Estimating architectural shingles
Laminated, dimensional, 30-year: the shingle on most houses. The estimate is squares to buy, starter, cap, underlayment, flashings, accessories and labor, and the squares to buy come from the courses, not from the area.
The takeoff: courses laid on every facet with the shingle's exposure, stagger and minimum piece; whole and cut pieces counted into squares and bundles; starter by the eave foot, hip and ridge cap by the true foot; underlayment by the square with lap waste; drip edge, valley metal, step and headwall flashing by the foot; boots and vents by the count; labor per square.
Courses, not area
A shingle product carries four numbers: width across, exposure, stagger and the shortest piece worth keeping. The drafter lays a course every exposure up each facet, offsets each course by the stagger, and ends every course at the facet's rakes, hips and valleys. Pieces shorter than the minimum are scrap. Add the pieces up and you have the squares to buy for that roof, with its own waste built in.
| Roof shape | What the layout catches that area × waste misses |
|---|---|
| Plain gable | Only the rake cuts. Area plus a small margin is close; the layout agrees. |
| Hip roof | Every course on every facet ends in an angled cut at both hips. Waste grows with the pitch and the number of facets. |
| Valleys and dormers | Short courses beside a dormer, cuts at both valleys, and a facet under a dormer split into pieces with a short course on each. |
| Porch at a lower pitch | Its own facet at its own pitch, with a transition flashing line between it and the main roof. |
Starter, cap and flashings
- Starter along every eave, and along the rakes if your catalog line says so, by the foot.
- Hip and ridge cap along every hip and ridge at its true length on the slope, in pieces or bundles by the coverage you set.
- Drip edge on eaves and rakes, valley metal or woven valleys by the valley foot, step flashing by the sidewall foot, headwall flashing by the headwall foot, and transition flashing at pitch breaks, all from the marked lines.
Underlayment, accessories, labor
- Underlayment. The shingle roofing type picks its field underlayment and its valley ice and water, with roll coverage, lap waste and install per square. Ice and water on the hips is a tick box.
- Accessories. Pipe boots by size, roto vents, off-ridge vents, dryer vents, goosenecks, skylights and chimney flashing, placed on the drawing and counted. Nails by the box from their uses.
- Labor. Install per square is the product's own number. Tear-off per square, trips, dump, permit, delivery, warranty, tax and markups are job settings.
What comes out
A summary with squares to buy and bundles; a materials and labor sheet; a price to the customer; an install ticket for the crew. The 3-tab page covers the same path with the 3-tab's dimensions; the squares calculator gives a quick area figure before the roof is drawn.
Questions
How many bundles of architectural shingles do I need?
Most architectural shingles cover a square with three bundles, so bundles equal squares to buy times three. The squares to buy are the laid courses on every facet, cut pieces counted, plus the starter and the hip and ridge cap, not the roof area plus a percentage.
How much waste do architectural shingles have?
It depends on the roof. A gable wastes little beyond the rake cuts; a hip roof or one with valleys and dormers wastes the angled offcuts on every course. All Roof Pricer lays each course on each facet with the stagger and the minimum piece length, so the waste is what the roof actually cuts, not a guess at 10 or 15 percent.
What dimensions does the layout use?
The shingle width, its exposure, the stagger between courses and the shortest piece worth keeping. A shingle product in the catalog carries those four numbers. The 3-tab that ships in the catalog is 12 inches wide with a 6-inch exposure, a 3-inch stagger and an 8-inch minimum; add your architectural shingle with its own numbers.
Are starter, hip and ridge cap counted?
Yes. Starter runs the eaves by the foot; hip and ridge cap runs the hips and ridges by the foot at their true length on the slope. Both are lines in the catalog with their coverage per piece or bundle.
Is labor different for architectural shingles than 3-tab?
Each product carries its own install labor per square, so the two can differ or match as you price them. Tear-off per square and the other job costs are the same settings.