Installation Instructions

FIGURE 2

The process for mulling or stacking differs from

mulling and

stacking, please follow the proper

steps.

Please observe the following definition for terms

used in the subsequent instructions:

• Stacked: Joining two or more units together

vertically (FIGURE 1).

1. Place units to be stacked on a clean flat surface

(interior facing down) in the position that they will

be assembled (FIGURE 1).

IMPORTANT: When placing units to

be mulled or stacked, make sure the sills or

water weeps on the units will be facing towards

the sill (bottom) of the rough opening when

they are installed (FIGURE 1).

2. Nailing fins must be removed from jambs that

will be attached together. Remove the bottom

transom fin and top door fin (FIGURE 2).

3. Use a utility knife to score each fin, tight to the

frame, the entire length of the fin (FIGURE 2).

4. Use a hacksaw or tin snips to make an initial cut

into a fin (FIGURE 3A). Now bend the fin, adjacent

to this cut, up and down with locking pliers until it

breaks off (FIGURE 3). Use this method to remove

the door’s top nailing fin and transom’s bottom fin.

FIGURE 1

FIGURE 3

Stacking, mulling, or combinations of stacking and

mulling installation restrictions along with additional

reinforcements may apply for your area.

the door manufacturer recommends that the

installer consult a registered Architect or local

Structural Engineer for guidance to insure the

installation meets all specific codes, conditions or

applications regarding to stacking, mulling, or

stacking and mulling combinations.

Field Stacking – Adding Transom – 2 Wide Only

Transoms or stacked units cannot be

added to 4-Wide patio doors as shown here.

Any transom or stacking, on a 4-Wide door,

must be done by providing framing to create

separate support for the transom or stacked

unit.