Evening star., 1942-08-15
Painting Brick Houses
White Is More Than
Justa Vogue
Coating Keeps Home
Cooler in Summer,
Saves Winter Fuel

Saves Winter Fuel
The vogue for painting brick
houses white. which has become
evident throughout the country in
recent years, especially In the
modern developments, while highly
attractive In itself, is much more
than a mere matter of decoration.
1t is conservation measure which
Is fitting at any time, but especially
50 In wartime. when measures to
increase Inability and possible fuel
saving In existing structures should
be factors in the national economy.
It has long been demonstrated
that dark -colored surface exposed
to sunlight gets very much hotter
than white or light-colored sur
face-so much so that it has long
been a classic experiment to fry"
eggs on black pavement on very hot
summer days, but 1t remained for
the scientific section of the National
Paint, Varnish and Lacquer As
sociation here to make deliberate
study of the effect of heat on the
different colored houses and def
nitely determine that paint is
highly important insulator.
Two identical penthouses were
built on the roof of the associa-
tion's laboratory. They were placed
upon ventilated foundations con-
sisting of two courses of brick
capped with copper flashing to
prevent water seeping up into the
walls proper. The walls, them
selves. were built four inches thick
"a single course of brick, with
standard mortar joints.
Standard Construction.
The inside walls above the floor
line were plastered and finished
with smooth white coat. For the
floors, standard construction was
followed with the use of sub-foor
ing with tongue and groove top
foors.
The roof was pyramidal and
covered with sheet metal painted
red. Between the roof and the CELL
ing, four inches of commercial in
sulation was installed. In the north
wall to facilitate changing of chart
on the recording instrument and to
provide limited amount of ventila-
ton. was window three feet by
three feet.
The houses were equipped with
combined recording thermometers
and hair hydrometers which pre-
Viously had been standardized in a
constant temperature room. When
installed, both instruments were
accurate to within / degree Fahren-
heit and per cent relative humidity
at go per cent. One of the houses
was painted white and the other
left umpainted. Otherwise, they
we're identical.
Tests, with careful recordings,
were continued during the summer,
and from instrument records a
graph was prepared showing the
typical temperature differences be-
tween the house painted white and
the unpainted house, covering a
period of one month.
Painted House Cooler.
The painted houses was demon
strated to be at least IA degrees
cooler.
The chart from the painted house
showed a constant relative humidity
In the test room. indicating little
or no influence of moisture con-
Quoted through the walls, whereas
the unpainted house chart showed
a variation of about Is per cent
relative humidity.
The National Bureau of Stand
ards in a comparative test of daily
mean rise in temperature OF test
panels of different colors exposed
to the sun reported a range from
80 degrees Fahrenheit for the
glossy white paint to 20.e degrees
for black paint-a difference of IL
degrees. It was found that some
unpainted roofing materials were
heated almost as hot as the black
panel, and in the case OF one red
roofing material, 2l5 degrees or 6
per cent hotter. Flat white paint
was a close second to glossy white
in coolness, the difference between
the two types of white being only
4 degree Fahrenheit. Ivory paint
showed a rise of 1o.2 degrees, canary
yellow, 10.9 degrees; pearl gray, 1873
degrees. silver gray, 1879 degrees;
light lead colored paint, Isl de-
grees; slate colored paint, 1853 de-
grees, and medium green trim
color, 2o4 degrees, or almost as
much as black.
The same paint which acts as an
insulator for the wall in summer
also helps to keep the house warmer
in winter by sealing the outside
surface against moisture and keep
ing it from penetrating through the
walls. Water is many times as
rapid a conductor of heat or cold
as air. which fact indicates the
economy and advantage of a dry
wall as compared with water
soaked one in both summer and