_CONSTRUCTION OF HOUSES AND BARNS WITH REFERENCE TO HEALTHFULNESS_
Any liability to disease that may come from faulty construction of
habitations is likely to spring from a polluted subsoil. Such pollution
vitiates the air drawn from that soil and is a source of danger on
account of the resulting impurity of the whole atmosphere within the
house.
_Shutting out soil air._
We have already seen (Chapter II) how it is possible for soil charged
with organic matter to deliver, either through suction from a heated
house or on account of a rising ground water, soil air into the cellar,
and also that moist air may enter the house in the same way. In order to
prevent this, it is plainly necessary to interpose some air-tight or
water-tight layer between the house and the soil, and also, since
perfection in this layer is impossible, to make provision for draining
away any water which may accumulate against the walls. Ordinary builders
do not lay much emphasis on the importance of either of these
precautions, and while one may often see cellar walls roughly and
carelessly coated on the outside, with tar or asphalt, a thoroughly
water-tight coating is not a common practice. Similarly, while
draintile are often laid around a house, they are either laid so near
the surface as to be useless or else they have no porous filling.
[Illustration: FIG. 5.--Exterior wall-drains.]
To prevent moisture from entering the cellar, the first provision should
be a tile drain (not less than four inches in diameter) laid completely
around the house (see Fig. 5) on a grade of not less than six inches in
one hundred feet. This drain at its highest point ought to be one foot
below the bottom of the concrete floor of the cellar, and more than
this, of course, at the lower end. This should be laid before or at the
time the foundations for the house are being built, although it is
possible to dig the necessary trenches and lay the tile after the house
is built. If the available grade is small, this drain may be laid in two
lines directly under the cellar floor as shown in Fig. 6. At the points
_A_ the bottom of the tile should be at least a foot below the dirt on
which the cellar floor will be laid, and at the point _B_, about two
feet. This drainpipe is best laid with regular sewer pipe and without
cement in the joints. Then coarse gravel should be filled in around this
tile so as to allow water to enter the pipe without carrying soil that
later might settle in the pipe.
[Illustration: FIG. 6.--Interior cellar-drains.]
_Position of outfall._
There is always a question of where this drain shall end and into what
it shall discharge, for in some soils this drainpipe may discharge
continually. To allow the drain to empty on the ground means that its
outer end will be broken; that if discharge takes place just before
freezing weather, the drain will fill with ice and be broken, so that
some other method must be devised. If the outer end can be laid into a
brook where the velocity prevents the water from freezing, or where the
outer end can be kept below water, a satisfactory disposal is found.
Otherwise, it is better to discharge into a small covered cesspool,
provided the soil is sufficiently porous to take care of the water, and
provided the level of the ground water allows the construction of such a
cesspool. In any case, it should be at some distance from the house, so
that if it overflows, the water will not seep back to the cellar walls.
By water-proofing the main wall and then backfilling against the wall
with coarse gravel or broken stone, the same results as with open
areaways are obtained and at a much smaller cost.
_Dampness of masonry walls._
One fact peculiar to all kinds of masonry and known to all careful
observers is that stone work, brick work, and concrete will allow
dampness to permeate, whether it comes from water-bearing soil or a
driving rain. One objection to concrete-block houses has been that a
hard rain would cause moisture to form on the inside. Brick buildings
have the same defect when the walls are built solid.
An air-space in the cellar walls is the only way of insuring a dry
cellar, if the bottom of the cellar is below the level of the ground
water. A four-inch course of hollow brick may be used on the inside, or
the wall may be actually divided into two walls with a space between.
[Illustration: FIG. 7.--Wall modes of making air-space.]
Figure 7 (after Warth) shows three different ways by which an air-space
is secured and the two component parts of the wall held together. In the
top view, the two walls, one eight-inch and one four-inch, are held
together by wire ties, leaving an air-space of about four inches. In the
middle drawing the walls are tied together by making the air-space three
inches wide and then lapping the brick laid as headers over both walls.
