How To Install J Trim Around Windows

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Siding & Exterior Trim

How-To

Installing J-Channel for Vinyl Siding around Windows

Follow these guidelines for cut and installing J-aqueduct around windows before fitting the vinyl siding panels.

J-channel around windows

I of the terminal steps before installing vinyl siding panels is trimming around all sides of windows and doors with J-channel (aka "J"). This channel hides the cutting edges of the siding where it meets windows and doors, making for a clean look. The J pieces will lap each other to drain water, so add together twice the width of the forepart of the J to each length. That's unremarkably ii in.

Cutting the J to length with a miter saw or snips. At both ends of the top and bottom pieces, cutting forth the within of the channel the width of the forepart of the J to create a flap. one Make similar cuts to the side pieces but cut out the flaps. Nail the J in place, starting with the bottom, using covering nails every foot. 2 Fold the lesser-piece flaps up along the side of the window, then nail the side pieces in place, lapping the bottom flaps. Then install the elevation piece of J. That goes over whatever baste cap that's in identify, and its flaps should lap into the side J-channel.

Cut the side J-channel — 1) Cut the side channels to leave flaps that constrict between the upper and lower J-aqueduct and the window.

2) Showtime the J-channel installation around windows by nailing the bottom section in place with roofing nails.

Detailing the Meridian Piece of J-channel

The upper piece of vinyl always has to exist cut at the soffit. A lot of carpenters snap information technology into the piece below, and constrict the height into the J above, and call information technology proficient. I've seen a lot of pieces of siding installed that way laying on the basis after a windstorm.

Some other approach is to tack the top in place with painted aluminum nails. That works, but the vinyl can buckle in the oestrus. I use a snap-lock dial to cut small slots in the vinyl nearly its top edge and use these slots for the aluminum nails driven at an bending to get past the face of the J-aqueduct.

Small slots punched in the cut edge — Small slots punched in the cutting edge allow nailing in more visible locations (under windows or soffits) with modest aluminum nails.

Hold the siding in place under the window to mark the width of the window. iii Then measure from the buttlock on the course below to the height of the J (inside the aqueduct recess) and deduct ane⁄4 in. for expansion. This is the depth of the cut you'll make in the siding panel. 4 Extend the get-go marks to this depth and connect them using a straightedge. Using snips, make the cut on your marks. 5

mark the width of a cut to clear the J-channel — 3) With the J in place, hold the siding in its installed location to marker the width of the slice you'll have to cut out for the window.

Measure from the buttlock to the J-channel. — 4) Measure from the buttlock of the lower class to the recess of the J-channel. This is the depth of the cutting for the window.

5) When all your measurements are marked, apply snips to cut the panel at the marks.

Using Undersill

An alternative to J-channel for below windows and soffits is undersill.

Undersill is meant to grip and concur the top of vinyl siding whose nail flange has been cut off. It's a good production when it can exist used, specially under longer windows, where siding tucked into J would go without nails for a distance. But it won't keep the siding in if the siding is cutting near the betoken where it thickens at the eye or the bottom.

Using Undersill