How to Miter SmartVent on a Transitional Roof

When installing SmartVent on a transitional roof you should use the following steps to achieve the best results for both curb appeal and ventilation.

 How to miter SmatrVent step 2
Step 1
Cut 45° angle with razor knife starting from the tapered edge working towards the Fabric exterior.  


Step 2

Cut angle.


Discard the cutoff piece


Step 3

Discard cut off piece.

Step 4

From another piece of SmartVent

Cut 45° angle with razor knife starting from the opposite side tapered edge working towards the Fabric exterior.

Step 5

Install tight & cut flush with lift edge (continues in step 6 )


Step 6

Using a square & razor knife.


Step 7

Place end cap to the SmartVent™ & place fabric 1/2 below.

Step 8

Nail SmartVent™ end cap in place with fabric 1/2 showing.

Step 9

Take the fabric and wrap it over the vent & nail it tight. Install ice & water membrane & shingles. 


Step 10

Finished Installation.

Ensure shingle overhangs 1/2” past the lift edge


SmartVent is a tapered, under shingle plastic product designed for installation along the soffit edge of the roof or the facing edge of dormer rakes and goes virtually unnoticed. It allows air to flow freely through the 1″ roof decking slit providing more than adequate soffit ventilation to maximize ridge vent effectiveness. This is extremely important since most ridge vent products require an equal amount of ventilation at the soffit in order to work properly. SmartVent, when used at both soffits, has a total NFA rating of 18 sq. in. per foot (or 9 sq. in. per foot on each side of a standard gable roof).

Click here for SmartVent Specifications

Most houses with ridge vents do not have the proper soffit ventilation required because attic insulation blocks the soffit vents. SmartVent allows cooler air to enter under the shingle, through the 1″ roof slit and out the ridge vent providing superior air flow and attic cooling.

Click here for an expanding list of SmartVent Dealers. If no dealer is located near you please give us a call at 1-800-622-4455 and we will be happy to locate a dealer for you.


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