Ceiling Chimney Hole/

Vermont Castings EWF36A

Ceiling Chimney Hole/

Possible Obstructions

The size of the hole in ceiling will vary with the angle at which the chimney passes through ceiling.

Drive a nail up through ceiling at marked chimney center point. Go to floor above and see where hole will be cut. Check to see where existing ceiling joists and other possible obstructions are located...i.e. wiring, plumbing etc... If necessary, re-position chimney and/or fireplace to avoid obstructions.

Cutting the Hole

Cover fireplace collar opening and cut proper sized chimney hole in chimney.

Framing the Ceiling Hole

Frame the ceiling chimney hole as shown in Figure

10.It is good practice to use framing lumber that is the same size as the ceiling joists; this is a requirement at attic level.

The following table gives firestop spacer model num- bers:

Chimney Hole Size

 

Angle of Chimney at Ceiling

Size of Chimney

Vertical

30°

 

FS2A

FS6A

8” Flue

17¹⁄” x 17¹⁄

17⁷⁄” x 29⁵⁄

 

(445 x 445mm)

(454 x 753mm)

Fig. 9 Ceiling chimney hole sizes necessary for installing firestop spacer.

The inside dimension of the frame must be the same as the hole size selected from Figure 9 in order to provide required the 2” (51mm) air space between the outside diameter of the chimney and the edges of the framed ceiling hole.

Positioning, Safety Strips,

Securing the Fireplace

Slide fireplace into position.

Safety strips are used to ensure that any combustible materials in front of the fireplace are protected even though a noncombustible hearth extension is required.

When the finished extended hearth is added, the top of the finished hearth must be flush with the bottom of the fireplace. “Z” shaped metal safety strips have been supplied with the fireplace and are required for instal- lation. The safety strips provided have a 1” offset. For applications with a greater offset, “Z” shaped strips will have to be fabricated of metal. Overlap safety strips at least 1/2” to provide a positive joint. The safety strips must also extend at least 1¹⁄” (38mm) beyond the sides of the fireplace. (Fig. 11)

Existing

17¹⁄

17¹⁄

 

Ceiling

 

(445mm)

 

 

(445mm)

 

Joists

 

 

 

 

 

 

 

 

 

 

 

Chimney

 

 

 

 

Hole

New Framing

 

 

 

Members

 

 

 

 

 

 

Ceiling

FP551b

 

 

 

 

Fig. 10

Typical frame for ceiling chimney hole.

 

 

 

 

“Z” Metal Safety

 

 

 

Strips (1 or 2 pcs.)

 

 

 

 

“Z” Safety

 

 

 

 

Strip

 

 

 

Fire-

Decorative

1¹⁄

 

place

Hearth

 

 

Face

(38mm)

1/2” Min.

Plat-

 

 

 

Overlap

 

 

 

form

 

 

 

 

 

 

 

 

Hearth Ext.

FP557b

Fig. 11

Safety strip installation.

 

 

Note: Safety strips are not required over noncombus- tible floors where all supports at the base of the fire- place are noncombustible.

Two (2) nailing flanges are supplied with the fireplace. To level the box and secure it firmly in place, remove the nailing flanges from the hearth and install at the sides of the fireplace as shown in Figure 12.

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MHP EWF36A manual Ceiling Chimney Hole Possible Obstructions, Cutting the Hole, Framing the Ceiling Hole, Chimney Hole Size