Evening star., 1949-06-13
Treating Concrete Floors

Editors note-FollotDino the
appearance of a number OF let
ters In the Readers Clearing
House discussing methods Of
treating concrete floors tohich
haze a tendency to dust" or
:~kSt,s the Portland Cement AS
soctdtton has oiUer US permits
sion to reprint part OF an article
put out By 1t on Just this sub
ject. As the information pre-
sented is authoritative and
practical, toe felt 1t would be of
interest to nlany readersJ
It liz essential that the floor be
clean and free from plaster. oil.
paint or other foreign substances
before giving any further treat
ment. It should be fairly dry to
assist penetration. When paint Of
any kind Is to be used 1t is i'm
portant that the concrete be abso-
lutely dry and properly prepared
to receive the paint.
FIuosilicote Treatment
The duosilicates OF zinc and
magnesium, when dissolved in
water, have been used with good
success. Either Of the fluosilicates
may be used separately, but a
mixture of 20 per cent zinc and 80
per cent magnesium appears to
give the best results. In making
up the solutions. " pound of the
fuosilicate should be dissolved in
/ gallon water for the first applica-
ton and pounds to each gallon
for subsequent applications. The
solution may be mopped on or
applied with sprinkling can and
then spread evenly with mops.
Two or more applications should
be given, allowing the surface to
dry between applications. About
3 or 4 hours are generally required
for absorption. reaction and dry
ing. Care should be taken to mop
the floor with water shortly after
the last application has dried to
remove incrusted salts, otherwise
white stains may be formed.
Sodium SiIicate Treatment
Commercial solution is about a
40 per cent solution. 1t is viscous
and requires thinning with water
before it will penetrate concrete.
A good solution consists Of 3 gal
Ions water to each gallon Of sill
cate. Two or three coats should
be used, allowing each coat to dry
thoroughly before the next one is
applied. Scrubbing each coat with
stiff fiber brushes or scrubbing
machines and water will assist
penetration of the succeeding ap-
plication.
Aluminium SuIphote Treatment
This treatment consists Of one
or more applications Of solutions
of aluminium sulphate. The solu-
ton is made in a wooden barrel or
stoneware vessel and the water
should be acidulated with not more
than. / teaspoon of commercial
sulphuric acid for each gallon of
water. The sulphate does not
readily dissolve and requires oc-
casional stirring for a few days
until the solution is complete.
About 21z pounds Of the powdered
sulphate will be required for each
gallon of water. For the first
treatment the solution may be di-
luted with. twice its volume of
water. Twenty-four hours after
this application the stronger So
luton may be used. and "a hours
should elapse between subsequent
applications.
Zinc SuIphote Treatment
This treatment consists in the
application Of a solution contain
ing 11a pounds zinc sulphate anS
O teaspoon Of commercial sui
phuric acid to each gallon of
water. The mixture is applied in
2 coats. the second coat applied
4 hours after the first. The sur
face should be scrubbed with hot
water and mopped dry Just before
the application of the second coat.
This treatment gives the floor
a darker appearance.
Oil Treatment
Linseed, china wood and soy
bean oils are used as floor treat
ments. Boiled linseed oil dries
faster than the raw oil. It is not
necessary to build up a heavy sur
face coating as penetration Of the
oil into the surface is desired
The oil should be diluted with
turpentine or other suitable thin
ner, up to so per cent thinner for
the first coat and less for subse-
quent coats. Heating the oil to
$50 degrees or so and application
to warm floors are also helpful In
securing better penetration. Two
or three coats may be applied
with mops or brushes and the
excess removed with q squeegee
before the oil gets tacky. These
treatments tend to darken the
floor somewhat.
Coveroge
The amounts of the above solu-
tions required to treat floors will
vary considerably with the poros-
ity of the concrete. Generally, a
gallon of any one of the solutions