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How to Measure Vinyl Siding


Before ordering accessories, you also have to determine the width of the J-Channel into which you will fit the vinyl siding. To do this, you must first determine which of two methods you will use to apply sheathings or underlayments. This is covered in more detail under “Sheathings.”

NOTE: Refer to product catalog for product accessory recommendations and availability.

Starter strip: Measure along base of building.

J-Channel: For siding installations, measure around doors and windows, under eaves, at rake edges of gables where dormer meets roofline, and anywhere else required to provide a finished appearance.

For soffit, measure along wall under eave and along fascia board.

For porch ceilings, measure along perimeter of the porch area.

F-Channel: For soffit, measure along wall under eve.

For porch ceilings, measure along perimeter of the porch area.

3-1/2" and 5" Lineals: For casing, measure along perimeter of doors and windows. For gables, measure at rake edges of gables where dormer meets roof line.

Undersill trim: Measure above and below windows and above doors and top course of siding below soffit.

Soffit H-bar: Measure diagonals at all eave corners.

Outside cornerpost: Measure length of outside corners.

Inside cornerpost: Measure length of inside corners.

NOTE: If you plan to use J-Channel instead of inside a corner post, remember to double this measurement and add the total to your entry for J-Channel.

How to install horizontal siding

Dual undersill trim: Measure along top of wall where siding will meet eaves.

Read More: Installing accessories


How To Cut Vinyl Siding

To cut panels to size, follow these procedures:

Cross cuts

For a precise cut, use a power circular saw equipped with a sharp, fine-tooth plywood blade.

For best results, reverse blade direction. Cut one or two panels at a time, carefully advancing the saw through the vinyl. A rule of thumb: The lower the temperature, the slower the feed rate. Panels can also be cut with snips. Use a square to mark the cut line. Start the cut at the top lock and continue to the bottom of the panel.

Rip cuts

Use a utility knife to score the panel along the cut line. Bend the panel back and forth along the score line until it snaps apart cleanly. Use a combination of tin snips and utility knife to cut panels to fit around windows and doors.

How to install vertical siding