's monotone colors.
Morris: One of the biggest cleaning
For more information, visit www.calstarproducts.com.
issues with manufactured stone is this: If the stone is not integrally colored, ifa cleaner is used that is to aggressive, then the color can be removed So care must be taken to determine whether the stone isintegrally colored, or if it has a Portland cement colored finish on the surface.
Masonry: Howdo youdetermine pressure and vol�ume for each project? What about accessories, like brush types?
Baer: Because most of the coloration, beyond just the base color of the concrete ( which provides the individuality of each stone and the interest ofthe instaUation) is on the surface of the stone, great care needs to be taken to preserve the exposed
Even when applying stone from the top down mortar will lneYitahly find Its way to
color. New stones, as well as existing stones, should be cleaned
the face of the adhered veneer, requiring cleaning. lbis also especially occurs
with special-purpose manufactured stone cleaner. Ifyou are when grouting a stone profile that's not stacked. going to use a pressure washer to wash the brick, unless you are using a Kem-0-Kleen masonry cleaning machine, you should I've seen plenty of good-looking manufactured stone ruined not use the washer to apply the manufactured stone cleaner. with a metal bristled brush in haste. Though it contains only a small percentage ofacid, the acid will Morris: Minimum pressure must be used, ifany, on manu�deteriorate the water pump, hoses and wand. When using any factured stone. Ifa brush is used, it must be a natural masonry pressure washer, the pressure needs to be minimal It would be brush designed to be used on mortar. The use of wire or a advisable to use a 40-degree water nozzle to assure there is not brush that is too stiff can cause damage to the stone. excess pressure and the wand is held away from the work.
Douglas: As with most masonry, the rule is "as gently as we Masonry:Why is anunderstclllding ofthe reaction
can to achieve the desired result:' I approach from this philos�
ofthe cleaner on the manufactured stone and its
ophy with regard to both chemical dilution and machine pres�
components important?
sure, or whether I decide to use a low-pressure washer at all. Sometimes a bucket, brush and garden hose work just fine. Baer: It is important to remember that even ifthe high And, as for brushes, always use a light nylon or natural brush. pressure water sprayer is rated at 3,000 psi -a typical rating for
20 MASONRY � August 2014 � www.masoncontractors.org The Voice of the Masonry Industry