Lennox RAVELLE 30 Installation And Operation Instructions Manual page 14

Facing Installation Considerations
Non-combustible cement board (such as Wonderboard, Durock, or Har-
dybacker) must extend 10" (254 mm) above the 1" (25mm) top reveal
and a minimum of 5" (127 mm) from each side reveal (see drawing
below - right) . This cement board may be 1/4" (6 .3 mm) thick or greater,
but would normally be the thickness of the drywall - for example 1/2" (13
mm) . The cement board may be fastened with drywall screws .
10" (254mm)
Minimum
Cement Board
5" (127mm)
Minimum
Figure 9
14
Sheetrock
(25mm)
1" Reveal
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
The screws should be driven through the cement board into the outer
metal skin of the fireplace . The sheetrock (drywall) is then butted up
to the cement board . The sheetrock above the fireplace should also be
fastened to the fireplace by driving screws into the outer metal skin of
the fireplace .
Facing Less Than 1" Thick: If the combined thickness of the facing
material (eg . 3/8" [9 .5 mm] thick ceramic tile and 1/2" (13 mm) thick
cement board) is less than 1" (25 mm), then the tile can be placed behind
the fireplace (see below) .
3/8" (9.5 mm) Tile and 1/2" (12.7 mm) Cement
Cement Board - minimum
of 5" (127 mm) wide
Board Behind Fireplace Face
Sheetrock