How do you install architectural shingles?
Short answer. After the deck, drip edge and underlayment are down, install starter strip along the eaves and rakes, then lay courses from the bottom up, staggering the joints, keeping the exposure the manufacturer prints on the wrapper, and nailing every shingle in the marked nailing zone. Valleys, walls and penetrations get flashing as you go, and ridge caps finish the peak.
The installation sequence
- Lay out the roof. Snap horizontal chalk lines for the courses and a vertical line or two to keep offsets consistent. Architectural shingles hide small wanders, but a crooked course shows from the street.
- Install starter strip. Set it along the eaves and up the rakes with a small overhang past the drip edge, commonly about 1/4 to 3/4 inch, so the first course has a sealant line beneath it.
- First course. Lay full shingles flush with the starter edge.
- Following courses. Keep the printed exposure and offset the joints by at least the manufacturer's minimum so seams never line up.
- Nailing. Laminated shingles have a narrow zone where the two layers overlap. Nails must land there to grip both layers, flush and straight, not overdriven. Four nails per shingle is standard; very steep slopes need more.
- Valleys. Laminated shingles are usually installed with closed-cut valleys or open metal valleys rather than woven ones, over a valley leak barrier.
- Walls and chimneys. Step flashing goes in with each course, tucked under the siding or counterflashing.
- Ridge and hips. Finish with matching hip and ridge caps.
Mistakes that cost roof life
- High nails above the common bond, the leading cause of blow-offs.
- Nail guns set too hard, cutting through the shingle.
- Bundles from a single pallet laid in patches, which can show shade differences. Pull from several bundles at once.
- Skipped starter strip at the rakes.
For background, read architectural vs 3-tab shingles, roof flashing explained and synthetic underlayment vs felt.