In the bottom view special terra-cotta blocks are used which pass
through both walls. There can be no question of the value of such
construction in eliminating dampness from the inside wall, but, it must
be admitted, the cost of the walls is increased somewhat.
_Use of tar or asphalt on the wall._
Instead of an open space, nowadays, it is more customary to thoroughly
plaster the outside of the cellar wall, and then paint it with a tar
paint put on hot, which will adhere fairly well to the cement or
masonry. Asphalt cannot be very readily used for this purpose unless it
is an asphalt oil with but little bitumen paste. A paving asphalt, for
example, even applied hot, does not adhere to the masonry, but slides
down the walls as fast as it is applied. A successful method, however,
of using such asphalt is to build the cellar wall in two parts,
separated about half an inch, and filling in the intervening space with
liquid asphalt. In this way, the asphalt is held in position, and is an
absolute prevention of dampness.
Another method used successfully in the construction of one of the large
railroad stations in Boston consists in painting the outside of the wall
with tar and then pressing into the hot tar several layers of tar paper,
the separate sheets overlapping in a special coating of tar. These
sheets are thus made continuous around the building and under the
basement so that no water can enter the building.
[Illustration: FIG. 8.--Water-tight wall.]
A cross-section of one of the depressed tracks entering the Boston
Station is shown in Fig. 8. The heavy black line represents ten
thicknesses of tar paper, each one thoroughly painted with a thick paint
of hot tar. It should be noticed that this water-tight coating is
inclosed between masonry walls, so that the coating cannot be injured.
It is possible theoretically by these methods to build an underground
cellar so truly water-tight that it could be set down in a lake, where
it might float like a boat and not leak a drop, and there may be some
locations that require such construction, such as a low river valley or
an old salt marsh or a city flat, where no adequate drainage is
provided. But practically such construction will always be found
expensive, and is, in most cases, unnecessary and ineffective, as
already indicated, and where the percolating water cannot be tolerated,
involves the installation of some kind of pump to throw out the water
that will inevitably, in larger or small quantities, pass through the
best water-proofing. It is, therefore, the part of wisdom to place
reliance on draining the water away from the house rather than on
water-proofing the cellar wall.
_Dry masonry for cellar walls._
It may not be out of place to add a word of caution against the practice
of building cellar walls of loose stone, without mortar. They make no
pretense of being water-tight, they offer no resistance to the entrance
of rats, and they soon yield to the pressure of the earth and present
that wobbly, uncertain appearance of cellar walls seen in rural
districts. Nor should the idea that the interior is to be visible and
the exterior invisible blind the builder to the fact that it is far more
important to have the outside smooth. If smooth, there are no projecting
surfaces for water to collect in, no edges for the frozen earth to cling
to and by expansion tear off from the wall. If smooth, the joints in the
masonry can be pointed or filled with mortar, and thus a suitable
surface for the tar or asphalt is provided.
[Illustration: FIG. 9.--Rough-backed wall.]
In Fig. 9 (after Brown) is shown a cellar wall with rough, irregular
back, and it is easy to see how water would readily find its way down to
one of the projecting stones and then along such a stone, through the
wall into the cellar. With such a wall the action of the frost is more
severe than with a wall with a smooth back, so that the wall in Fig. 9
is gradually pulled apart by alternate freezings and thawings. Figure 10
(after Brown), on the other hand, shows the cellar wall as it should be
with smooth, even exterior, along which the water passes easily, with
gravel backing, through which the water escapes to the drainpipe.
[Illustration: FIG. 10.--Even-backed wall.]
_Damp courses in walls._
[Illustration: FIG. 11.--Four modes of making water-proof cellar walls.]
