Chapter 6  Building Layout
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undisturbed during the construction of the
building project. A stake driven at one corner
of the lot or building site, or even a mark chis-
eled into concrete curbing, often serves as the
benchmark.
Checking grade
Building sites are rarely perfectly level. All have
high and low points. These highs and lows need to
be determined before the height of the foundation
is established. This job is easier when the site is
fairly level, as in Figure 6-17.
1. Locate the instrument midway into the site,
then level the instrument.
2. Take a line-of-sight reading on a rod held at
one edge of the site.
3. From the position of the target on the rod,
note the elevation (5′-2″ in Figure 6-17) and
record it. Surveyors keep a notebook for such
recording, since many people may need to
refer to the readings. Carpenters generally jot
readings on a piece of scrap lumber. Usually,
they are the only ones needing to refer to the
readings.
4. Rotate the telescope 180°. Take a line-of-sight
reading on the rod located at the opposite side
of the site.
5. Note the elevation at the target position on the
rod (5′-9″ in Figure 6-17). Record it as before.
6. Subtract the lower elevation from the higher
one to find the difference (7″). This number is
the actual vertical increase or decrease from
one known point to another.
When setting grade stakes for a footing or
erecting batter boards, set the instrument in a central
location on the site, as shown in Figure 6-18. The
distances to the target (or rod) will be roughly equal.
This will improve the accuracy of the readings taken
for each corner. An elevation established at one
corner can be quickly transferred to other corners
or points in between.
6.5.4 Setting Footing Stakes
Grade stakes for footings are usually first set
to the approximate level “by eye.” They are then
carefully checked with the rod and level as they
are driven deeper. The top of each stake should
be driven to the required elevation.
Sometimes, reference lines are marked on
construction members, stakes, or other objects
near the work. The carpenter then transfers
them to the formwork with a carpenter’s level
and rule as needed. This eliminates the need to
repeatedly establish the same elevation.
There may be situations where the existing
grade will not permit the setting of a stake or
reference mark at the actual level of the grade. In
such cases, a mark is made on the stake with the
information on how much fill to add or remove.
The letters C and F, standing for cut and fill, are
generally used. See Figure 6-19 for an example
of how stakes are marked.
Pier
footing
Building line
Tripod
Figure 6-18. A central location for the instrument will
make finding and setting grade stakes easier and more
accurate.
Cut:  The process of removing material to achieve the
desired grade.
Fill:  The process of adding material to achieve the
desired grade.