On either side of the ridge board.
How to cut a roof for a ridge vent.
To vent the ridge cut back sheathing at least 1 in.
Take some chalk and run it down the center.
Cut a 1 5 8 opening along the ridge on each side figure b.
Snap parallel lines on either side of the peak.
Then use a pencil to trace the outside edge of the framing square s tongue.
Use a utility knife with a hook blade to cut the shingles back 3 inches or as recommended by the vent manufacturer from the ridge.
Using a circular saw with a carbide tip blade one of the roofers plunges the saw into the ridge at the ends and then follows the chalk line.
In this case just cut away the building paper to expose the underside of the plastic ridge vent mesh plastic cor a vent material looks like a plastic version of the edge of a cardboard box or the opening into the aluminum ridge vent depending on which.
Then run underlayment and wood shingles to the edge of the sheathing before nailing a ridge vent over the opening.
The product instructions should specify how big to cut the slots based on your roof s support system.
Maximum slot opening is 3 1 4 wide.
There is a process to install ridge vents and it begins with removing cap shingles along your roof s ridgeline.
The roofer said he could take those off and install ridge caps but he d have to cut along either side of the peak by about 4 and although it would look better cosmetically having shingles covering the peak it would not produce as good ventilation as the ridge vent now sitting on top of the house and it would expose me to problems.
Cut a 7 8 opening along the ridge on each side figure a.
Cut along both chalk lines with the saw and remove the center piece.
Roofs without a ridge board.
If installing on an existing roof remove the cap shingles from the ridge.
Roofs with a ridge board.
Choose which end of your rafter you want to be the top.
To begin the ridge vent installation they measure down 3 inches from the top of the ridge and snap a line to cut the opening for the ridge vent.
If you re cutting through a typical roof with 5 8 inch decking set the cutting depth of the blade to 3 4 inches.
The plumb or ridge cut is made at the top of the rafter.
The ridge vent on a wood shingled roof can be finished in one of two ways.
It s less common for us to find that a builder cut away plywood for the ridge vent but that s he installed building paper or more likely roofing felt over the opening before installing the ridge vent.