Werner AA1510 Instructions D'installation page 19

Section 1.5 (Continued)
Framing the Rough Opening
Double Headers
STEP 1. Measure the header length "H" between
the uncut joists (See Figure14).
STEP 2. Cut 4 headers this length. Use joist-sized
lumber.
STEP 3. Place one of these headers against the end
of the cut joist(s) (See Figure 15). It must
fit snugly between the uncut joists.
Hammer it into position if necessary; if it is
more than 1/16" too long, trim it. If it
is more than 1/16" too short, cut
another piece.
STEP 4. Square the header to the uncut joist and
nail the header to the end of the cut
joist(s) with 3 nails (See Figure 15).
STEP 5. Check header for squareness then drive
3 nails through each joist into each
end of the header (See Figure 15).
STEP 6. Place a second header against the first
header and nail it to the first header with
3 nails between each joist (See Figure 16).
STEP 7. Drive 3 nails through the joists into each
end of the second header (See Figure 16).
STEP 8. Repeat steps 3-7 to install headers at the
opposite end of the opening.
STEP 9. To frame the other side(s) of the rough
opening, go to "Installing Stringers" on page 19.
Figure 14
Nails
Uncut Joists
Figure 15
Nails
Figure 16
H
Cut Joist
First Header
Second Header
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