How Much Overhang On Roofing Felt

Where a roll ends and a new one is begun the two rolls should be overlapped by four inches.

How much overhang on roofing felt.

Corrugated metal roofing generally comes in sheets that are 3x6 feet in size 18 square feet. The overhang to the next strip should be 3 8 inch. Measure the length of the roof and the breadth of one side. Points to the first course of 15 roofing felt on this roof.

Multiply those numbers and then double the result for the square footage of your roof. Just below we illustrate shingles installed with too much overhang into the gutter. Here phil explains how much overhang a roof should have at the gutter. Adjacent pieces of drip edge should overlap at least 2 inches 51 mm.

Make sure you have enough roof felt you don t want to have to stop mid way through the project to buy more felt. Greater overhang becomes a point of leverage for gusts of wind to rip off your roofing. Roofing felt is required to overlap 2 inches over the lower felt course. This should give you a 1 inch overhang on the eaves including the top edge of the installed drip edge trim installed in step 1.

A typical metal roof overhang may be 2 to 4 inches or even less. The paper should then be nailed in or stapled every three to four inches across. The drip edge should extend at least 2 inches on the roof. About 1 inch just enough to assure the water goes into the gutter and not behind it.

The vertical leg of the drip edge should be at least 1 5 inches wide and extend at least 0 25 inches below the sheathing. Video of the day. The overlapping felt creates a secondary barrier for moisture and wicks water away from the shingles above and the sheathing below. Since you will have overlap between rows this works out to a total coverage area of 400 square feet the dimensions of a 20 x 20 roof.

Some slight overhang is recommended in conjunction with a drip edge flashing to prevent water from getting under the roofing and onto underlying wood. Before you start to install corrugated metal roofing you need to figure out how much you need. The lower edge of the felt is overlapped 3 4 on top of and over the upper edge of the lower course of ice and water shield. Nail the bottom edges in place and then nail along the sides.

Therefore a 2 inch overlap provides redundancy at the edges where the barrier is weakest.