“Brick from the run of the kiln” will answer for most houses; those of
even color, well-burnt and regular shape, should be selected for the
outside walls and chimneys. Those of irregular shape, too hard or too
soft for outside walls, can be used for filling in, or partition walls.
No soft burnt brick should be allowed where exposed to the weather.
Supposing the foundation is finished, and first-floor joists are laid,
commence by filling between joists, flush with the top of joists and even
with the inside of foundation walls, so no shelves are left between the
joists for the purpose shown in hints under the head of “Foundation,”
page 6.
If the inside of outside walls are to be furred, be prepared to insert
strips about the thickness of common lath between brick joints at points
where base boards are to be put, and to fasten long strips or grounds as
called by plasterers. No mortar should be put between the lath strip and
the brick, but let the lath be pressed by the surface of the upper and
lower brick; the natural settling of the wall will hold the lath tight
enough to bear any amount of nailing.
For doors and windows, insert pieces same thickness, but large enough to
receive the casings. These thin pieces inserted in the mortar joints are
better and cheaper than plugs or wooden brick, which are apt to shrink
and become loose when the brick-work dries. It is very important that
flues for ventilation and chimneys be properly started (see “Chimneys”)
and carried through the roof to a height, if possible, above the apex
of the roof. Ventilating flues should run alongside the chimney flues
where the construction favors them. Too much care cannot be taken in
building these flues. They should be carefully and smoothly plastered on
the inside, and no wood-work be allowed nearer than five inches from the
inside of flue. It is customary to use headers (cross bricks) every five
courses, to bind the walls together. Many people object to headers, and
prefer to expose only the edge surface of the brick. This can be done by
clipping the inside courses of outside brick so as to allow the middle
course to lay angular across the wall, with opposite courses resting half
way between and on the outside courses, or by using square brick. The
latter is a saving of labor if they can be had at a reasonable price.
The thickness of walls depends entirely upon the size of structure to be
built. For ordinary dwelling-houses, twelve inches is thick enough for
outside walls and nine inches for partition walls. Mortar for brick-work
above foundation should be made of one part of good lime, slacked at
time of mixing the mortar, and four parts of screened sharp sand. The
cementing qualities of sand and fresh lime depend on the purity of the
sand. By pure sand we mean that which is free from loam or clay.