Installation Instructions
CertainTeed Vinyl Siding Installation Guide
91
Triple 3-1/3 Solid, InvisiVent 
and Perimeter Soffit
Installation over open eaves
In most situations, T3-1/3 Solid, InvisiVent and Perimeter Soffit 
should be installed like our standard soffit products. However, 
when it is installed over open eaves, follow these installation 
techniques.
Install receiving channels
There are two ways to install receiving channels for soffit. The best 
approach is to select a method that works most effectively with 
the construction techniques used to create the eave. Examine 
the illustrations, and find the one that most closely resembles the 
construction methods on your particular project.
Use either 3/4" J-channel or 3/4" F-channel, or make receiving 
channels using coil stock. Install the receiving channels following 
the details shown in the illustrations.
Nail the channels every 12" to 16", positioning the nail in the center 
of the slot. Do not nail tightly.
NOTE: If you are concerned about excessive insect infiltration 
with InvisiVent or Perimeter Soffit, cover the opening with 
corrosion-resistant mesh or other screening before installing 
the soffit.
Install soffit
Nail the soffit every 16" or 24", depending upon local building 
codes and stud spacing. T3-1/3 soffit will span up to 24" without 
additional nailing strips.
Installation over existing soffit
When installing InvisiVent or Perimeter Soffit over an existing 
solid wood soffit, you must cut openings into the existing soffit to 
provide adequate airflow through the soffit. The goal is to have 
at least 9 square inches of net free air per lineal foot of soffit. 
Removing a center portion of the existing soffit will provide the 
desired airflow.
Using a saw, cut along the length of the existing soffit. Leave 2" 
to 3" from both the wall and the fascia so that you will have 
enough wood surface to securely fasten the soffit.
Remove the center portion of the existing soffit. 
Install the soffit as described above.
NOTE: Leaving solid areas of existing soffit intact reduces 
ventilation and must be considered when calculating 
total ventilation.
fascia cap or 
coil stock
open 
rafter
F-channel
soffit
add framing
soffit
J-channel










