Werner AA1510 Instrucciones De Instalación página 20

Section 1.5 (Continued)
Framing the Rough Opening
Installing Stringers
STEP 1. Measure the stringer length "S" between
the headers (See Figure 17).
STEP 2. Cut a stringer to this length. Use
joist-sized lumber.
STEP 3. If the ceiling joist does not provide one side
of the frame, then cut a second stringer the
same length as the first one. Note that only
one stringer is needed in Figure 17 because
the ceiling joist provides one side of
the frame.
STEP 4. Position the stringer(s) along the unframed
side(s) of your location (See Figure 18).
Check that the inside dimensions of the
frame are at least 18" x 24".
STEP 5. To attach the stringer(s) to the headers, use
nails that are long enough to go through
both headers and into the stringer at least
one inch. In most cases, a 4" nail (20d)
will be long enough. Square the stringer(s)
to the headers at one end and drive 3 nails
through the headers and into the stringer.
Check for squareness, then nail the other
end. Check the rough opening for
squareness by measuring across the
diagonals. The two measurements must
be within 1/8" to be considered square
(See Figure 18).
Note: A 3/4" wood floor 27" min. deep by the full width of
your opening is required for the attachment of the assist
arm. Please refer to Step 5 on page 6 of this manual for
instructions on attaching assist arm.
19
Headers
Figure 17
Diagonal
Measurements
Support floor for power
assist arm min. 27" by
full width of opening
Figure 18
Headers
S
Stringer
Nails
27"
Full Width
of opening