Werner AA1510 Instructions D'installation page 17

Section 1.4 (Continued)
Cutting the Ceiling Joists
STEP 4. Next, determine where the joist(s) should
be cut. Figure 10 shows where to mark the
joist(s) that span your chosen location. Note
that the joist(s) should be marked back
from the edge of your location a distance of
2 times the joist thickness (usually three
inches). This leaves room for two joist-sized
headers to be placed against each end of
the cut joist(s) (See Figure 16 on page 18).
Note: In some homes, especially older
ones, the joists may be slightly thicker than
the lumber you can currently buy. If your
joists have a different thickness than the
lumber you will be using for the headers,
you will need to mark the joists back from
the edge of your location a distance of two
times the header thickness instead of the
joist thickness.
STEP 5. Saw through the joist(s) being careful not to
cut through the ceiling and making sure the
cut ends of the joist(s) are flat and vertical.
Section 1.5
Framing the Rough Opening
Before Proceeding: You should have a space between the joists at least 18". Any cut joists must be attached to uncut
joists.
Goal: To create a four-sided frame the size of the rough opening using joist-sized lumber. This frame will be made of
single or double thickness headers and stringers depending upon the particular installation. The frame is necessary to
support the attic ladder and to reinforce the roof and ceiling structure.
DO NOT Do not stand or sit on the ceiling or insulation covering the ceiling — the ceiling is not made to support your
weight. You can fall through the ceiling even though it looks solid! Only the joists can support weight. To avoid falling
through the ceiling, you may want to make a working platform by laying boards across the joist. Watch out for sharp
nails sticking through the roof.
FOR YOUR SAFETY, WATCH OUT FOR OVERHEAD HAZARDS.
Dotted
Line Indicates
Your Chosen
Location
Figure 10
!
WARNING:
Cut
Here
Section of Joist
to be Removed
Cut
Here
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