Installation manual
www.desatech.com
118531-01C16
5.  Place ashing over pipe section(s) extend-
ing through roof. Secure base of ashing 
to roof and framing with roong nails. Be 
sure roong material overlaps top edge of 
ashing as shown in Figure 19, page 15. 
There  must  be  a  1"  clearance  from  the 
vent pipe to combustible materials.
6. 
Continue to add pipe sections until height of 
vent cap meets the minimum building code 
requirements described in Figure 9 on page 9. 
Note: You must increase vent height for steep 
roof pitches. Nearby trees, adjoining rooines, 
steep pitched roofs and other similar factors 
may cause poor draft or down-drafting in high 
winds. Increasing vent height may solve this 
problem.
7.  Twist-lock  vent  cap  onto  last  section  of 
vent pipe.
Note: If vent pipe passes through any occupied 
areas above the rst oor, including storage 
spaces and closets, you must enclose pipe. 
You may frame and sheetrock the enclosure 
with standard construction material. Make sure 
and meet the minimum allowable clearances 
to combustibles. Do not ll any of required air 
spaces with insulation.
1.  Plumb and locate knockout area for vent 
pipe.
2.  Cut and frame ceiling joist to dimensions 
shown in Figure 11, page 11.
3.  Determine where restop plate should be 
attached to thimble by test-tting thimble 
into framing. Thimble should be at or above 
height of insulation. 
VENTING INSTALLATION
Continued
Figure 22 - Vertical Venting 
Conguration using Three 90° Elbows
(Vertical Round High Wind Termination)
Horizontal (H
Horizontal (H
2
8' Min. 5' Max
10' Min. 8' Max
12' Min. 11' Max
14' Min. 14' Max
16' Min. 17' Max
18' Min. 20' Max
40' Min. 20' Max
90° Elbow
Note: Install a 
VR-58 vertical 
restrictor ring 
into inner pipe 
section prior to 
attaching vent 
termination 
cap.
Framing
Top of 
Thimble 
Should 
Measure 
to Top of 
Insullation
Hex Screw 
to Attach 
Firestop to 
Thimble
Phillips Screws 
to Attach 
Firestop to 
Framed Hole
Firestop
Figure 21 - Installing Thimble with 
Firestop
4.  Attach thimble into restop plate using 4 
hex screws provided (see Figure 21).
5.  Ret  assembly  into  opening  and  attach 
to framing with 8 Phillips screws provided 
(see Figure 20, page 15).
6.  Thimble  installation  is  ready  to  receive 
vent  pipe.  Follow  venting  installation 
instructions.
Figures  22  through  25  show  four  different 
congurations for vertical termination. 
VERTICAL VENT INSTALLATIONS USING 
MULTIPLE 90° ELBOWS