Another important means of keeping moisture from the cellar walls is to
provide what is called a damp course at about a level with the top of
the cellar floor. Where the soil is naturally damp, and where the cellar
wells are not adequately water-proof, a second damp course should be
provided at the level of the ground so that moisture from the damp
cellar walls may not pass up into the above ground portion, which is
naturally dry. These damp courses, in their simplest form, consist in
bringing the masonry level around the building, and painting the top
surface with liquid coal tar.
[Illustration: FIG. 12.--Waterproofing of cellar walls.]
Another method is to paint the masonry with liquid asphalt, and then
imbed in this paint a thickness of asphalt-covered building paper which
is again painted with asphalt. This may be done in the horizontal layer
where it could not conveniently be done vertically.
Four different ways used in France for securing dry cellar walls are
shown in Fig. 11. The heavy black line represents the damp course,
which, when added to the effect of the interwall space, which is shown
in all the drawings but the first, and there replaced by a deep drain,
insures absolute freedom from all moisture within the cellar. Figure 12
shows sections recommended by Dr. George M. Price, and indicates clearly
the location of the damp course.
_The cellar floor._
The floor of the cellar, in the same way, must be kept from dampness,
and this is best done by covering the cellar floor with a layer of
concrete, one part cement, three parts sand, and six parts broken stone;
or, one part cement and eight parts gravel may be used. Care should be
taken, however, that the gravel does not contain an excess of sand, and
it is always well in using gravel for concrete to check the proportion
of these two materials. This may be done as follows: Sift the gravel
through an ash sieve so that it is free from sand; fill a ten-quart pail
even full with the gravel and then pour in water to the top of the pail,
keeping account of the amount of water poured in. This volume of water
gives the proper amount of sand to use with the gravel for concrete, and
if more sand than this was present in the original gravel, it should be
sifted out until the proper proportion is reached.
Concrete is not water-tight, and the concrete floor of the cellar must
be treated in some way to prevent water or moisture rising through this
floor. One method is to cover the concrete thus laid with a denser
mixture of cement and sand, put on three fourths of an inch thick, and
made by mixing equal parts of sand and cement; or the asphalt layer
already referred to in the cellar walls may be carried across the
cellar, putting, as before, a paint layer on the concrete, then paper,
then another paint layer, making it continuous and without a break from
outside to outside. On top of this, to prevent wear and tear, a floor of
brick, laid flat, or a two-inch layer of concrete may be laid.
_Cellar ventilation._
The great importance of the cellar as that part of the house where, if
anywhere, unhealthy conditions exist, justifies this prolonged
discussion, and before leaving the subject, ventilation in the cellar
should receive a word of encouragement. Too many cellars are damper than
need be, are musty and close, full of odors of decaying vegetables and
rotting wood, entirely from lack of ventilation. The cellar windows are
small and always, closed. The cellar door is seldom opened, and never
with the idea of admitting air. The impression on entering such a cellar
is of a tomb.
The cellar, even in that part devoted to storing vegetables, needs
ventilation as much as the house does, for the cellar air finds its way
up into the house, and an unventilated cellar means a house with air
deficient in oxygen and overloaded with carbonic acid, a condition which
causes pale faces and anaemic bodies. Far better and healthier is it to
open all the cellar windows, covering them with coarse netting to keep
out animals and with fine netting to keep out insects, and let the
disease-killing oxygen and sunlight in. Malaria comes from the cellar,
whenever the malarial mosquito can find there a breeding place. The
writer has seen many cellars in which mosquitoes were living the year
through in entire comfort, utilizing the moisture and warmth of the
cellar to enjoy the winter months and up and ready for their mission at
the first sign of spring. A cistern in the cellar is objectionable on
this account, and if one exists, it should be covered with mosquito
netting.
_The old-fashioned privy._
Another source of ill-health as well as of temporary discomfort is the
typical construction and continued use of an outside closet or privy.
The physical shrinking from the use of the ordinary building is most
reasonable. As generally constructed, great draughts of air (presumably
for ventilation) are continually passing through the small building, and
when the temperature of the outside air is at zero, or thereabouts, only
the strongest physique can withstand the exposure involved without
serious danger of consumption, influenza, and pneumonia, or at least
inviting those diseases by reducing the vitality of the body. Two
improvements suggest themselves and should be put into effect wherever
this primitive construction must continue to be used.
