T-SHAPED:
A traditional foundation
method to support a structure in an area where the ground freezes. A footing is
placed below the frost line and then the walls are added on top. The footing is
wider than the wall, providing extra support at the base of the foundation. A
T-shaped foundation is placed and allowed to cure; second, the walls are
constructed; and finally, the slab is poured between the walls.
In summary:
| T-shaped foundations are used in areas where the
ground freezes. | |
| First, the footing is placed
| |
| Second, the walls are constructed and poured
| |
| Lastly, the slab is placed.
|
PICTURE OF THE T-SHAPED FOUNDATION AT THE END OF THE PAGE.
Slab-on-grade
foundation:
As the name suggests, a slab
is a single layer of concrete, several inches thick. The slab is poured thicker
at the edges, to form an integral footing; reinforcing rods strengthen the
thickened edge. The slab normally rests on a bed of crushed gravel to improve
drainage. Casting a wire mesh in the concrete reduces the chance of cracking. A
slab on grade is suitable in areas where the ground doesn’t freeze, but it can
also be adapted with insulation to prevent it from being affected by the frost
heaves. (See below)
In summary:
| Slab on grade used in areas where ground does not
freeze. | |
| The edges of the slab-on-grade are thicker than
the interior of the slab. | |
| The slab-on-grade is monolithic (poured all at
one time). |
PICTURE OF SLAB ON THE GRADE FONDATION FOUNDATION AT THE END OF THE PAGE.
Frost
Protected:
In summary:
| Only works with a heated structure.
| |
| Has the benefits of a the slab-on-grade method
(concrete poured monolithically) in areas subject to frost.
|
T-SHAPED
Slab-on-grade
foundation:
Frost
Protected