Roof Replacement Materials List: Shingles, Underlayment and Vents
A simple gable roof on a 30 × 40 ft house at a 6/12 pitch is 15.0 roofing squares, which takes 50 bundles of shingles (with 10% waste), 2 rolls of synthetic underlayment, about 15 pieces of drip edge and roughly 4,800 nails. This is the materials list for a full replacement. Many people hire the job out, and knowing the quantities makes quotes much easier to compare.
The materials list
| What to buy | How much | How we worked it out |
|---|---|---|
| Architectural shingles | 50 bundles (16.5 squares) | Roofing calculator: footprint with 12 in overhangs, multiplied by the 6/12 slope factor of 1.118, plus 10% waste, at three bundles a square |
| Synthetic underlayment | 2 rolls of 1,000 ft² | Covers the whole roof deck with about 10% for laps. The roof is 1,503 ft² |
| Drip edge | 15 pieces of 10 ft | About 80 ft along the eaves and 67 ft up the rakes |
| Starter shingles | About 147 ft | Along the eaves and rakes, bought as starter strips or cut from shingles |
| Hip and ridge caps | Check the coverage per bundle | The ridge is about 40 ft on a simple gable. Bundles of ridge cap cover a set number of linear feet: it is printed on the pack |
| Roofing nails | About 4,800 | Roughly 320 per square. Many bundles list the nailing pattern, and the maker's pattern wins |
| Ice and water shield | Eaves and valleys | A self-adhesive membrane along the eaves and in valleys, where the instructions or your climate call for it |
| Flashing and pipe boots | Count the penetrations | Replace the flashing around chimneys, walls and vent pipes, and the rubber boots on plumbing vents |
| Roof vents | 16 ft of ridge vent and 8 soffit vents | Attic ventilation calculator: for a 1,200 ft² attic at the 1:300 ratio |
Other costs to plan for: tear-off and disposal of the old roof, repairs to any rotted decking, and the permit.
Materials for other house sizes
Simple gable roof, 6/12 pitch, 12 in overhangs, 10% waste:
| House footprint | Squares | Bundles | Underlayment rolls | Drip edge (10 ft) |
|---|---|---|---|---|
| 24 × 24 ft | 7.6 | 25 | 1 | 11 |
| 28 × 40 ft | 14.1 | 47 | 2 | 15 |
| 30 × 40 ft | 15.0 | 50 | 2 | 15 |
| 32 × 48 ft | 19.0 | 63 | 3 | 18 |
| 36 × 50 ft | 22.1 | 73 | 3 | 19 |
A steeper roof is bigger: the multiplier is 1.118 at 6/12 and 1.302 at 10/12. Use the roofing calculator for your pitch, and the roofing squares guide for the complete method.
Safety and planning
- Roofing is dangerous. Falls are the main risk: use a harness, anchored properly, and do not work on a wet, icy or steep roof without the right equipment.
- Shingle bundles weigh about 60 to 80 lb each. Spread them across the rafters, never in one pile.
- Check your local rules on permits, the number of layers allowed, and the shingles you may use.
- Plan the work for a dry spell, with the old roof torn off and the new one underlaid within the same day.
- Make sure the attic is ventilated and insulated: it affects how long the new shingles last. See the attic ventilation guide.
Estimates only. Quantities on a real roof depend on its valleys, hips, dormers and chimneys: measure each plane, or have a roofer check your numbers.
Frequently asked questions
How many bundles of shingles for a 30x40 house?
50 bundles for a simple gable roof at a 6/12 pitch with 12 inch overhangs and 10% waste (three bundles per square). A steeper roof or a complicated one needs more.
How many roofing squares is a 30x40 house?
About 15.0 squares at a 6/12 pitch, or 16.5 squares with 10% waste. One square is 100 ft² of roof.
How many rolls of underlayment do I need?
2 rolls of 1,000 ft² synthetic underlayment for this roof, which is 1,503 ft² and includes about 10% for laps.
How much roof ventilation does a 1,200 sq ft attic need?
At the 1:300 ratio, 576 in² of net free vent area, split between low and high: about 16 ft of ridge vent and 8 soffit vents of 40 in².
More guides
Tools & materials for this project
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Estimates only. Quantities depend on your materials, site and supplier. Confirm important numbers before you order, and follow local building codes for anything structural.