Stucco News

Questions and answers on Stucco and Plastering-- November, 2014


Reston, Virginia- The RAW TRUTH about the stucco.

The finish coat material on houses in Reston built in the 1970's was Ken-o-tex, A spray on material much like the acoustic spray used on drywall ceilings. Ken-o-tex was a thick paint, with vermiculite or styrofoam used for the aggregate, or texture.

Kenotex was sprayed on cement basecoats, and even directly on plywood.

I worked in Reston in 1973, which is how I got my information.

On plywood applications, the joints were taped and the tape and nails were coated drywall style with a sticky material that was referred to as hard-coat at the time. From what I heard, this hard coat was real expensive, and cost about 50 dollars a gallon back in 1973. This material was made from casein, which is a milk by-product. Hard coat disappeared from the market after the 1974 energy crisis, which drove the cost of casein up.
Mystic secret revealed !
We patch the peeling kenotex with my own formula made from white portland cement, Number 3 Q-ROK, a coarse silica sand, and plenty of acrylic. You might say we are making our own paint. I hope our mix lasts longer than the Kenotex.

I can patch the kenotex if it was applied over a cement basecoat. I doubt this mix will bond to plywood. If I had to patch kenotex on plywood, I would need to put on metal lath and stucco the whole wall.

I don't think they have made Kenotex in 40 years.

The sales person for Kenotex in Reston was "The Kenotex girl", who traveled around Reston in a big black luxury car, and wore a tight, very short leather skirt.

LEADING CAUSES FOR FAILURE:
Deteriorated metal corner bead used in
                          stucco
PLEASE READ THIS !
These metal corner beads are made for interior plaster. They will fail over time if used outside. I don't care what your specs say they should never be used outside.
Inadequate coping deteriorates blocks in
                          Reston, Virginia   INADEQUATE COPING DETERIORATES BLOCKS.
This stucco is less than 40 years old and is already
falling apart due to deteriorated corner beads and
inadequate coping (the three side fashing at the
top of the wall is called coping).
Another townhouse less than 40 years old has stucco
failure and even badly deteriored blocks due to bad
and missing coping.
Stucco is out past the
                          coping
New coping and new
                          stucco in Reston, VA
The coping is easy to correct. One would
just need to cut the rivets holding the front flange in
place, pull it out where it protrudes well past the wall,
and put in screws.
Here we are putting on a new coping.
This wall never had any coping, leading to it's failure.


                    My secret formula for patching stucco in Reston is revealed.


secret formula for
                          patching stucco in Reston
Spraying stucco finish
                          in Reston, Virginia
White portland cement, Number 3 Q-ROK, a coarse silica sand, and plenty of acrylic is sprayed on with a hopper gun.
We did the whole back of a townhouse this way
over a basecoat. If you spray directly over
the Ken-o-tex, the wall can peel and fail because
you are just putting good on top of bad.
Patches are rubbed down
                          using a rubber float.
Patches are done by hand rubbing the mortar down
with a rubber float. This way doesn't look bad.

Spraying mortar slops mortar all over the place, so
the hand method is more practical for little patches.

It taks a long time to cover and tape off and it isn't worth
the trouble for small areas