How many shingles for a 18-square roof?
A 18-square roof is 1,800 square feet of roof surface — the kind of roof you'd find on a compact single-story or ranch home. Here is the bundle count by shingle type, the realistic count once waste is added, and the rest of the material list.
Bundles by shingle type
| Shingle type | Bundles per square | Before waste | With waste (10–25%) |
|---|---|---|---|
| 3-tab | 3 | 54 | 60–68 |
| Architectural | 4 | 72 | 80–90 |
The waste range matters: a simple gable roof sits near the low end (10%), while a complex hip roof with valleys and dormers pushes toward the high end (25%). Order for your roof's complexity, not just the bare square count.
What kind of roof is 18 squares?
This is a common size for smaller ranch and bungalow roofs at a moderate 4/12 to 6/12 pitch. Remember that roof size is not the same as house floor area — because of pitch and overhangs, the roof surface is usually larger than the footprint. A 18-square roof might sit on a house with a noticeably smaller floor plan.
The rest of the material list
Shingles are only part of the order. For a roof of about this size you would also expect, very roughly:
| Material | Approximate quantity |
|---|---|
| Starter strip | ~2 bundle(s) |
| Hip & ridge cap | ~3 bundle(s) |
| Underlayment (synthetic) | ~2 roll(s) |
| Drip edge | eave + rake length ÷ 10 ft |
How to confirm your roof is 18 squares
Measure each roof plane's footprint, multiply by the pitch multiplier to get true area, add waste, and divide by 100. A 1,800 sq ft roof is exactly 18 squares. If you only know your house footprint, the roof will be larger once pitch is applied — see how to measure a roof and what is a roofing square.
Common questions
Is 18 squares the same as 1,800 square feet?
Yes — one roofing square is 100 square feet, so 18 squares is exactly 1,800 sq ft of roof surface.
How many bundles is that?
72 bundles of architectural shingles or 54 bundles of 3-tab, before adding waste.
Should I round up?
Always. Partial bundles aren't sold, and a little spare makes future repairs match. Round up after adding waste.