Left and Right Half Triangle Vents are measured the same as the Triangle.
Just as a half of the vent.
Specifying "left" means the upright center height is on the right.
With the base point pointing to the left.
This is a Left Half Triangle Louver Vent.
And specify "right" for the upright height to be on the left and the base pointing to the right.
Making a Right Half Triangle Louver Vent.
These are common to be against or beside a chimney.
The base measure inside the framing is the width.
The height is the upright side to the top point.
These equal the vent "opening size".
For this the vent will be manufactured 1/4" smaller per side to install into this opening.
Do not measure the top angle. It has no value.
For "tip to tip" measuring, it is the same concept.
Exclude any flange on the vent and only measure across the bottom of the vent.
And again, the sides are the height.
"Tip to tip" means the vent will be the measures ordered.
For the vent depth, the measure will depend upon the space available behind the wall.
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