Installation manual
www.desatech.com
118531-01C 15
VENTING INSTALLATION
Continued
INSTALLATION FOR VERTICAL 
TERMINATION
Note: Vertical restrictor must be  installed in 
all vertical installations.
1.  Determine the route your vertical venting 
will  take.  If  ceiling joists,  roof  rafters or 
other  framing  will  obstruct  the  venting 
system, consider an offset (see Figure 19) 
to avoid cutting load bearing members.
  Note: Pay special attention to these instal-
lation instructions for required clearances 
(air space) to combustibles when passing 
through ceilings, walls, roofs, enclosures, 
attic rafters, etc. Do not pack air spaces 
with insulation. Also note maximum verti-
cal  rise  of  the venting  system  and  any 
maximum horizontal offset limitations. 
2.  Set replace in desired location. Drop a 
plumb line down from ceiling to position 
of  replace  exit  ue.  Mark  center  point 
where vent will  penetrate ceiling. Drill  a 
small locating hole at this point.
  Drop a plumb line from inside of roof to 
locating hole in ceiling. Mark center point 
where vent will penetrate roof. Drill a small 
locating hole at this point.
Figure 19 - 45° and 30° Offset with Wall 
Strap
Roof 
Flashing
Wall 
Strap
45° 
Elbows
WS-58 
Wall Strap
2 - 2 x 4 
Vertical 
Header
OSR58-30 
30° Offset 
Return
Horizontal 
Frame Member
1.  Cut a 10 
3
/
4
" square hole in the ceiling using 
locating hole as a center point. Opening 
should be framed to 10 
3
/
4
" x 10 
3
/
4
" inside 
dimensions, as shown in Figure 11 on page 
11,  using  framing  lumber  the  same  size 
as the ceiling joists. If area above ceiling 
is an  insulated  ceiling or an attic  space, 
you must use restop thimble and special 
restop included with the kit from top side 
to prevent insulation from contacting vent 
pipe (see Thimble Installation, page 16). If 
area above ceiling is a living space, install 
restop below framed hole. Firestop should 
be installed with no less than three nails per 
side (see Figure 20).
2.  Assemble  desired  lengths  of  pipe  and 
elbows necessary to reach from replace 
ue up through restop. Be sure all pipe 
and  elbow  connections  are  fully  twist-
locked (see Figure 10, page 11).
3.  Cut a hole in the roof using locating hole as 
a center point. (Cover any exposed open 
vent pipes before cutting hole in roof.) The 
10 
3
/
4
"  x  10 
3
/
4
"  hole  must be  measured 
on  the  horizontal. Actual length  may  be 
larger depending on  pitch of  roof. There 
must be a 1" clearance from vent pipe to 
combustible materials. Frame opening as 
shown in Figure 11, page 11.
4.  Connect a section of pipe and extend up 
through the hole.
  Note:  If  an  offset  is  needed  to  avoid 
obstructions, you must support vent pipe 
every 3 feet. Use wall straps for this pur-
pose (see Figure 19). Whenever possible, 
use 45° elbows instead of 90° elbows. The 
45° elbow offers less restriction to the ow 
of ue gases and intake air.
Figure 20 - Installing Firestop
If area above is an attic or insulated area, 
install restop above framed hole.
If area above is an insulated area is a living 
space, install restop below framed hole.