In the first place, the building itself should not be fifty or a hundred
feet away from the house, so that every one is exposed to rain, snow,
slush, and ice in making the journey thither. But some corner of the
woodshed or barn should be utilized or the small building should be
moved up by the back door and connected therewith by a roofed passage.
The barn location is objectionable if it involves outdoor exposure in
going from the house to the barn. A liberal use of earth in the privy
vault will eliminate odors, and a water-tight box or bucket makes a
frequent removal of the night soil practicable.
In the second place, a small stove ought to be provided to warm the
closet in the coldest weather. Then the dislike to suffer from the cold,
which leads so many to postpone nature's call, will be avoided, and the
consequent digestive disorders which come from constipation and
intestinal fermentations prevented.
_Cow stables._
In matters of health, aside from ventilation, which is discussed in the
next chapter, there is little to be said concerning the other buildings
on the farm. Barns for hay are not involved. A few words may profitably
be devoted to barns for stock, involving, as they do, by their
construction, the health of the stock. One enthusiastic farmer writes
that it is possible for farmers to keep their stock at all times under
conditions which are an improvement upon the month of June. He believes
that the cow stable should be as comfortable for the cows as the house
is for the owner, subject to no fluctuations of temperature, and that,
in this way, the health as well as the comfort and milk production of
the cows would be maintained.
Light should be listed as the first essential of healthy stables, light
to kill disease-producing bacteria, to make dirty corners and holes
impossible, and to react on the vitality of the animals. Compare this
with some stables where fifteen, twenty, or thirty head are stabled in
an underground dugout with two or three small windows not giving more
than four square feet in all. Stable windows should be set, like house
windows, in two sashes and capable of being raised or lowered at will.
In winter a large sash may be screwed over the regular window to keep
out frost and moisture, provided there is some independent method of
ventilation.
For good healthy conditions, a cow needs about 500 cubic feet of space,
with active ventilation. In old stables, with poor construction, as
little as 200 cubic feet per cow was allowed, and when stables were made
tight with matched boards and building paper, 200 cubic feet was found
to be too small, and it was recommended that one cubic foot be allowed
for each pound of cow. But when tried by wealthy amateurs, it was found
that this was too large; the stables were damp and cold in winter and
became a predisposing factor in the development of tuberculosis. Between
the two extremes, 200 and 1000, is the practical average named above,
namely, 500 cubic feet of air space for each cow.
For the health of the cow as well as for the good quality of the milk
the stable should be built with special reference to being kept clean.
The ceiling should be dust-tight, so that if hay is stored above, it
will not sift through. The part of the barn where the cows are kept
should be separated from the rest of the barn by tight partitions and a
door into the cow stable. Nothing dusty or dirty should accumulate. The
floor of all stables for cows, horses, hens, and pigs should be of
concrete to insure the most sanitary construction. Planks absorb
liquids and wear out rapidly under the feet of the stock. Concrete can
be kept clean, is nonabsorptive, and if covered with some non-conducting
material, like sawdust, shavings, or straw, is a perfectly comfortable
floor for the animals.
_Use of concrete._
No development of recent times has tended more toward the improvement
and greater comfort of house building than the use of concrete. In the
earlier houses, the cellar walls were so badly built and the connection
between the top of the cellar wall and the timber sill of the house was
so poor that the winter's wind blew through above to the manifest
discomfort of those in the house. The writer remembers sitting in the
best room of a well-to-do farmer, and watching, with great interest, the
carpet rise and fall with the gusts of wind outside. To avoid such
unhappy consequences, farmers have been accustomed to bank up the house
outdoors in the fall with dry leaves, spruce-boughs, or manure, usually
to a point on the woodwork. This, of course, closes the cellar windows
for the winter for the sake of keeping out the wind. A concrete wall, at
the present price of cement, using gravel for the mixture instead of
stone, need cost but little more than the price of the cement and the
labor involved, and a tight cellar wall may thereby be obtained.
