Installing Azek’s straight-edge shingle siding is pretty straightforward.
It begins with a wall. The wall should have a suitable nailing base, such as ½ inch plywood or 7/16-inch OSB. It should also have a weather barrier, exterior trim, and horizontal flashings as specified in the building code.
Rip and install the AZEK shingle starter strip
- Begin the siding installation by ripping a 1-½ inch starter strip from the top of enough shingle panels to run the length of the wall.
- Nail the starter strips in place about ¼ inch above the base flashing. Nails should go every eight inches, no closer than one inch from each end.
- The top nine inches of the panels will be used as a starter course. Cut the tabs off of enough shingles to run the length of the wall. Save the tabs for filling in at the top of the wall and under the windows.
- The first piece of the starter course should be 16 inches long. Install the top strips upside down with the bottom flush with the starter strip. Subsequent pieces should be full-length.
- Fasten with siding nails one inch below the top edge and with finish nails one inch above the bottom edge.
Install the starter course on AZEK shingles
Now, the first course of full shingles can go up—beginning with a full-length panel. The left edge is straight for butting against the previous panel. The right edge has a keyway cut into it so that when two panels are tightly butted, the keyway is automatically formed.
- Nail ½-inch above each keyway with a coil siding nailer or hand-driven siding nails. When using a coil nailer, make sure the nails are driven flush—not overdriven into the shingles.
- To align the next course of shingles, snap a chalk line 7 inches above the top of that first course. Use this line to align the top of the next course, and repeat for each course as you work up the wall.
- Stagger each course by 16 inches. Begin the second course with a 32-inch piece and the third course with a 16-inch piece.
- Follow the caulk manufacturer’s instructions for the proper gap between siding and trim.
Extend siding layout through windows and doors
At the windows, don’t just fill in randomly up the sides; continue the 16-inch staggered layout, extending panels through the window from one side to the other.
- Measure from the left of the panel to the window, and cut the panel. But don’t lose track of the panel layout. Extend through to where the window trim stops, and make that cut. This will keep the staggered layout consistent, providing a random appearance, so the shingles will look authentic.
- Do the same for the next course. Again, measuring to the window trim and extending the panel layout through the window. Save the offcut shingle tabs for use later.
- Work your way up the wall keeping the staggered layout so that no keyways overlap each other.
- Install another starter strip above the window, extending the length of the wall. The starter strip should be a quarter-inch above the head flashing.
- Depending on the exposure, you may need to also fill in just above the starter stip to even out the base so you can finish the top with tabs cut from the starter course. Use these tabs under the window, too.
- Fasten the tabs with finish nails in each corner.
- With the wall covered, pin the bottom corners of the shingle tabs with a 15- or 16-gauge finish nail, driven flush, again, NOT overdriven.
For prefinished AZEK shingles, use adhesive caulk
For siding that is pre-finished, you can pin the corners with Fill and Flex adhesive caulk, with dollops about an inch from the edges, and two inches above the bottom. Wide tabs get two dollops; narrow tabs get one.
Nail the panels along the top and press the adhesive into the wall. And that’s pretty much all there is to cover a standard wall with Azek’s Straight Edge shingles.
