| Go with
the Flow: Incorporating Cracks into Your Work
by
David Thompson
There are two basic approaches to incorporating cracks
into the design of a cementitious floor: highlighting
them and hiding them.
One ever-popular way to hide cracks is to conceal them
as grout lines in a flagstone pattern.
Tom Ralston of Tom
Ralston Concrete in Santa Cruz, Calif, used this camouflage
concept while resurfacing a residential
driveway with a few long, deep cracks running through
it. Ralston filled the cracks with a flexible caulking,
which he dusted with sand for a groutlike look. Then
he applied a 3/8" cernentitious overlay along one
side of the filled cracks, forming 2- to 3 -foot wide
bands of topping along the cracks. With a stick, he carved
through the wet topping down to the slab, creating additional
grout lines and forming faux flagstones. He colored the
flagstones with earth-toned dry-shake colors, then sealed
them. He covered the rest of the driveway with an integrally
colored topping, feathering it up against the flagstones.
Any slop that got onto the flagstone washed nght off,
thanks to the sealer.
. After a day he washed
the entire driveway with muriatic acid, which brought
up the sand grit for a more natural
feel. "It looked awesome," Ralston says.
The finished driveway was featured in Sunset Magazine.
Victor Pachade of Colormaker Floors in Vancouver, Canada,
tells of a faux flagstone pattern that Colormaker created
while staining a cracked floor at a cancer care Center
in Yakima, Wash. -Me Cracks Were filled with anchoring
cement, then sprayed with muriatic acid.
Muriatic acid was also sprayed in a few other meandering
lines across the floor to delineate a pattern of enormous
flagstones. Then the entire floor was stained.
"The areas that were sprayed with the muriatic
acid did not react to the acid stain, so there wasn't
any acid stain color there," Pachade says. "That
formed a border or a grout line for the flagstone."
Sometimes contractors opt to emphasize good-looking
cracks.
"A crack is like a living thing," says Mark
Donaldson, owner of Skookum Floors in Seattle. "It
occurs and it kind of does its own thing and moves in
its own direction. Most of the time it could be interpreted
as something ies not."
Donaldson sometimes transforms cracks into crawling
vines by chasing them and filling them with colored grout.
To complete the effect he might put flowery splashes
of color at the ends of the cracks.
For interesting color
effects, Donaldson likes to fill a crack with acid
stain and then blast the crack with
compressed air. "The color kind of explodes from
the crack," he says.
One idea Donaldson
would like to try is to embed rope lighting (that flexible
plastic tube lighting) into some
cracks with a clear epoxy. "four cracks would have
a glow in them," he says. "I've never done
it before, but I always thought that would be cool."
Of course, another way to go is to simply let cracks
be cracks. Cracks can add character to a floor, especially
a stained floor, notes Ron Cottingham, decorative concrete
program manager for Dayton Superior.
"The idea with stains is to make a floor look timeworn
and paitned," he says. "When stain gets down
in a crack, it darkens along the edges and makes the
crack more visual, so it become part of your design."
And why not show off
a genuine concrete crack? After all, some clients pay
good money for fake ones, Cottinghain
points out. "In the stamping business, we manufacture
stone or slate textured skins that have cracks in them,
where we make the new concrete look like it has cracks!" he
says. |
