More homes in the U.S. are clad with vinyl siding than any other material. Vinyl is simple to install and begins with the installation of the trim pieces called "accessories." There are dozens of different accessories that can be used to trim a house but for many projects there are four or five basic pieces: Starter strip, J- channel, outside corner post, inside corner post and utility trim (also called undersill trim or finish trim). Expect to spend one third to one half of your time on a project installing the accessories. It can be awkward to install vinyl accessories straight because they are hollow and floppy. I use several techniques to align the trim straight and fasten it properly. This ensures a professional looking job and speeds the installation of the siding panels. Remember to cover the house with building paper or housewrap before you install the siding to shed water that gets behind the vinyl siding and trim.
Installing Channel Pieces
Install J-channel around windows and doors. Install the bottom piece at the opening first, then the sides and finally the top. Rather than measuring each length with a tape measure, hold a piece of J-channel in place with one end flush to an edge and mark the opposite edge. This saves time and reduces errors.
Bottom Channel. Cut the bottom piece flush with the outside edges of the opening. Metal shears work great to cut channel. Drive a nail tight to the wall through a slot in the center of the J-channel. Drive additional nails into the center of slots every 12 to 16 inches. If the wall sheathing is foam or hardboard you must be sure your nails hit studs. Take precautions where nails have no backing, like at inside and outside corners.
Side Channel. Mark the side J-channels to reach from the top of the opening to the front edge (or non-nail flange side) of the bottom J-channel. Cut the center web of the channel 3/4 inch at the bottom so it forms a tab and bend it outward. Interlock the tab into the bottom J-channel. [photos] Drive a nail in the top of the J-channel at the top of a slot to hold it in place. Drive additional nails in the center of the slots every 12 to 16 inches.
Top Channel. Cut the top J-channel to reach the outside edges of the side channels. Cut 3/4 inch tabs [photo] at each end to interlock with the side J channels. Nail this piece the same as the bottom piece.
Installing Corner Posts
Inside and outside corner posts look better when they are perfectly straight. Snap chalk lines to guide installation.
- Center a scrap piece of corner post over a corner by measuring from the corner to the outside edges of the post flanges.
- Mark the top and bottom of all inside and outside corners. Snap lines on both sides of the corners for precise alignment with the flanges.
- Hang each post from a pair of nails at the top. Drive a nail tight into the top of a slot on each side of the post. Drive additional nails 12 to 16 inches apart into the center of slots.
- Join pieces of corner post by making small notches into the corners of the top of the lower piece. Slide the lower piece into the upper piece for an overlapping joint.
Starter Strip
Starter strip may be made from aluminum or vinyl. Starter strip designs differ between vinyl siding manufactures. Use starter strips from the same company that makes your siding.
-Install starter strip along the bottom edge of the walls. The starter strip interlocks with the first course of siding panels and holds their bottom edges in place.
-Snap a level chalk line between inside and outside corner posts all the way around the building and set the top of the starter strip along that line. It's important to install all the starter strips at the same height along the bottom so the siding profiles match at corners.
-Leave pieces of starter strip about 1/2 inch short of the corner post flanges. Drive nails into the center of slots 12 to 16 inches apart.
Hanging Vinyl
Vinyl expands when it's hot and contracts when it's cold. Driving fasteners too tight often causes the material to buckle or wrinkle. The heads of nails must be left a little loose to permit the vinyl to slide behind them. And the nails must be driven into the center of the nailing slots to allow them to move. This is why installing vinyl siding is called "hanging vinyl" rather than "nailing vinyl". Vinyl siding actually "hangs" from the nails rather than being held in by the nail heads.
The only nails you drive tight are those in a center slot of horizontal trim pieces (like the J-channel pieces under and over windows) and in the top slot of vertical trim (like corner posts). These tight fasteners keep the trim in place.
You can hang vinyl with galvanized roofing nails. Some pneumatic roofing nailers have nose attachments for aligning nails with the nailing slots. Narrow crown staples also work: Nose adapters on staplers orient one leg of the staple into the slot and the other above. Staplers and nailers can speed production considerably.
