A 2-ft. level works just fine on small projects like installing small sections
of wall tile, building closet walls and installing single cabinets. But
when you have to quickly and accurately set elevations over long distances
for bigger jobs like building decks, digging trenches and setting concrete
form boards, this trusty ol' level is out of its league. Any time you try to
pencil a long level line by repositioning that 2-ft., or even 4-ft., level end to
end, you'll build in an error that magnifies as you extend the line.
There are several tools you can use indoors and out for improving your
leveling results. We'll show you the best techniques and tools for short-,
medium- and long-distance leveling.
Two levels for short distances (4 - 15 ft.)
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Photo 1: Extend the level
Mark exact elevations for mounting deck beams using a 2-ft. level atop a
straight 2x4. Find the straightest 2x4 by sighting down the edges. Pencil the
height of the wall ledger onto each deck post.
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Photo 2: Leveling trenches
from a level string line. Tap in a
reference stake and then a series
of measuring stakes 6 ft. apart
along the trench. Check the trench depth
for the proper drainage
slope by tying off the
string line level at each
stake and measuring
the depth of that spot
in the trench.
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Photo 3: Line level
Measure off the
string line once the level reads
true and stabilizes. The
line level is true when
the bubble settles
between the hairlines.
Combining a straight board and
a 2-ft. level is a good yet inexpensive
way to level over shorter distances.
For tasks like laying out
deck beam heights (Photo 1), set
your level on top of a perfectly
straight 2x4 to accurately extend
its reach. Two-by-six and 2x8 lumber
is too heavy to hold steady. To
make a lot of measurements
quickly, strap the level to the 2x4
with duct tape or an elastic cord.
For jobs where absolute accuracy
isn't essential, like digging
slopes in trenches, use an inexpensive line
level (Photo 2). Hook it directly
onto a strong string, like nylon
mason's line. For the level to work
properly, use only one line level
per string, draw the line very tight
and make sure there's little wind
to blow the level around.
Electronic water levels work well at medium distances (15 - 50 ft.)
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Photo 4: First calibrate
Calibrate an electronic water level by first attaching it plumb and
level to a plywood scrap. Fill the tube with water and bleed air out of
the line. Calibrate by loosening both tube clamps, turning on the electronic
level and raising the working tube to the reference line. The unit's horn
should sound as the water in the working tube touches the reference line.
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Photo 5: Listen for horn
Mark level lines anywhere in the room by placing the working tube
against the side of a stud to be marked, loosening the working tube clip,
and slowly raising or lowering the tube until the horn sounds. Draw a
light mark on the stud, recheck the spot by sound and make a permanent mark.
The simple principle behind a water
level is that the water columns inside
two open ends of a single tube will
be level with each other. Using
crude water levels (like a section of
garden hose) requires two people.
For solo work, we recommend you
buy an electronic water level (Photo 4). It's highly
accurate, has a 25-ft. working radius
and allows you to work alone and
around corners because it “honks”
when the water in the working tube
is level with the reference line back
at the unit. If you first establish a
reference mark at the level and pencil
many layout lines around a room
(including around corners, Photo
5), you can connect the marks with
chalk lines. Measure up (or down)
from any line to accurately set
acoustical ceiling track, install level
wainscoting or add lumber wall
blocking for hanging cabinets.
When filling the tube with water,
add red, water-based food coloring
for easier viewing. Clamp off both
tube ends with the clips provided so
that water doesn't suddenly spill out.
For best results, avoid water leaks
from the water level by clipping the
end of the working tube when not
actually using it for a measurement.
Take care not to step on the tube as
you move around a room.
If water does leak out or air bubbles
enter the tubing, you'll have to
refill the tube and recalibrate the
unit to maintain accuracy.
Laser levels: Best for establishing heights at long distances (50 - 100 ft.)
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Photo 6: Self-leveling laser level
Rent a rotating-head laser unit (with a self-leveling base) for long-distance
work (50 to 100 ft.) outdoors or indoors. A basic kit should
contain tools similar to those shown. Have the rental center check the
unit's calibration and battery charge as well as instruct you on its operation.
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Photo 7: Find the laser line with the detector
To level the tops of all concrete form boards, set a rotary laser on
its tripod in the middle of a building site, turn it on and wait a few
minutes while the unit self-levels. Attach the laser detector (or target)
to the elevation rod (it must always face the laser unit) and establish a reference
height. Then rest the rod on top of each board and slowly raise the form
board up and down until the laser target detects the laser beam and chirps.
We recommend that you use a
rotary laser level (Photo 6) for
tasks like setting concrete form
boards, cutting fence post tops or
building retaining walls. Like a
lighthouse, the rotary laser shoots a
level beam in a continuous circle.
Rotary laser levels
are the fastest tools for accurately
establishing leveling marks (in
direct view of the laser) anywhere
on a building site. For big time savings,
rent a rotary laser that is self-leveling.
Rotary lasers work in tandem
with a “target” laser detector. The
laser's continuous beam is too faint
to be seen in daylight, so a sensor in
the laser detector will chirp when it
detects the beam. Mounted on an
elevation rod (the kind surveyors
use), the laser detector slides up and
down the rod until it “finds” the
laser beam to establish the proper
For the fastest results setting footing
form boards, have one person
use the elevation rod to find the
laser beam and a second person set
the form boards (Photo 7). Prepare
a form board for placement by lifting
it against a support stake and
driving a couple of 3-in. deck
screws through the board, ready to
set into the stake. Once the laser
detector chirps to signal “level,”
drive the screws home.
Don't stare directly at
the laser light beam.