If the soil in which the cellar is dug is firm enough, the outside of
the excavation can be made so that no form on that side will be
required, but it is always better to make the excavation about two feet
more than necessary, to put forms inside and outside, and, after their
removal, plaster or wash the wall with a thick cream of cement and
water. In carrying the wall above the ground, forms must be used with
great care to secure a smooth surface, and Fig. 13 shows two methods
suggested by the Atlas Cement Company.
[Illustration: Fig. 13.--Cellar-wall forms.]
There are so many forms of construction where concrete is not merely a
convenience but a great advantage in the matter of health around the
house, and particularly a house in the country, that there would be no
end if one once began enumerating and describing the various methods and
processes involved. Besides the cellar walls and cellar floor, there are
outside the house, silos, manure bins, walks, curbing, steps,
horse-blocks, hitching and other posts, watering troughs, and drainpipe,
all successfully made of this useful material. In the barn, the barn
floor, the gutters, the manger and watering troughs, cooling tanks, and
sinks are also made of cement. While it is possible to differentiate
between the methods and the mixtures for these various purposes, it will
not be greatly in error if the construction always follows the following
principle.
Use enough cement to fill the voids in the gravel or in the sand and
stone mixture employed, and have enough sand in the gravel or with the
stone to fill the voids in the stone. This is readily determined, as
already suggested, by the use of water. The water, which will occupy the
voids in the stone, represents the necessary sand. When this amount of
sand and stone is well mixed, the water then permeating the interstices
represents the necessary cement, though it is a good plan to add about
10 per cent extra to allow for imperfect mixtures.
The mixing should always be done so thoroughly that when put together
dry, no variation can be seen in the color of the mixture. It is
surprising to see how readily a streak of unmixed dirt or of unmixed
cement can be detected in a pile by the difference in the color which it
presents. Such mixtures should always be made dry first and then the
water added and again mixed until the result is of a perfectly firm
consistency. Such a mixture can be applied to any of the purposes
mentioned, and, in general, it is better to have too much water than not
enough. The only difficulty with a very wet mixture is that the forms
require to be made nearly water-tight, whereas with dry mixtures the
same attention to the forms is not necessary.
If the concrete is to be used in thin layers, as in pipe or watering
trough, where a smooth surface is wanted, better results are usually
obtained by using a dry mixture and fine gravel and tamping the mixture
with unusual thoroughness. It is always unsafe to smooth up or
re-surface a piece of concrete. The difference in texture of the surface
coat causes it to expand and contract differently from the mass of
concrete underneath, and inevitably a separation occurs. If it is
desired to put on a sidewalk, for instance, a smooth top coat, the
consistency of the two kinds of concrete should be alike, and the top
coat should be applied almost immediately after the bottom layer is put
in place. Where concrete is used to hold water, a coat of neat cement
should always be put on with a broom or a whitewash brush, mixing the
neat cement with water in a pail, and it does no harm to go over the
surface three or four times, the object being to thoroughly close the
pores in the concrete.
For floors of cellars or barns, the dirt should be evened off and tamped
and then the cement concrete should be spread evenly over it, and tamped
just enough to bring the water to the surface. When partially dry, a
better finish is obtained by lightly troweling the concrete. In a cellar
or barn, it is not necessary to divide up the area into squares or
blocks as is done with sidewalk work, but the entire area may be laid in
one piece. In order to keep the surface level, however, it may be found
convenient to lay down pieces of 2" x 4" scantling, the tops of which
shall be on the desired level of the finished floor. By filling in
behind these scantlings, which can be moved ahead as the filling
progresses, the exact level desired can be obtained. Usually four inches
thick will be a proper depth of concrete for this purpose.