Through my experience as a contractor, I’ve come to believe in a systematic approach as the most beneficial way to install shingles. It keeps things efficient while achieving quality and consistency.
Get the Right Tools (and Keep Them Close)
There is a lot of scribing and cutting to do when installing a shingle-weaved outside or inside corner, so keeping your tools nearby saves a lot of trips to a stationary work area. I like to have a small, light circular saw, my staple gun with stainless steel staples, a caulk gun, a brad gun, and a coarse rasp. Keep shingles within reach too; being organized is key.
Work Smart with Corners
For inside corners, I like to start at the corner itself and work the row outward from there. This saves time, because I can use whatever random-sized shingle I want to start with. It’s important to note that working toward the inside corner means the last shingle in the row will likely need a precision size width cut as well as a scribe cut to match the angle of the opposing shingle. For outside corners, it’s easier to work toward them, as the last shingle on that outside edge can be held in place for corner scribing. Better yet, this shingle can be any size because it gets cut off. Working toward the outside corner also saves you from double cutting.
Snapping Lines and Corner Weaving
By having lines snapped on the wall, you’re providing a continual point of reference for measurement. I recommend using a ledger board to set the shingles across a wall, because snapped lines will soon be covered by the tops of the shingles below. Even if a line is covered up right where I’m working, I can still see it two or three feet away. Then I can use a variety of methods to extend the line on the row of shingles, like using a straightedge to mark it. You can also use measuring tape from two or three lines above to make hash marks.
When weaving outside corners, sometimes it's faster to stand in one spot and weave all at once. This helpful technique does create a challenge though: There is no way to use a ledger to keep the rows straight, which places much more reliance on your sight.
Scribing, Cutting, and Installing (Outside Corners)
This process begins at the starter course of the first row, and uses the same technique all the way up the corner. Keep in mind that each corner end cut should alternate from row to row. Simply line up the butt of the shingle to the row line, and scribe the angle line of the opposing shingle at the outside corner. Now turn the shingle over, and make your cut using a small, light circular saw, starting from the butt and cutting the line all the way up. Put the shingle back on the wall. The cut will now match the angle of the opposing shingle. Before securing the two shingles together, I like to apply a bead of latex, cedar tan caulking for extra protection. I also like to use a brad nail gun or short narrow crown staples to secure the shingle's edge to edge so that the caulk emerges.
Clean the caulk and go to the next row. The last thing to do here is to use the coarse rasp to rough up the smooth saw-cut edge so that it matches the roughness of the shingle faces. It’s a visually pleasing step.
Scribing, Cutting, and Installing (Inside Corners)
This is largely the same technique as the outside corner, with a couple of noteworthy exceptions. When working from an inside corner, use a spacer block to scribe the shingle. After setting the butt of the shingle on the line, there will be an increasing space moving toward the top of the shingle that is wider than the thickness of a carpenter pencil. I like to tape a small block to a pencil which spans the space enough to mark the line on the shingle. Once cut, it should match the profile angle of the opposing shingle. Prior to installing, I like to back-caulk as well. Bear in mind that an inside corner should also alternate on each row as you work your way up.
Install Row Filler Shingles
The final step is an easy matter, which works to fill in the rows and finish out the wall. The surest and simplest way to complete the installation is to do an entire row of shingles before moving up to the next row. The installation becomes more clear as you progress toward the corner weave, and is less prone to mistakes.
Thinking proactively about the shingle-weaving process and executing your steps in a methodical way can save a lot of time over a project which covers an entire home. As always, precision, quality, and speed are the markers of a job well done.